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Pyne S, Pyne P, Kumar Mitra R. The inner hydration in surfactant/cholesterol vesicles differs from the outer one: a spectroscopic investigation. Chemphyschem 2022; 23:e202200337. [PMID: 35775165 DOI: 10.1002/cphc.202200337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 06/21/2022] [Indexed: 11/07/2022]
Abstract
Vesicles contain two aqueous regions: inner core and outer-to-bulk . It has remained an open question whether hydration behaviour in the inner core differs from the outer-to-bulk region, mostly owning to the inability of the conventional spectroscopic techniques to deconvolute the contribution from these two regions. We, using THz-FTIR spectroscopy (1.5-13.5 THz) experimentally probe the inner hydration of three differently charged surfactant/cholesterol vesicles composed of SDS, CTAB and Brij 30. Both dynamic light scattering (DLS) and atomic force microscopy (AFM) measurements affirm the transition from micelles to vesicles as cholesterol is added into surfactant solutions. FTIR measurements show that hydration behaviour changes significantly as micelles are converted into vesicles, the change been exclusively caused due to the formation of an inner core . Our measurements on the hydrogen bond stretch and librational motion of the inner hydration show distinct features compared to the overall hydration, which in turn is found to be surfactant type and cholesterol concentration dependent.
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Affiliation(s)
- Sumana Pyne
- Department of Chemical Biological and Macromolecular Sciences, S N Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700106, India
| | - Partha Pyne
- Department of Chemical Biological and Macromolecular Sciences, S N Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700106, India
| | - Rajib Kumar Mitra
- Department of Chemical Biological and Macromolecular Sciences, S N Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700106, India
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52
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M Boymelgreen A, Kunti G, Garcia-Sanchez P, Ramos A, Yossifon G, Miloh T. The role of particle-electrode wall interactions in mobility of active Janus particles driven by electric fields. J Colloid Interface Sci 2022; 616:465-475. [PMID: 35421638 DOI: 10.1016/j.jcis.2022.02.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 01/19/2022] [Accepted: 02/04/2022] [Indexed: 11/29/2022]
Abstract
HYPOTHESIS The interaction of active particles with walls can explain discrepancies between experiments and theory derived for particles in the bulk. For an electric field driven metallodielectric Janus particle (JP) adjacent to an electrode, interaction between the asymmetric particle and the partially screened electrode yields a net electrostatic force - termed self-dielectrophoresis (sDEP) - that competes with induced-charge electrophoresis (ICEP) to reverse particle direction. EXPERIMENTS The potential contribution of hydrodynamic flow to the reversal is evaluated by visualizing flow around a translating particle via micro-particle image velocimetry and chemically suppressing ICEP with poly(l-lysine)-g-poly(ethylene glycol) (PLL-PEG). Mobility of Polystyrene-Gold JPs is measured in KCl electrolytes of varying concentration and with a capacitive SiO2 coating at the metallic JP surface or electrode. Results are compared with theory and numerical simulations accounting for electrode screening. FINDINGS PLL-PEG predominantly suppresses low-frequency mobility where propulsive electro-hydrodynamic jetting is observed; supporting the hypothesis of an electrostatic driving force at high frequencies. Simulations and theory show the magnitude, direction and frequency dispersion of JP mobility are obtained by superposition of ICEP and sDEP using the JP height and capacitance as fitting parameters. Wall proximity enhances ICEP and sDEP and manifests a secondary ICEP charge relaxation time dominating in the contact limit.
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Affiliation(s)
- A M Boymelgreen
- Department of Mechanical and Materials Engineering, Florida International University, Miami, FL, 33174, USA.
| | - G Kunti
- Department of Mechanical Engineering, Technion - Israel Institute of Technology, Technion City, Haifa, 3200003, Israel
| | - P Garcia-Sanchez
- Departamento de Electrónica y Electromagnetismo, Facultad de Física, Universidad de Sevilla, Avenida Reina Mercedes s/n, Sevilla 41012, Spain
| | - A Ramos
- Departamento de Electrónica y Electromagnetismo, Facultad de Física, Universidad de Sevilla, Avenida Reina Mercedes s/n, Sevilla 41012, Spain
| | - G Yossifon
- Department of Mechanical Engineering, Technion - Israel Institute of Technology, Technion City, Haifa, 3200003, Israel
| | - T Miloh
- Department of Mechanical Engineering, Tel Aviv University, Ramat Aviv 6997801, Israel
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53
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Wang R, Zhu X, Zhu L, Li H, Xue J, Yu S, Liu X, Gan S, Xue Q. Multifunctional superwetting positively charged foams for continuous oil/water emulsion separation and removal of hazardous pollutants from water. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2022.120683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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54
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Tang L, Li X, Feng H, Ma C, Chang Q, Zhang J. Infiltration of salt solutions through illite particles: Effect of nanochannel size and cation type. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2022.128581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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55
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Zhang Y, Guo S, Yu ZG, Qu H, Sun W, Yang J, Suresh L, Zhang X, Koh JJ, Tan SC. An Asymmetric Hygroscopic Structure for Moisture-Driven Hygro-Ionic Electricity Generation and Storage. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2201228. [PMID: 35338530 DOI: 10.1002/adma.202201228] [Citation(s) in RCA: 38] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 03/23/2022] [Indexed: 06/14/2023]
Abstract
The interactions between moisture and materials give rise to the possibility of moisture-driven energy generation (MEG). Current MEG materials and devices only establish this interaction during water sorption in specific configurations, and conversion is eventually ceased by saturated water uptake. This paper reports an asymmetric hygroscopic structure (AHS) that simultaneously achieves energy harvesting and storage from moisture absorption. The AHS is constructed by the asymmetric deposition of a hygroscopic ionic hydrogel over a layer of functionalized carbon. Water absorbed from the air creates wet-dry asymmetry across the AHS and hence an in-plane electric field. The asymmetry can be perpetually maintained even after saturated water absorption. The absorbed water triggers the spontaneous development of an electrical double layer (EDL) over the carbon surface, which is termed a hygro-ionic process, accounting for the capacitive properties of the AHS. A peak power density of 70 µW cm-3 was realized after geometry optimization. The AHS shows the ability to be recharged either by itself owing to a self-regeneration effect or via external electrical means, which allows it to serve as an energy storage device. In addition to insights into moisture-material interaction, AHSs further shows potential for electronics powering in assembled devices.
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Affiliation(s)
- Yaoxin Zhang
- Department of Materials Science and Engineering, National University of Singapore, 9 Engineering drive 1, Singapore, 117575, Singapore
| | - Shuai Guo
- Department of Materials Science and Engineering, National University of Singapore, 9 Engineering drive 1, Singapore, 117575, Singapore
| | - Zhi Gen Yu
- Institute of High Performance Computing, Agency for Science, Technology and Research, 1 Fusionopolis Way, Singapore, 138632, Singapore
| | - Hao Qu
- Department of Materials Science and Engineering, National University of Singapore, 9 Engineering drive 1, Singapore, 117575, Singapore
| | - Wanxin Sun
- Division of Nano Surfaces, Bruker Corporation, 11 Biopolis Way, Singapore, 138667, Singapore
| | - Jiachen Yang
- Department of Materials Science and Engineering, National University of Singapore, 9 Engineering drive 1, Singapore, 117575, Singapore
| | - Lakshmi Suresh
- Department of Materials Science and Engineering, National University of Singapore, 9 Engineering drive 1, Singapore, 117575, Singapore
| | - Xueping Zhang
- Department of Materials Science and Engineering, National University of Singapore, 9 Engineering drive 1, Singapore, 117575, Singapore
| | - J Justin Koh
- Department of Materials Science and Engineering, National University of Singapore, 9 Engineering drive 1, Singapore, 117575, Singapore
| | - Swee Ching Tan
- Department of Materials Science and Engineering, National University of Singapore, 9 Engineering drive 1, Singapore, 117575, Singapore
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56
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Relevance of Colloid Inherent Salt Estimated by Surface Complexation Modeling of Surface Charge Densities for Different Silica Colloids. COLLOIDS AND INTERFACES 2022. [DOI: 10.3390/colloids6020023] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Potentiometric titrations have been routinely used to measure the proton-related surface charge density (SCD) of particles in solution. Here, we quantify the SCD of silica nanoparticles (NPs) that are commercially available as charge-stabilized colloids (by the addition of NaOH) in the presence of known amounts of added NaCl. The experimental results are simulated by surface complexation models (SCMs) of the electrical double layer (EDL). The modeling results suggest that involving only the added NaCl electrolyte yields poor agreement between the experiment and the best achievable fit. An increase in the Na concentration accounting for the colloid inherent salt (CIS) associated with these charge-stabilized colloids results in much better simulations. In the available literature, this CIS has often been disregarded. However, in the modeling, the total concentration of Na must be known for a consistent mole balance and derivation of reliable ion-pair binding constants. If the CIS is not accounted for or the original suspensions are not dialyzed, the presence of CIS renders the study of those colloids difficult, particularly when investigating specific ion effects, since the CIS always interferes. In the present work, we show that the SCM-estimated amount of CIS from varying the total salt and solid concentration agrees surprisingly well with the manufacturer specification.
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57
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Yang C, Wu X, Xia H, Zhou J, Wu Y, Yang R, Zhou G, Qiu L. 3D Printed Template-Assisted Assembly of Additive-Free Ti 3C 2T x MXene Microlattices with Customized Structures toward High Areal Capacitance. ACS NANO 2022; 16:2699-2710. [PMID: 35084815 DOI: 10.1021/acsnano.1c09622] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Ti3C2Tx MXene is a promising material for electrodes in microsupercapacitors. Recent efforts have been made to fabricate MXene electrodes with designed structures using 3D printing to promote electrolyte permeation and ion diffusion. However, challenges remain in structural design diversity due to the strict ink rheology requirement and limited structure choices caused by existing extrusion-based 3D printing. Herein, additive-free 3D architected MXene aerogels are fabricated via a 3D printed template-assisted method that combines 3D printed hollow template and cation-induced gelation process. This method allows the use of MXene ink with a wide range of concentrations (5 to 150 mg mL-1) to produce MXene aerogels with high structural freedom, fine feature size (>50 μm), and controllable density (3 to 140 mg cm-3). Through structure optimization, the 3D MXene aerogel shows high areal capacitance of 7.5 F cm-2 at 0.5 mA cm-2 with a high mass loading of 54.1 mg cm-2. It also exhibits an ultrahigh areal energy density of 0.38 mWh cm-2 at a power density of 0.66 mW cm-2.
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Affiliation(s)
- Chuang Yang
- Shenzhen Geim Graphene Center, Tsinghua Berkeley Shenzhen Institute and Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Xin Wu
- Shenzhen Geim Graphene Center, Tsinghua Berkeley Shenzhen Institute and Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
- Foshan (Southern China) Institute for New Materials, Dali Town, Nanhai District, Foshan 528231, China
| | - Heyi Xia
- Shenzhen Geim Graphene Center, Tsinghua Berkeley Shenzhen Institute and Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Jingzhuo Zhou
- Shenzhen Geim Graphene Center, Tsinghua Berkeley Shenzhen Institute and Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Yifan Wu
- Shenzhen Geim Graphene Center, Tsinghua Berkeley Shenzhen Institute and Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
- Department of Chemistry, The University of Hong Kong, Hong Kong 999077, China
| | - Rui Yang
- Shenzhen Geim Graphene Center, Tsinghua Berkeley Shenzhen Institute and Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Guangmin Zhou
- Shenzhen Geim Graphene Center, Tsinghua Berkeley Shenzhen Institute and Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Ling Qiu
- Shenzhen Geim Graphene Center, Tsinghua Berkeley Shenzhen Institute and Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
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58
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Fujimura Y, Kawakatsu T, Nakagawa K, Shintani T, Yoshioka T. Mechanism of silica nanoparticles removal in an isopropyl alcohol/water solution with an anion exchange membrane. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2021.118366] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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59
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Panda PK, Singh D, Köhler MH, de Vargas DD, Wang ZL, Ahuja R. Contact electrification through interfacial charge transfer: a mechanistic viewpoint on solid-liquid interfaces. NANOSCALE ADVANCES 2022; 4:884-893. [PMID: 36131814 PMCID: PMC9417913 DOI: 10.1039/d1na00467k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 12/13/2021] [Indexed: 06/15/2023]
Abstract
Contact electrification (triboelectrification) has been a long-standing phenomenon for 2600 years. The scientific understanding of contact electrification (triboelectrification) remains un-unified as the term itself implies complex phenomena involving mechanical contact/sliding of two materials involving many physico-chemical processes. Recent experimental evidence suggests that electron transfer occurs in contact electrification between solids and liquids besides the traditional belief of ion adsorption. Here, we have illustrated the Density Functional Theory (DFT) formalism based on a first-principles theory coupled with temperature-dependent ab initio molecular dynamics to describe the phenomenon of interfacial charge transfer. The model captures charge transfer dynamics upon adsorption of different ions and molecules on AlN (001), GaN (001), and Si (001) surfaces, which reveals the influence of interfacial charge transfer and can predict charge transfer differences between materials. We have depicted the substantial difference in charge transfer between fluids and solids when different ions (ions that contribute to physiological pH variations in aqueous solutions, e.g., HCl for acidic pH, and NaOH for alkaline pH) are adsorbed on the surfaces. Moreover, a clear picture has been provided based on the electron localization function as conclusive evidence of contact electrification, which may shed light on solid-liquid interfaces.
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Affiliation(s)
- Pritam Kumar Panda
- Condensed Matter Theory Group, Materials Theory Division, Department of Physics and Astronomy, Uppsala University Box 516 SE-75120 Uppsala Sweden
| | - Deobrat Singh
- Condensed Matter Theory Group, Materials Theory Division, Department of Physics and Astronomy, Uppsala University Box 516 SE-75120 Uppsala Sweden
| | - Mateus H Köhler
- Departamento de Física, Universidade Federal de Santa Maria Santa Maria 97105-900 Brazil
| | - Douglas D de Vargas
- Departamento de Física, Universidade Federal de Santa Maria Santa Maria 97105-900 Brazil
| | - Zhong Lin Wang
- School of Materials Science and Engineering, Georgia Institute of Technology Atlanta GA 30332 USA
- Beijing Institute of Nanoenergy and Nanosystems, CAS Beijing 100083 China
| | - Rajeev Ahuja
- Condensed Matter Theory Group, Materials Theory Division, Department of Physics and Astronomy, Uppsala University Box 516 SE-75120 Uppsala Sweden
- Department of Physics, Indian Institute of Technology (IIT) Ropar Rupnagar 140001 Punjab India
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60
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Caetano DLZ, Metzler R, Cherstvy AG, de Carvalho SJ. Adsorption of lysozyme into a charged confining pore. Phys Chem Chem Phys 2021; 23:27195-27206. [PMID: 34821240 DOI: 10.1039/d1cp03185f] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Several applications arise from the confinement of proteins on surfaces because their stability and biological activity are enhanced. It is also known that the way in which a protein adsorbs on the surface is important for its biological function since its active sites should not be obstructed. In this study, the adsorption properties of hen egg-white lysozyme, HEWL, into a negatively charged silica pore is examined by employing a coarse-grained model and constant-pH Monte Carlo simulations. The role of electrostatic interactions is taken into account via including the Debye-Hückel potentials into the Cα structure-based model. We evaluate the effects of pH, salt concentration, and pore radius on the protein preferential orientation and spatial distribution of its residues regarding the pore surface. By mapping the residues that stay closer to the pore surface, we find that the increase of pH leads to orientational changes of the adsorbed protein when the solution pH gets closer to the HEWL isoelectric point. Under these conditions, the pKa shift of these important residues caused by the adsorption into the charged confining surface results in a HEWL charge distribution that stabilizes the adsorption in the observed protein orientation. We compare our observations to the results of the pKa shift for HEWL available in the literature and to some experimental data.
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Affiliation(s)
- Daniel L Z Caetano
- Institute of Chemistry, State University of Campinas (UNICAMP), Campinas, Brazil.,Center for Computational Engineering and Sciences, State University of Campinas (UNICAMP), Campinas, Brazil
| | - Ralf Metzler
- Institute for Physics & Astronomy, University of Potsdam, 14476 Potsdam-Golm, Germany
| | - Andrey G Cherstvy
- Institute for Physics & Astronomy, University of Potsdam, 14476 Potsdam-Golm, Germany.,Institut für Physik, Humboldt-Universität zu Berlin, 12489 Berlin, Germany
| | - Sidney J de Carvalho
- Department of Physics, São Paulo State University (UNESP), Institute of Biosciences, Humanities and Exact Sciences, São José do Rio Preto, Brazil.
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61
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Ma Y, Wang D. Revealing Electrical Double-Layer Potential of Substrates by Hysteresis Ion Transport in Scanning Ion Conductance Microscopy. Anal Chem 2021; 93:15821-15825. [PMID: 34816713 DOI: 10.1021/acs.analchem.1c04486] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The electrical double layer (EDL) at solid-liquid interfaces is key to interfacial transport and reaction processes and numerous emerging applications exploiting such processes. Herein, by studying hysteresis ion-transport processes in nanopipettes near charged substrates, we found the resulting cross-point potential (Vcp) to represent the surface potential of both nanopipettes and substrates. After the subtraction of Vcp in bulk solution, the remaining ΔVcp shows excellent exponential decay with respect to the separation distance from the substrates and agrees very well with the classical double-layer theory. The revealed new hysteresis ion transport in nanopipettes would provide a new way for the simple and direct EDL imaging of various interfaces of interest with nanoscale resolution in scanning ion conductance microscopy.
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Affiliation(s)
- Yingfei Ma
- Department of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 10049, P. R. China
| | - Dengchao Wang
- Department of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 10049, P. R. China
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62
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Wang T, Hsu CA, Lee YJ, Wang CF, Chen CW, Dong CD. Impact of microporous structures of esterified cellulose filter papers on Co (II) rejection in cross-flow microfiltration. Sep Purif Technol 2021. [DOI: 10.1016/j.seppur.2021.119738] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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63
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Predictive surface complexation model of the calcite-aqueous solution interface: The impact of high concentration and complex composition of brines. J Colloid Interface Sci 2021; 609:852-867. [PMID: 34839916 DOI: 10.1016/j.jcis.2021.11.084] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 10/29/2021] [Accepted: 11/16/2021] [Indexed: 11/23/2022]
Abstract
Electrochemical interactions at calcite-water interface are characterized by the zeta potential and play an important role in many subsurface applications. In this work we report a new physically meaningful surface complexation model that is proven to be efficient in predicting calcite-water zeta potentials for a wide range of experimental conditions. Our model uses a two-stage optimization for matching experimental observations. First, equilibrium constants are optimized, and the Stern layer capacitance is optimized in the second stage. The model is applied to a variety of experimental sets that correspond to intact natural limestones saturated with equilibrated solutions of low-to-high salinity, and crushed Iceland Spar sample saturated with NaCl at non-equilibrium conditions. The proposed linear correlation of the Stern layer capacitance with the ionic strength is the main novel contribution to our surface complexation model without which high salinity experiments cannot be modelled. Our model is fully predictive given accurately known conditions. Therefore, the reported parameters and modelling protocol are of significant importance for improving our understanding of the complex calcite-water interfacial interactions. The findings provide a robust tool to predict electrochemical properties of calcite-water interfaces, which are essential for many subsurface applications including hydrology, geothermal resources, CO2 sequestration and hydrocarbon recovery.
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64
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Ma E, Geiger FM. Divalent Ion Specific Outcomes on Stern Layer Structure and Total Surface Potential at the Silica:Water Interface. J Phys Chem A 2021; 125:10079-10088. [PMID: 34761927 DOI: 10.1021/acs.jpca.1c08143] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The second-order nonlinear susceptibility, χ(2), in the Stern layer and the total interfacial potential drop, Φ(0)tot, across the oxide:water interface are estimated from SHG amplitude and phase measurements for divalent cations (Mg2+, Ca2+, Sr2+, and Ba2+) at the silica:water interface at pH 5.8 and various ionic strengths. We find that interfacial structure and total potential depend strongly on ion valency. We observe statistically significant differences between the experimentally determined χ(2) value for NaCl and that of the alkali earth series but smaller differences between ions of the same valency in that series. These differences are particularly pronounced at intermediate salt concentrations, which we attribute to the influence of hydration structure in the Stern layer. Furthermore, we corroborate the differences by examining the effects of anion substitution (SO42- for Cl-). Finally, we identify that hysteresis in measuring the reversibility of ion adsorption and desorption at fused silica in forward and reverse titrations manifests itself both in Stern layer structure and in total interfacial potential for some of the salts, most notably for CaCl2 and MgSO4 but less so for BaCl2 and NaCl.
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Affiliation(s)
- Emily Ma
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60660, United States
| | - Franz M Geiger
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60660, United States
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65
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Bischoff M, Biriukov D, Předota M, Marchioro A. Second Harmonic Scattering Reveals Ion-Specific Effects at the SiO 2 and TiO 2 Nanoparticle/Aqueous Interface. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2021; 125:25261-25274. [PMID: 35591899 PMCID: PMC9109693 DOI: 10.1021/acs.jpcc.1c07191] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 10/12/2021] [Indexed: 06/01/2023]
Abstract
Ion-specific effects play a crucial role in controlling the stability of colloidal systems and regulating interfacial processes. Although mechanistic pictures have been developed to explain the electrostatic structure of solid/water colloidal interfaces, ion-specific effects remain poorly understood. Here we quantify the average interfacial water orientation and the electrostatic surface potential around 100 nm SiO2 and TiO2 colloidal particles in the presence of NaCl, RbCl, and CaCl2 using polarimetric angle-resolved second harmonic scattering. We show that these two parameters can be used to establish the ion adsorption mechanism in a low ionic strength regime (<1 mM added salt). The relative differences between salts as a function of the ionic strength demonstrate cation- and surface-specific preferences for inner- vs outer-sphere adsorption. Compared to monovalent Rb+ and Na+, Ca2+ is found to be preferentially adsorbed as outer-sphere on SiO2 surfaces, while a dominant inner-sphere adsorption is observed for Ca2+ on TiO2. Molecular dynamics simulations performed on crystalline SiO2 and TiO2 surfaces support the experimental conclusions. This work contributes to the understanding of the electrostatic environment around colloidal nanoparticles on a molecular level by providing insight into ion-specific effects with micromolar sensitivity.
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Affiliation(s)
- Marie Bischoff
- Laboratory
for fundamental BioPhotonics (LBP), Institute of Bioengineering (IBI),
and Institute of Materials Science (IMX), School of Engineering (STI), École Polytechnique Fédérale
de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Denys Biriukov
- Institute
of Organic Chemistry and Biochemistry, Czech
Academy of Sciences, Flemingovo nám. 2, 16610 Prague 6, Czech Republic
- Department
of Physics, Faculty of Science, University
of South Bohemia, Branišovská 1760, 370
05 České Budějovice, Czech Republic
| | - Milan Předota
- Department
of Physics, Faculty of Science, University
of South Bohemia, Branišovská 1760, 370
05 České Budějovice, Czech Republic
| | - Arianna Marchioro
- Laboratory
for fundamental BioPhotonics (LBP), Institute of Bioengineering (IBI),
and Institute of Materials Science (IMX), School of Engineering (STI), École Polytechnique Fédérale
de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
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66
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Zhou J, Saeidi N, Wick LY, Kopinke FD, Georgi A. Adsorption of polar and ionic organic compounds on activated carbon: Surface chemistry matters. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 794:148508. [PMID: 34218142 DOI: 10.1016/j.scitotenv.2021.148508] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 06/01/2021] [Accepted: 06/13/2021] [Indexed: 06/13/2023]
Abstract
Persistent and mobile organic compounds (PMOCs) are often detected micropollutants in the water cycle, thereby challenging the conventional wastewater and drinking water treatment techniques. Carbon-based adsorbents are often less effective or even unable to remove this class of pollutants. Understanding of PMOC adsorption mechanisms is urgently needed for advanced treatment of PMOC-contaminated water. Here, we investigated the effect of surface modifications of activated carbon felts (ACFs) on the adsorption of six selected PMOCs carrying polar or ionic groups. Among three ACFs, defunctionalized ACF bearing net positive surface charge at neutral pH provides the most versatile sorption efficiency for all studied PMOC types representing neutral, anionic and cationic compounds. Ion exchange capacity giving quantitative information of sorbent surface charges at specified pH is recognized as a frequently underestimated key property for evaluating adsorbents aiming at PMOC adsorption. A most recently developed prediction tool for Freundlich parameters in PMOC adsorption was applied and the prediction results are compared to the experimental data. The comparison demonstrates the so far underestimated importance of the sorbent surface chemistry for PMOC adsorption affinity and capacity. PMOC adsorption mechanisms were additionally investigated by adsorption experiments at various temperatures, pH values and electrolyte concentrations. Exothermic sorption was observed for all sorbate-sorbent pairs. Adsorption is improved for ionic PMOCs on AC carrying sites of the same charge (positive or negative) at increased electrolyte concentration, while not affected for neutral PMOCs unless strong electron donor-acceptor yet weak non-Coulombic interactions exist. Our findings will allow for better design and targeted application of activated carbon-based sorbents in water treatment facilities.
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Affiliation(s)
- Jieying Zhou
- Helmholtz Centre for Environmental Research UFZ, Department of Environmental Engineering, D-04318 Leipzig, Germany
| | - Navid Saeidi
- Helmholtz Centre for Environmental Research UFZ, Department of Environmental Engineering, D-04318 Leipzig, Germany
| | - Lukas Y Wick
- Helmholtz Centre for Environmental Research UFZ, Department of Environmental Microbiology, D-04318 Leipzig, Germany
| | - Frank-Dieter Kopinke
- Helmholtz Centre for Environmental Research UFZ, Department of Environmental Engineering, D-04318 Leipzig, Germany
| | - Anett Georgi
- Helmholtz Centre for Environmental Research UFZ, Department of Environmental Engineering, D-04318 Leipzig, Germany.
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67
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Tang Z, Lin S, Wang ZL. Quantifying Contact-Electrification Induced Charge Transfer on a Liquid Droplet after Contacting with a Liquid or Solid. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2102886. [PMID: 34476851 DOI: 10.1002/adma.202102886] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 07/13/2021] [Indexed: 06/13/2023]
Abstract
Contact electrification (CE) is a common physical phenomenon, and its mechanisms for solid-solid and liquid-solid cases have been widely discussed. However, the studies about liquid-liquid CE are hindered by the lack of proper techniques. Here, a contactless method is proposed for quantifying the charges on a liquid droplet based on the combination of electric field and acoustic field. The liquid droplet is suspended in an acoustic field, and an electric field force is created on the droplet to balance the acoustic trap force. The amount of charges on the droplet is thus calculated based on the equilibrium of forces. Further, the liquid-solid and liquid-liquid CE are both studied by using the method, and the latter is focused. The behavior of negatively precharged liquid droplet in the liquid-liquid CE is found to be different from that of the positively precharged one. The results show that the silicone oil droplet prefers to receive negative charges from a negatively charged aqueous droplet rather than positive charges from a positively charged aqueous droplet, which provides a strong evidence about the dominant role played by electron transfer in the liquid-liquid CE.
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Affiliation(s)
- Zhen Tang
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing, 100083, P. R. China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Shiquan Lin
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing, 100083, P. R. China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Zhong Lin Wang
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing, 100083, P. R. China
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA, 30332-0245, USA
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68
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Shi L, McMillan JR, Yu D, Chen X, Tucker CJ, Wasserman E, Mohler C, Chen Z. Effect of Surfactant Concentration and Hydrophobicity on the Ordering of Water at a Silica Surface. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:10806-10817. [PMID: 34455791 DOI: 10.1021/acs.langmuir.1c01731] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The performance of nonionic surfactants is mediated by the interfacial interactions at the solid-liquid interface. Here we applied sum frequency generation (SFG) vibrational spectroscopy to probe the molecular structure of the silica-nonionic surfactant solution interface in situ, supplemented by quartz crystal microbalance with dissipation monitoring (QCM-D) and molecular dynamics (MD) simulations. The combined studies elucidated the effects of nonionic surfactant solution concentration, surfactant composition, and rinsing on the silica-surfactant solution interfacial structure. The nonionic surfactants studied include ethylene-oxide (EO) and butylene oxide (BO) components with different ratios. It was found that the CH groups of the surfactants at the silica-surfactant solution interfaces are disordered, but the interfacial water molecules are ordered, generating strong SFG OH signals. Solutions with higher concentrations of surfactant lead to a slightly higher amount of adsorbed surfactant at the silica interface, resulting in more water molecules being ordered at the interface, or a higher ordering of water molecules at the interface, or both. MD simulation results indicated that the nonionic surface molecules preferentially adsorb onto silanol sites on silica. A surfactant with a higher EO/BO ratio leads to more water molecules being ordered and a higher degree of ordering of water molecules at the silica-surfactant solution interface, exhibiting stronger SFG OH signal, although less material is adsorbed according to the QCM-D data. A thin layer of surfactants remained on the silica surface after multiple water rinses. To the best of our knowledge, this is the first time the combined approaches of SFG, QCM-D and MD simulation techniques have been applied to study nonionic surfactants at the silica-solution interface, which enhances our understanding on the interfacial interactions between nonionic surfactants, water and silica. The knowledge obtained from this study can be helpful to design the optimal surfactant concentration and composition for future applications.
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Affiliation(s)
- Lirong Shi
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Janet R McMillan
- Core R&D, The Dow Chemical Company, Midland, Michigan 48674, United States
| | - Decai Yu
- Core R&D, The Dow Chemical Company, Midland, Michigan 48674, United States
| | - Xiaoyun Chen
- Core R&D, The Dow Chemical Company, Midland, Michigan 48674, United States
| | | | - Eric Wasserman
- Dow Home & Personal Care, The Dow Chemical Company, Collegeville, Pennsylvania 19426, United States
| | - Carol Mohler
- Core R&D, The Dow Chemical Company, Midland, Michigan 48674, United States
| | - Zhan Chen
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
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69
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Li X, Lin X, Li Y, Liu WT. Gate Alignment of Liquid Water Molecules in Electric Double Layer. Front Chem 2021; 9:717167. [PMID: 34485244 PMCID: PMC8416066 DOI: 10.3389/fchem.2021.717167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Accepted: 08/02/2021] [Indexed: 11/13/2022] Open
Abstract
The behavior of liquid water molecules near an electrified interface is important to many disciplines of science and engineering. In this study, we applied an external gate potential to the silica/water interface via an electrolyte-insulator-semiconductor (EIS) junction to control the surface charging state. Without varying the ionic composition in water, the electrical gating allowed an efficient tuning of the interfacial charge density and field. Using the sum-frequency vibrational spectroscopy, we found a drastic enhancement of interfacial OH vibrational signals at high potential in weakly acidic water, which exceeded that from conventional bulk-silica/water interfaces even in strong basic solutions. Analysis of the spectra indicated that it was due to the alignment of liquid water molecules through the electric double layer, where the screening was weak because of the low ion density. Such a combination of strong field and weak screening demonstrates the unique tuning capability of the EIS scheme, and would allow us to investigate a wealth of phenomena at charged oxide/water interfaces.
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Affiliation(s)
- Xiaoqun Li
- Physics Department, State Key Laboratory of Surface Physics, Key Laboratory of Micro and Nano Photonic Structures [Ministry of Education (MOE)], Fudan University, Shanghai, China
| | - Xin Lin
- Physics Department, State Key Laboratory of Surface Physics, Key Laboratory of Micro and Nano Photonic Structures [Ministry of Education (MOE)], Fudan University, Shanghai, China
| | - Ying Li
- Physics Department, State Key Laboratory of Surface Physics, Key Laboratory of Micro and Nano Photonic Structures [Ministry of Education (MOE)], Fudan University, Shanghai, China
| | - Wei-Tao Liu
- Physics Department, State Key Laboratory of Surface Physics, Key Laboratory of Micro and Nano Photonic Structures [Ministry of Education (MOE)], Fudan University, Shanghai, China
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70
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Ivanova AA, Cheremisin AN, Barifcani A, Iglauer S, Phan C. Molecular dynamics study of the effect of sodium and chloride ions on water-surfactant-hydrocarbon interfaces. Chem Phys 2021. [DOI: 10.1016/j.chemphys.2021.111243] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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71
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Källquist I, Lindgren F, Lee MT, Shavorskiy A, Edström K, Rensmo H, Nyholm L, Maibach J, Hahlin M. Probing Electrochemical Potential Differences over the Solid/Liquid Interface in Li-Ion Battery Model Systems. ACS APPLIED MATERIALS & INTERFACES 2021; 13:32989-32996. [PMID: 34251812 PMCID: PMC8397238 DOI: 10.1021/acsami.1c07424] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Accepted: 06/29/2021] [Indexed: 06/13/2023]
Abstract
The electrochemical potential difference (Δμ̅) is the driving force for the transfer of a charged species from one phase to another in a redox reaction. In Li-ion batteries (LIBs), Δμ̅ values for both electrons and Li-ions play an important role in the charge-transfer kinetics at the electrode/electrolyte interfaces. Because of the lack of suitable measurement techniques, little is known about how Δμ̅ affects the redox reactions occurring at the solid/liquid interfaces during LIB operation. Herein, we outline the relations between different potentials and show how ambient pressure photoelectron spectroscopy (APPES) can be used to follow changes in Δμ̅e over the solid/liquid interfaces operando by measuring the kinetic energy (KE) shifts of the electrolyte core levels. The KE shift versus applied voltage shows a linear dependence of ∼1 eV/V during charging of the electrical double layer and during solid electrolyte interphase formation. This agrees with the expected results for an ideally polarizable interface. During lithiation, the slope changes drastically. We propose a model to explain this based on charge transfer over the solid/liquid interface.
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Affiliation(s)
- Ida Källquist
- Department
of Physics and Astronomy, Uppsala University, 751 20 Uppsala, Sweden
| | - Fredrik Lindgren
- Department
of Physics and Astronomy, Uppsala University, 751 20 Uppsala, Sweden
| | - Ming-Tao Lee
- Department
of Chemistry - Ångström, Uppsala
University, 751 20 Uppsala, Sweden
| | | | - Kristina Edström
- Department
of Chemistry - Ångström, Uppsala
University, 751 20 Uppsala, Sweden
| | - Håkan Rensmo
- Department
of Physics and Astronomy, Uppsala University, 751 20 Uppsala, Sweden
| | - Leif Nyholm
- Department
of Chemistry - Ångström, Uppsala
University, 751 20 Uppsala, Sweden
| | - Julia Maibach
- Institute
for Applied Materials (IAM), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Maria Hahlin
- Department
of Physics and Astronomy, Uppsala University, 751 20 Uppsala, Sweden
- Department
of Chemistry - Ångström, Uppsala
University, 751 20 Uppsala, Sweden
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72
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Zhang Q, Tamayo A, Leonardi F, Mas-Torrent M. Interplay between Electrolyte-Gated Organic Field-Effect Transistors and Surfactants: A Surface Aggregation Tool and Protecting Semiconducting Layer. ACS APPLIED MATERIALS & INTERFACES 2021; 13:30902-30909. [PMID: 34156234 PMCID: PMC8289230 DOI: 10.1021/acsami.1c05938] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 06/08/2021] [Indexed: 06/13/2023]
Abstract
Molecular surfactants, which are based on a water-insoluble tail and a water-soluble head, are widely employed in many areas, such as surface coatings or for drug delivery, thanks to their capability to form micelles in solution or supramolecular structures at the solid/liquid interface. Electrolyte-gated organic field-effect transistors (EGOFETs) are highly sensitive to changes occurring at their electrolyte/gate electrode and electrolyte/organic semiconductor interfaces, and hence, they have been much explored in biosensing due to their inherent amplification properties. Here, we demonstrate that the EGOFETs and surfactants can provide mutual benefits to each other. EGOFETs can be a simple and complementary tool to study the aggregation behavior of cationic and anionic surfactants at low concentrations on a polarized metal surface. In this way, we have monitored the monolayer formation of cationic and anionic surfactants at the water/electrode interface with p-type and n-type devices, respectively. On the other hand, the operational stability of EGOFETs has been dramatically enhanced, thanks to the formation of a protective layer on top of the organic semiconductor by exposing it to a high concentration of a surfactant solution (above the critical micelle concentration). Stable performances were achieved for more than 10 and 2 h of continuous operation for p-type and n-type devices, respectively. Accordingly, this work points not only that EGOFETs can be applied to a wider range of applications beyond biosensing but also that these devices can effectively improve their long-term stability by simply treating them with a suitable surfactant.
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Affiliation(s)
- Qiaoming Zhang
- School
of Physical Science and Technology, Southwest
University, 400715 Chongqing, P. R. China
- Institut
de Ciència de Materials de Barcelona, ICMAB-CSIC, Bellaterra, 08193 Barcelona, Spain
| | - Adrián Tamayo
- Institut
de Ciència de Materials de Barcelona, ICMAB-CSIC, Bellaterra, 08193 Barcelona, Spain
| | - Francesca Leonardi
- Institut
de Ciència de Materials de Barcelona, ICMAB-CSIC, Bellaterra, 08193 Barcelona, Spain
| | - Marta Mas-Torrent
- Institut
de Ciència de Materials de Barcelona, ICMAB-CSIC, Bellaterra, 08193 Barcelona, Spain
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73
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Hydrodynamic diameter and zeta potential of nanostructured lipid carriers: Emphasizing some parameters for correct measurements. Colloids Surf A Physicochem Eng Asp 2021. [DOI: 10.1016/j.colsurfa.2021.126610] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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74
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Zamora Zeledón JA, Kamat GA, Gunasooriya GTKK, Nørskov JK, Stevens MB, Jaramillo TF. Probing the Effects of Acid Electrolyte Anions on Electrocatalyst Activity and Selectivity for the Oxygen Reduction Reaction. ChemElectroChem 2021. [DOI: 10.1002/celc.202100500] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- José A. Zamora Zeledón
- Department of Chemical Engineering Stanford University 443 Via Ortega Stanford California 94305 United States
- SUNCAT Center for Interface Science and Catalysis SLAC National Accelerator Laboratory 2575 Sand Hill Road Menlo Park California 94025 United States
| | - Gaurav Ashish Kamat
- Department of Chemical Engineering Stanford University 443 Via Ortega Stanford California 94305 United States
- SUNCAT Center for Interface Science and Catalysis SLAC National Accelerator Laboratory 2575 Sand Hill Road Menlo Park California 94025 United States
| | | | - Jens K. Nørskov
- Catalysis Theory Center Department of Physics Technical University of Denmark 2800 Kongens Lyngby Denmark
| | - Michaela Burke Stevens
- Department of Chemical Engineering Stanford University 443 Via Ortega Stanford California 94305 United States
- SUNCAT Center for Interface Science and Catalysis SLAC National Accelerator Laboratory 2575 Sand Hill Road Menlo Park California 94025 United States
| | - Thomas F. Jaramillo
- Department of Chemical Engineering Stanford University 443 Via Ortega Stanford California 94305 United States
- SUNCAT Center for Interface Science and Catalysis SLAC National Accelerator Laboratory 2575 Sand Hill Road Menlo Park California 94025 United States
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75
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Ouyang L, Shaik R, Xu R, Zhang G, Zhe J. Mapping Surface Charge Distribution of Single-Cell via Charged Nanoparticle. Cells 2021; 10:cells10061519. [PMID: 34208707 PMCID: PMC8235745 DOI: 10.3390/cells10061519] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 06/12/2021] [Accepted: 06/13/2021] [Indexed: 11/16/2022] Open
Abstract
Many bio-functions of cells can be regulated by their surface charge characteristics. Mapping surface charge density in a single cell's surface is vital to advance the understanding of cell behaviors. This article demonstrates a method of cell surface charge mapping via electrostatic cell-nanoparticle (NP) interactions. Fluorescent nanoparticles (NPs) were used as the marker to investigate single cells' surface charge distribution. The nanoparticles with opposite charges were electrostatically bonded to the cell surface; a stack of fluorescence distribution on a cell's surface at a series of vertical distances was imaged and analyzed. By establishing a relationship between fluorescent light intensity and number of nanoparticles, cells' surface charge distribution was quantified from the fluorescence distribution. Two types of cells, human umbilical vein endothelial cells (HUVECs) and HeLa cells, were tested. From the measured surface charge density of a group of single cells, the average zeta potentials of the two types of cells were obtained, which are in good agreement with the standard electrophoretic light scattering measurement. This method can be used for rapid surface charge mapping of single particles or cells, and can advance cell-surface-charge characterization applications in many biomedical fields.
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Affiliation(s)
- Leixin Ouyang
- Department of Mechanical Engineering, University of Akron, Akron, OH 44325, USA; (L.O.); (R.X.)
| | - Rubia Shaik
- Department of Biomedical Engineering, University of Akron, Akron, OH 44325, USA; (R.S.); (G.Z.)
| | - Ruiting Xu
- Department of Mechanical Engineering, University of Akron, Akron, OH 44325, USA; (L.O.); (R.X.)
| | - Ge Zhang
- Department of Biomedical Engineering, University of Akron, Akron, OH 44325, USA; (R.S.); (G.Z.)
| | - Jiang Zhe
- Department of Mechanical Engineering, University of Akron, Akron, OH 44325, USA; (L.O.); (R.X.)
- Correspondence: ; Tel.: +1-330-972-7737
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76
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Qiu Y, Clarke M, Wan LTL, Lo JCK, Mason AJ, Lam JKW. Optimization of PEGylated KL4 Peptide for siRNA Delivery with Improved Pulmonary Tolerance. Mol Pharm 2021; 18:2218-2232. [PMID: 34014665 DOI: 10.1021/acs.molpharmaceut.0c01242] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Pulmonary delivery of small interfering RNA (siRNA) is a promising therapeutic strategy for treating various respiratory diseases but an effective carrier for the delivery of siRNA into the cells of the lungs and a robust gene-silencing effect is still lacking. Previously, we reported that the KL4 peptide, a synthetic cationic peptide with a repeating KLLLL sequence, can mediate effective siRNA transfection in lung epithelial cells but its high hydrophobic leucine content, and hence poor water solubility, limits its application as a delivery vector. Here, we show that the covalent attachment of monodisperse poly(ethylene glycol) (PEG) improves the solubility of KL4 and the uptake of its complex with siRNA into lung epithelial cells, such that very robust silencing is produced. All PEGylated KL4 peptides, with PEG length varying between 6 and 24 monomers, could bind and form nanosized complexes with siRNA, but the interaction between siRNA and peptides became weaker as the PEG chain length increased. All PEGylated KL4 peptides exhibited satisfactory siRNA transfection efficiency on three human lung epithelial cell lines, including A549 cells, Calu-3 cells, and BEAS-2B cells. The PEG12KL4 peptide, which contains 12 monomers of PEG, was optimal for siRNA delivery and also demonstrated a low risk of inflammatory response and toxicity in vivo following pulmonary administration.
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Affiliation(s)
- Yingshan Qiu
- Department of Pharmacology and Pharmacy, LKS Faculty of Medicine, The University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong SAR
| | - Maria Clarke
- Institute of Pharmaceutical Science, School of Cancer & Pharmaceutical Science, King's College London, Franklin-Wilkins Building, 150 Stamford Street, London SE1 9NH, United Kingdom
| | - Leon T L Wan
- Department of Pharmacology and Pharmacy, LKS Faculty of Medicine, The University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong SAR
| | - Jason C K Lo
- Department of Pharmacology and Pharmacy, LKS Faculty of Medicine, The University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong SAR
| | - A James Mason
- Institute of Pharmaceutical Science, School of Cancer & Pharmaceutical Science, King's College London, Franklin-Wilkins Building, 150 Stamford Street, London SE1 9NH, United Kingdom
| | - Jenny K W Lam
- Department of Pharmacology and Pharmacy, LKS Faculty of Medicine, The University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong SAR
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77
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Honarparvar S, Zhang X, Chen T, Alborzi A, Afroz K, Reible D. Frontiers of Membrane Desalination Processes for Brackish Water Treatment: A Review. MEMBRANES 2021; 11:246. [PMID: 33805438 PMCID: PMC8066301 DOI: 10.3390/membranes11040246] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 03/19/2021] [Accepted: 03/23/2021] [Indexed: 12/31/2022]
Abstract
Climate change, population growth, and increased industrial activities are exacerbating freshwater scarcity and leading to increased interest in desalination of saline water. Brackish water is an attractive alternative to freshwater due to its low salinity and widespread availability in many water-scarce areas. However, partial or total desalination of brackish water is essential to reach the water quality requirements for a variety of applications. Selection of appropriate technology requires knowledge and understanding of the operational principles, capabilities, and limitations of the available desalination processes. Proper combination of feedwater technology improves the energy efficiency of desalination. In this article, we focus on pressure-driven and electro-driven membrane desalination processes. We review the principles, as well as challenges and recent improvements for reverse osmosis (RO), nanofiltration (NF), electrodialysis (ED), and membrane capacitive deionization (MCDI). RO is the dominant membrane process for large-scale desalination of brackish water with higher salinity, while ED and MCDI are energy-efficient for lower salinity ranges. Selective removal of multivalent components makes NF an excellent option for water softening. Brackish water desalination with membrane processes faces a series of challenges. Membrane fouling and scaling are the common issues associated with these processes, resulting in a reduction in their water recovery and energy efficiency. To overcome such adverse effects, many efforts have been dedicated toward development of pre-treatment steps, surface modification of membranes, use of anti-scalant, and modification of operational conditions. However, the effectiveness of these approaches depends on the fouling propensity of the feed water. In addition to the fouling and scaling, each process may face other challenges depending on their state of development and maturity. This review provides recent advances in the material, architecture, and operation of these processes that can assist in the selection and design of technologies for particular applications. The active research directions to improve the performance of these processes are also identified. The review shows that technologies that are tunable and particularly efficient for partial desalination such as ED and MCDI are increasingly competitive with traditional RO processes. Development of cost-effective ion exchange membranes with high chemical and mechanical stability can further improve the economy of desalination with electro-membrane processes and advance their future applications.
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Affiliation(s)
- Soraya Honarparvar
- Department of Chemical Engineering, Texas Tech University, Lubbock, TX 79409, USA; (S.H.); (X.Z.); (T.C.); (K.A.)
| | - Xin Zhang
- Department of Chemical Engineering, Texas Tech University, Lubbock, TX 79409, USA; (S.H.); (X.Z.); (T.C.); (K.A.)
| | - Tianyu Chen
- Department of Chemical Engineering, Texas Tech University, Lubbock, TX 79409, USA; (S.H.); (X.Z.); (T.C.); (K.A.)
| | - Ashkan Alborzi
- Department of Civil, Environmental and Construction Engineering, Texas Tech University, Lubbock, TX 79409, USA;
| | - Khurshida Afroz
- Department of Chemical Engineering, Texas Tech University, Lubbock, TX 79409, USA; (S.H.); (X.Z.); (T.C.); (K.A.)
| | - Danny Reible
- Department of Chemical Engineering, Texas Tech University, Lubbock, TX 79409, USA; (S.H.); (X.Z.); (T.C.); (K.A.)
- Department of Civil, Environmental and Construction Engineering, Texas Tech University, Lubbock, TX 79409, USA;
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78
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Wang X, Liu K, Wu J. Demystifying the Stern layer at a metal-electrolyte interface: Local dielectric constant, specific ion adsorption, and partial charge transfer. J Chem Phys 2021; 154:124701. [PMID: 33810643 DOI: 10.1063/5.0043963] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Electric double layer (EDL) represents one of the most basic concepts in electrochemistry and is pertinent to diverse engineering applications ranging from electrocatalysis to energy storage. Whereas phenomenological and coarse-grained models have been long established to describe ionic distributions in the diffuse layer, a faithful prediction of the physicochemical properties of the electrode-electrolyte interface from a molecular perspective remains a daunting challenge. In this work, we investigate the charging behavior of an Ag (111) electrode in NaF aqueous solutions leveraging experimental results and theoretical calculations based on the classical density functional theory for ion distributions in the diffuse layer and on the joint density functional theory (JDFT) for the electronic structure. When the Ag electrode is applied with a negative voltage, the surface charge density can be reasonably described by assuming a neutral Stern layer with the dielectric constant dependent on the local electric field as predicted by the Kirkwood equation. However, the specific adsorption of F- ions must be considered when the electrode is positively charged and the fluoride adsorption can be attributed to both physical and chemical interactions. Qualitatively, F- binding and partial charge transfer are supported by JDFT calculations, which predict an increased binding energy as the voltage increases. Our findings shed insight on the molecular characteristics of the Stern layer and the charge behavior of adsorbed species not specified by conventional EDL models.
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Affiliation(s)
- Xuepeng Wang
- Department of Chemical and Environmental Engineering, University of California, Riverside, Riverside, California 92521, USA
| | - Kun Liu
- Department of Chemical and Environmental Engineering, University of California, Riverside, Riverside, California 92521, USA
| | - Jianzhong Wu
- Department of Chemical and Environmental Engineering, University of California, Riverside, Riverside, California 92521, USA
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79
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Rehl B, Gibbs JM. Role of Ions on the Surface-Bound Water Structure at the Silica/Water Interface: Identifying the Spectral Signature of Stability. J Phys Chem Lett 2021; 12:2854-2864. [PMID: 33720727 DOI: 10.1021/acs.jpclett.0c03565] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Isolating the hydrogen-bonding structure of water immediately at the surface is challenging, even with surface-specific techniques like sum-frequency generation (SFG), because of the presence of aligned water further away in the diffuse layer. Here, we combine zeta potential and SFG intensity measurements with the maximum entropy method referenced to reported phase-sensitive SFG and second-harmonic generation results to deconvolute the SFG spectral contributions of the surface waters from those in the diffuse layer. Deconvolution reveals that at very low ionic strength, the surface water structure is similar to that of a neutral silica surface near the point-of-zero-charge with waters in different hydrogen-bonding environments oriented in opposite directions. This similarity suggests that the known metastability of silica colloids against aggregation under both conditions could arise from this distinct surface water structure. Upon the addition of salt, significant restructuring of water is observed, leading to a net decrease in order at the surface.
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Affiliation(s)
- Benjamin Rehl
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Julianne M Gibbs
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
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80
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Zhu X, Zhu L, Li H, Xue J, Ma C, Yin Y, Qiao X, Sun D, Xue Q. Multifunctional charged hydrogel nanofibrous membranes for metal ions contained emulsified oily wastewater purification. J Memb Sci 2021. [DOI: 10.1016/j.memsci.2020.118950] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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81
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Schneider S, Säckel C, Brodrecht M, Breitzke H, Buntkowsky G, Vogel M. NMR studies on the influence of silica confinements on local and diffusive dynamics in LiCl aqueous solutions approaching their glass transitions. J Chem Phys 2020; 153:244501. [PMID: 33380090 DOI: 10.1063/5.0036079] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
We use 1H, 2H, and 7Li NMR to investigate the molecular dynamics of glass-forming LiCl-7H2O and LiCl-7D2O solutions confined to MCM-41 or SBA-15 silica pores with diameters in the range of d = 2.8 nm-5.4 nm. Specifically, it is exploited that NMR experiments in homogeneous and gradient magnetic fields provide access to local and diffusive motions, respectively, and that the isotope selectivity of the method allows us to characterize the dynamics of the water molecules and the lithium ions separately. We find that the silica confinements cause a slowdown of the dynamics on all length scales, which is stronger at lower temperatures and in narrower pores and is more prominent for the lithium ions than the water molecules. However, we do not observe a temperature-dependent decoupling of short-range and long-range dynamics inside the pores. 7Li NMR correlation functions show bimodal decays when the pores are sufficiently wide (d > 3 nm) so that bulk-like ion dynamics in the pore centers can be distinguished from significantly retarded ion dynamics at the pore walls, possibly in a Stern layer. However, we do not find evidence for truly immobile fractions of water molecules or lithium ions and, hence, for the existence of a static Stern layer in any of the studied silica pores.
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Affiliation(s)
- S Schneider
- Institute of Condensed Matter Physics, Technische Universität Darmstadt, Hochschulstr. 6, 64289 Darmstadt, Germany
| | - C Säckel
- Institute of Condensed Matter Physics, Technische Universität Darmstadt, Hochschulstr. 6, 64289 Darmstadt, Germany
| | - M Brodrecht
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, Alarich-Weiss-Str. 8, 64287 Darmstadt, Germany
| | - H Breitzke
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, Alarich-Weiss-Str. 8, 64287 Darmstadt, Germany
| | - G Buntkowsky
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, Alarich-Weiss-Str. 8, 64287 Darmstadt, Germany
| | - M Vogel
- Institute of Condensed Matter Physics, Technische Universität Darmstadt, Hochschulstr. 6, 64289 Darmstadt, Germany
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82
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Martin DJ, Johnson SI, Mercado BQ, Raugei S, Mayer JM. Intramolecular Electrostatic Effects on O2, CO2, and Acetate Binding to a Cationic Iron Porphyrin. Inorg Chem 2020; 59:17402-17414. [DOI: 10.1021/acs.inorgchem.0c02703] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Daniel J. Martin
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | - Samantha I. Johnson
- Pacific Northwest National Laboratory (PNNL), Richland, Washington 99352, United States
| | - Brandon Q. Mercado
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | - Simone Raugei
- Pacific Northwest National Laboratory (PNNL), Richland, Washington 99352, United States
| | - James M. Mayer
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
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83
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Bonyadi SZ, Demott CJ, Grunlan MA, Dunn AC. Cartilage-like tribological performance of charged double network hydrogels. J Mech Behav Biomed Mater 2020; 114:104202. [PMID: 33243694 DOI: 10.1016/j.jmbbm.2020.104202] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Revised: 10/16/2020] [Accepted: 11/06/2020] [Indexed: 10/23/2022]
Abstract
A synthetic hydrogel material may offer utility as a cartilage replacement if it is able to maintain low friction in different sliding environments and achieve bulk mechanical properties to withstand the severe environment of the joint. In this work, we compared the tribological behavior of four double network (DN) hydrogels to that of fresh porcine cartilage in both water and fetal bovine serum (FBS). The DN hydrogels were comprised of a negatively charged 1st network and a 2nd network wherein comonomers of varying charge (i.e. neutral, positive, negative, and zwitterionic) were introduced at 10 wt% to an otherwise neutral network. A steel ball probe was used to perform microindentation tests to determine the surface elastic modulus of the samples and estimate their contact areas during sliding. Friction tests using a stationary probe with a stage that reciprocated at a range of speeds were performed to develop lubrication curves in both water and FBS. We found that the DN hydrogels with a neutral or zwitterionic 2nd network had the lowest friction and shear stresses, notably below that of cartilage. The differences in charge and structure of the samples were more evident in water than in FBS, as the lubrication responses for all the hydrogels spanned a wider range of values. In FBS, the lubrication responses were pushed towards elasto-hydrodynamics with nearly all friction coefficient values falling below 0.3. This indicates that the FBS interacts with the hydrogels and cartilage samples in a similar manner as that of cartilage by maintaining a robust layer of solution at the interface during sliding. These DN hydrogels prove to fulfill, and in some cases surpass, the lubrication demands for cartilage replacement in load bearing joints.
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Affiliation(s)
- Shabnam Z Bonyadi
- Department of Mechanical Science & Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Connor J Demott
- Department of Biomedical Engineering, Texas A&M University, College Station, TX, USA
| | - Melissa A Grunlan
- Department of Biomedical Engineering, Texas A&M University, College Station, TX, USA; Department of Materials Science & Engineering, Texas A&M University, College Station, TX, USA; Department of Chemistry, Texas A&M University, College Station, TX, USA
| | - Alison C Dunn
- Department of Mechanical Science & Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
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84
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Yun J, Wang Y, Liu Z, Li Y, Yang H, Xu ZL. High efficient dye removal with hydrolyzed ethanolamine-Polyacrylonitrile UF membrane: Rejection of anionic dye and selective adsorption of cationic dye. CHEMOSPHERE 2020; 259:127390. [PMID: 32593817 DOI: 10.1016/j.chemosphere.2020.127390] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 06/08/2020] [Accepted: 06/10/2020] [Indexed: 05/25/2023]
Abstract
The dye-water treatment using UF membrane is still a challenge. In the present study, the optimized PAN-ETA ultrafiltration membrane was hydrolyzed and subsequently characterized by SEM, IR, CA, XPS, NMR, mechanic measurement, etc. The obtained membrane (H-PAN-ETA) was used for dye removal and it showed both an excellent anti-dye fouling and a good rejection property for anionic dyes. I.e. 96% rejection for methyl blue (MB), 99% for congo red (CR), 94% for acid fuchsin (AF) with no sign of contamination by dye. The flux of H-PAN-ETA membrane maintained at 50-53 L m-2⋅ h-1 during a 10-h filtration, which is higher than that of tight UF membranes reported. Meanwhile, H-PAN-ETA membrane was able to selectively remove cationic dyes, such as methylene blue (MEB), rhodamine B (RB) and, crystal violet (CV), or the mixture of anionic dye/cationic dye by adsorption process. Its adsorption capacity remained unchanged after 20 cycles. Finally, the immobile electrical double layer (EDL) theory combined with electrostatic force was introduced to explain the separation mechanism of charged UF membrane, which is helpful to instruct the preparation of UF membrane for dye removal.
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Affiliation(s)
- Jianhua Yun
- State Key Laboratory of Chemical Engineering, Membrane Science and Engineering R&D Lab, Chemical Engineering Research Center, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China
| | - Yixing Wang
- State Key Laboratory of Chemical Engineering, Membrane Science and Engineering R&D Lab, Chemical Engineering Research Center, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China
| | - Zhenying Liu
- State Key Laboratory of Chemical Engineering, Membrane Science and Engineering R&D Lab, Chemical Engineering Research Center, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China
| | - Yujie Li
- State Key Laboratory of Chemical Engineering, Membrane Science and Engineering R&D Lab, Chemical Engineering Research Center, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China
| | - Hu Yang
- State Key Laboratory of Chemical Engineering, Membrane Science and Engineering R&D Lab, Chemical Engineering Research Center, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China.
| | - Zhen-Liang Xu
- State Key Laboratory of Chemical Engineering, Membrane Science and Engineering R&D Lab, Chemical Engineering Research Center, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China
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85
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Patra CN. Size and charge correlations in spherical electric double layers: a case study with fully asymmetric mixed electrolytes within the solvent primitive model. RSC Adv 2020; 10:39017-39025. [PMID: 35518397 PMCID: PMC9057371 DOI: 10.1039/d0ra06145j] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 10/05/2020] [Indexed: 11/21/2022] Open
Abstract
Size and charge correlations in spherical electric double layers are investigated through Monte Carlo simulations and density functional theory, through a solvent primitive model representation. A fully asymmetric mixed electrolyte is used for the small ions, whereas the solvent, apart from being a continuum dielectric, is also treated as an individual component. A partially perturbative density functional theory is adopted here, and for comparison, a standard canonical ensemble Monte Carlo simulation is used. The hard-sphere free energy is treated within a weighted density approach and the residual ionic contribution is estimated through perturbation around the uniform density. The results from both methods corroborate each other quantitatively over a wide range of physical parameters. The importance of structural correlations is envisaged through the size and charge asymmetry of the supporting electrolytes that includes the solvent as a component. Size and charge correlations in spherical electric double layers are investigated through Monte Carlo simulations and density functional theory, through a solvent primitive model representation.![]()
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Affiliation(s)
- Chandra N Patra
- Theoretical Chemistry Section, Chemistry Group, Bhabha Atomic Research Centre Mumbai 400 085 India
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86
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Miao B, Sangaré K, Iqbal A, Marsan B, Bevan KH. Interpreting interfacial semiconductor-liquid capacitive characteristics impacted by surface states: a theoretical and experimental study of CuGaS 2. Phys Chem Chem Phys 2020; 22:19631-19642. [PMID: 32869781 DOI: 10.1039/d0cp02888f] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Semiconductor-liquid interfaces are essential to the operation of many energy devices. Crucially, the operational characteristics of such devices are dependent upon both the flat band potential and doping concentration present in their solid-state semiconducting region. Traditionally, capacitive "linear" Mott-Schottky plots have often been utilized to extract these two parameters. However, significant concentrations of surface states within semiconductor-liquid junctions can give rise to strong non-linearities that prevent an effective linearity-based analysis. In this work, we detail a theoretical approach for estimating both the doping concentration and flat band potential from the capacitive characteristics of semiconductor-liquid junctions heavily impacted upon by surface states. Our theoretical approach is applied to CuGaS2 immersed in an aqueous electrolyte, for which excellent convergent values of the doping concentration and flat band potential are obtained across a wide range of impedance measurement frequencies. The results suggest a marked improvement over a linearity-based approach that could assist the analysis of many types of semiconductor-liquid junctions subject to high concentrations of surface states.
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Affiliation(s)
- Botong Miao
- Division of Materials Engineering, Faculty of Engineering, McGill University, Montréal, Québec, Canada.
| | - Kassoum Sangaré
- Département de chimie, Université du Québec à Montréal, Montréal, Québec, Canada.
| | - Asif Iqbal
- Division of Materials Engineering, Faculty of Engineering, McGill University, Montréal, Québec, Canada.
| | - Benoît Marsan
- Département de chimie, Université du Québec à Montréal, Montréal, Québec, Canada.
| | - Kirk H Bevan
- Division of Materials Engineering, Faculty of Engineering, McGill University, Montréal, Québec, Canada. and Centre for the Physics of Materials, McGill University, Montréal, Québec, Canada
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87
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Gschwend GC, Girault HH. Discrete Helmholtz model: a single layer of correlated counter-ions. Metal oxides and silica interfaces, ion-exchange and biological membranes. Chem Sci 2020; 11:10304-10312. [PMID: 34094294 PMCID: PMC8162434 DOI: 10.1039/d0sc03748f] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 09/09/2020] [Indexed: 01/31/2023] Open
Abstract
The mechanism by which interfaces in solution can be polarised depends on the nature of the charge carriers. In the case of a conductor, the charge carriers are electrons and the polarisation is homogeneous in the plane of the electrode. In the case of an insulator covered by ionic moieties, the polarisation is inhomogeneous and discrete in the plane of the interface. Despite these fundamental differences, these systems are usually treated in the same theoretical framework that relies on the Poisson-Boltzmann equation for the solution side. In this perspective, we show that interfaces polarised by discrete charge distributions are rather ubiquitous and that their associated potential drop significantly differs from those of conductor-electrolyte interfaces. We show that these configurations, spanning liquid-liquid interfaces, charged silica-water interfaces, metal oxide interfaces, supercapacitors, ion-exchange membranes and even biological membranes can be uniformly treated under a common "Discrete Helmholtz" model where the discrete charges are compensated by a single layer of correlated counter-ions, thereby generating a sharp potential drop at the interface.
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Affiliation(s)
- Grégoire C Gschwend
- Laboratoire d'Electrochimie Physique et Analytique (LEPA), École Polytechnique Fédérale de Lausanne (EPFL) Rue de l'Industrie 17 CH-1951 Sion Switzerland
| | - Hubert H Girault
- Laboratoire d'Electrochimie Physique et Analytique (LEPA), École Polytechnique Fédérale de Lausanne (EPFL) Rue de l'Industrie 17 CH-1951 Sion Switzerland
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88
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Besford QA, Christofferson AJ, Kalayan J, Sommer JU, Henchman RH. The Attraction of Water for Itself at Hydrophobic Quartz Interfaces. J Phys Chem B 2020; 124:6369-6375. [PMID: 32589426 DOI: 10.1021/acs.jpcb.0c04545] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Structural forces within aqueous water at a solid interface can significantly change surface reactivity and the affinity of solutes toward it. We show using molecular dynamics simulations how hydrophilic and hydrophobic quartz surfaces perturb the orientational structure of aqueous water, ultimately strengthening dipolar forces between molecules in proximity to the interface. When derived as a function of distance from each surface, it was found that both surfaces indirectly enhance the long-range dipolar attraction of water for itself toward the interfacial region. This was found to be longer-ranged for water molecules solvating the hydrophobic surface than those solvating the hydrophilic surface, with a range of up to 2.5 nm from the hydrophobic surface. Our results give direct quantification of surface-induced changes in solvent-solvent attraction, ultimately providing a counterintuitive addition to the balance of hydrophobic forces at aqueous-solid interfaces.
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Affiliation(s)
- Quinn A Besford
- Institute of Physical Chemistry and Polymer Physics, Leibniz Institute for Polymer Research Dresden e.V., Hohe Str. 6, 01069 Dresden, Germany
| | | | - Jas Kalayan
- Manchester Institute of Biotechnology, The University of Manchester, Manchester M13 9PL, U.K.,School of Chemistry, The University of Manchester, Oxford M13 9PL, U.K
| | - Jens-Uwe Sommer
- Institute Theory of Polymers, Leibniz Institute for Polymer Research Dresden e.V., Hohe Str. 6, 01069 Dresden, Germany
| | - Richard H Henchman
- Manchester Institute of Biotechnology, The University of Manchester, Manchester M13 9PL, U.K.,School of Chemistry, The University of Manchester, Oxford M13 9PL, U.K
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89
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Shoaib M, Quadri SMR, Wani OB, Bobicki E, Garrido GI, Elkamel A, Abdala A. Adsorption of enhanced oil recovery polymer, schizophyllan, over carbonate minerals. Carbohydr Polym 2020; 240:116263. [PMID: 32475555 DOI: 10.1016/j.carbpol.2020.116263] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 03/30/2020] [Accepted: 04/05/2020] [Indexed: 02/06/2023]
Abstract
Schizophyllan is a natural polysaccharide that has shown great potential as enhanced oil recovery (EOR) polymer for high-temperature, high-salinity reservoirs. Nevertheless, the adsorption behavior of schizophyllan over carbonate minerals remains ambiguous element towards its EOR applications. Here, we investigate the adsorption of schizophyllan on different carbonate minerals. The effect of mineral type, salinity, and background ions on adsorption is analyzed. Our results indicate the adsorption capacity is higher on calcite and dolomite compared to silica and kaolin and the adsorption capacity decreases with salinity. Moreover, the adsorption kinetics follows pseudo-second order mechanism regardless of the mineral type. Adsorption over calcite is diminished in presence of water structure making ions and enhanced in presence of structure breaking ion and in presence of urea. Gel permeation chromatography results reveal the preferential adsorption of longer chains. The adsorption over carbonate minerals proceed via complex formation between polymer molecule and mineral surface.
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Affiliation(s)
- Mohammad Shoaib
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Canada
| | | | - Omar Bashir Wani
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Canada
| | - Erin Bobicki
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Canada
| | | | - Ali Elkamel
- Department of Chemical Engineering, University of Waterloo, Ontario, Canada; Department of Chemical Engineering, Khalifa University, Abu Dhabi, United Arab Emirates
| | - Ahmed Abdala
- Chemical Engineering Program, Texas A&M University at Qatar, Doha, Qatar.
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90
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Zhao C, Zhang H, Hou J, Ou R, Zhu Y, Li X, Jiang L, Wang H. Effect of Anion Species on Ion Current Rectification Properties of Positively Charged Nanochannels. ACS APPLIED MATERIALS & INTERFACES 2020; 12:28915-28922. [PMID: 32460478 DOI: 10.1021/acsami.0c08263] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Biological ion channels can realize delicate mass transport under complicated physiological conditions. Artificial nanochannels can achieve biomimetic ion current rectification (ICR), gating, and selectivity that are mostly performed in pure salt solutions. Synthetic nanochannels that can function under mixed ion systems are highly desirable, yet their performances are hard to be compared to those under pure systems. Seeking out the potential reasons by investigating the effect of mixed-system components on the ion-transport properties of the constructed nanochannels seems necessary and important. Herein, we report the effect of anions with different charges and sizes on the ICR properties of positively charged nanochannels. Among the investigated anions, the low-valent anions showed no impact on the ICR direction, while the high-valent component ferrocyanide [Fe(CN)64-] caused significant ICR inversion. The ICR inversion mechanism is evidenced to result from the adsorption of Fe(CN)64--induced surface charge reversal, which relates to solution concentration, pH conditions, and nanochannel sizes and applies to both aminated and quaternized nanochannels that are positively charged. Noticeably, Fe(CN)64- is found to interfere with the transport of protein molecules in the nanochannel. This work points out that the ion species from mixed systems would potentially impact the intrinsic ICR properties of the nanochannels. Replacing highly charged counterions with organic components would be promising in building up future nanochannel-based mass transport systems running under mixed systems.
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Affiliation(s)
- Chen Zhao
- Department of Chemical Engineering, Monash University, Clayton, Melbourne, Victoria 3800, Australia
| | - Huacheng Zhang
- Department of Chemical Engineering, Monash University, Clayton, Melbourne, Victoria 3800, Australia
| | - Jue Hou
- Department of Chemical Engineering, Monash University, Clayton, Melbourne, Victoria 3800, Australia
| | - Ranwen Ou
- Department of Chemical Engineering, Monash University, Clayton, Melbourne, Victoria 3800, Australia
| | - Yinlong Zhu
- Department of Chemical Engineering, Monash University, Clayton, Melbourne, Victoria 3800, Australia
| | - Xingya Li
- Department of Chemical Engineering, Monash University, Clayton, Melbourne, Victoria 3800, Australia
| | - Lei Jiang
- Department of Chemical Engineering, Monash University, Clayton, Melbourne, Victoria 3800, Australia
- Key Laboratory of Bioinspired Materials and Interfacial Science, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Huanting Wang
- Department of Chemical Engineering, Monash University, Clayton, Melbourne, Victoria 3800, Australia
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91
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Xiong H, Devegowda D, Huang L. Oil–water
transport in
clay‐hosted
nanopores: Effects of
long‐range
electrostatic forces. AIChE J 2020. [DOI: 10.1002/aic.16276] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Hao Xiong
- Mewbourne School of Petroleum and Geological EngineeringThe University of Oklahoma Norman Oklahoma USA
| | - Deepak Devegowda
- Mewbourne School of Petroleum and Geological EngineeringThe University of Oklahoma Norman Oklahoma USA
| | - Liangliang Huang
- Chemical, Biological & Materials EngineeringThe University of Oklahoma Norman Oklahoma USA
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92
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Bischoff M, Biriukov D, Předota M, Roke S, Marchioro A. Surface Potential and Interfacial Water Order at the Amorphous TiO 2 Nanoparticle/Aqueous Interface. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2020; 124:10961-10974. [PMID: 35592180 PMCID: PMC9109959 DOI: 10.1021/acs.jpcc.0c01158] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 04/21/2020] [Indexed: 05/11/2023]
Abstract
Colloidal nanoparticles exhibit unique size-dependent properties differing from their bulk counterpart, which can be particularly relevant for catalytic applications. To optimize surface-mediated chemical reactions, the understanding of the microscopic structure of the nanoparticle-liquid interface is of paramount importance. Here we use polarimetric angle-resolved second harmonic scattering (AR-SHS) to determine surface potential values as well as interfacial water orientation of ∼100 nm diameter amorphous TiO2 nanoparticles dispersed in aqueous solutions, without any initial assumption on the distribution of interfacial charges. We find three regions of different behavior with increasing NaCl concentration. At very low ionic strengths (0-10 μM), the Na+ ions are preferentially adsorbed at the TiO2 surface as inner-sphere complexes. At low ionic strengths (10-100 μM), a distribution of counterions equivalent to a diffuse layer is observed, while at higher ionic strengths (>100 μM), an additional layer of hydrated condensed ions is formed. We find a similar behavior for TiO2 nanoparticles in solutions of different basic pH. Compared to identically sized SiO2 nanoparticles, the TiO2 interface has a higher affinity for Na+ ions, which we further confirm with molecular dynamics simulations. With its ability to monitor ion adsorption at the surface with micromolar sensitivity and changes in the surface potential, AR-SHS is a powerful tool to investigate interfacial properties in a variety of catalytic and photocatalytic applications.
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Affiliation(s)
- Marie Bischoff
- Laboratory
for fundamental BioPhotonics (LBP), Institute of Bioengineering (IBI),
and Institute of Materials
Science (IMX), School of Engineering (STI), École polytechnique fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Denys Biriukov
- Institute
of Physics, Faculty of Science, University
of South Bohemia, 370 05 České Budějovice, Czech
Republic
| | - Milan Předota
- Institute
of Physics, Faculty of Science, University
of South Bohemia, 370 05 České Budějovice, Czech
Republic
| | - Sylvie Roke
- Laboratory
for fundamental BioPhotonics (LBP), Institute of Bioengineering (IBI),
and Institute of Materials
Science (IMX), School of Engineering (STI), École polytechnique fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- E-mail:
| | - Arianna Marchioro
- Laboratory
for fundamental BioPhotonics (LBP), Institute of Bioengineering (IBI),
and Institute of Materials
Science (IMX), School of Engineering (STI), École polytechnique fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- E-mail:
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93
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Molecular Mean-Field Theory of Ionic Solutions: A Poisson-Nernst-Planck-Bikerman Model. ENTROPY 2020; 22:e22050550. [PMID: 33286322 PMCID: PMC7517072 DOI: 10.3390/e22050550] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 05/11/2020] [Accepted: 05/12/2020] [Indexed: 12/21/2022]
Abstract
We have developed a molecular mean-field theory—fourth-order Poisson–Nernst–Planck–Bikerman theory—for modeling ionic and water flows in biological ion channels by treating ions and water molecules of any volume and shape with interstitial voids, polarization of water, and ion-ion and ion-water correlations. The theory can also be used to study thermodynamic and electrokinetic properties of electrolyte solutions in batteries, fuel cells, nanopores, porous media including cement, geothermal brines, the oceanic system, etc. The theory can compute electric and steric energies from all atoms in a protein and all ions and water molecules in a channel pore while keeping electrolyte solutions in the extra- and intracellular baths as a continuum dielectric medium with complex properties that mimic experimental data. The theory has been verified with experiments and molecular dynamics data from the gramicidin A channel, L-type calcium channel, potassium channel, and sodium/calcium exchanger with real structures from the Protein Data Bank. It was also verified with the experimental or Monte Carlo data of electric double-layer differential capacitance and ion activities in aqueous electrolyte solutions. We give an in-depth review of the literature about the most novel properties of the theory, namely Fermi distributions of water and ions as classical particles with excluded volumes and dynamic correlations that depend on salt concentration, composition, temperature, pressure, far-field boundary conditions etc. in a complex and complicated way as reported in a wide range of experiments. The dynamic correlations are self-consistent output functions from a fourth-order differential operator that describes ion-ion and ion-water correlations, the dielectric response (permittivity) of ionic solutions, and the polarization of water molecules with a single correlation length parameter.
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94
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Mai VP, Yang RJ. Active control of salinity-based power generation in nanopores using thermal and pH effects. RSC Adv 2020; 10:18624-18631. [PMID: 35518343 PMCID: PMC9053878 DOI: 10.1039/d0ra02329a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Accepted: 05/07/2020] [Indexed: 01/12/2023] Open
Abstract
Harvesting blue energy from saline solutions has attracted much attention recently. Salinity-based power generation in nanopores is governed by both passive factors (e.g., the nanopore diameter, nanopore length, nanopore material, and pore density) and active factors (e.g., the concentration gradient, temperature, and pH environment). The present study performs COMSOL multiphysics numerical simulations based on the Poisson–Nernst–Planck equations, Navier–Stokes equations and heat transfer equation to examine the combined effects of the temperature gradient and pH level on the diffusion voltage and maximum power generation in single silica nanopores with lengths of 100 nm and 500 nm, respectively. In performing the simulations, the pH value is adjusted in the range of pH 5–11, the salinity concentration gradient is 100-fold and 1000-fold, respectively. Three different thermal conditions are considered, namely (1) isothermal-room temperature (298 K); (2) asymmetric thermal (temperature of low-concentration reservoir and high-concentration reservoir are 323 K and 298 K, respectively); and (3) isothermal-high temperature (323 K). The results show that the generated power varies significantly with both the pH level and the temperature conditions. In particular, the asymmetric thermal condition yields an effective improvement in the power generation performance since it reduces the surface charge density on the surface of the nanopore near the low-concentration end and therefore suppresses the ion concentration polarization (ICP) effect. The improvement in the energy harvesting performance is particularly apparent at pH levels in the range of 9–10 (about 100% higher than that of pH 7). Overall, the results confirm the feasibility of using active factors to enhance the power generation performance of salinity gradient-based nanopore systems. The combined effects of pH and thermal conditions on enhancing blue energy harvesting through nanopores are investigated.![]()
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Affiliation(s)
- Van-Phung Mai
- Department of Engineering Science, National Cheng Kung University Tainan Taiwan +886-6-2766549 +886-6-2757575 extn 63343
| | - Ruey-Jen Yang
- Department of Engineering Science, National Cheng Kung University Tainan Taiwan +886-6-2766549 +886-6-2757575 extn 63343
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95
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Rimsza JM, Kuhlman KL. Surface Energies and Structure of Salt-Brine Interfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:2482-2491. [PMID: 32097016 DOI: 10.1021/acs.langmuir.9b03172] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Permeability of salt formations is controlled by the equilibrium between the salt-brine and salt-salt interfaces described by the dihedral angle, which can change with the composition of the intergranular brine. Here, classical molecular dynamics (MD) simulations were used to investigate the structure and properties of the salt-brine interface to provide insight into the stability of salt systems. Mixed NaCl-KCl brines were investigated to explore differences in ion size on the surface energy and interface structure. Nonlinearity was noted in the salt-brine surface energy with increasing KCl concentration, and the addition of 10% KCl increased surface energies by 2-3 times (5.0 M systems). Size differences in Na+ and K+ ions altered the packing of dissolved ions and water molecules at the interface, impacting the surface energy. Additionally, ions at the interface had lower numbers of coordinating water molecules than those in the bulk and increased hydration for ions in systems with 100% NaCl or 100% KCl brines. Ultimately, small changes in brine composition away from pure NaCl altered the structure of the salt-brine interface, impacting the dihedral angle and the predicted equilibrium permeability of salt formations.
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Affiliation(s)
- Jessica M Rimsza
- Geochemistry Department, Sandia National Laboratories, Albuquerque, New Mexico 87123, United States
| | - Kristopher L Kuhlman
- Applied Systems Analysis & Research, Sandia National Laboratories, Albuquerque, New Mexico 87123, United States
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96
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Shih YJ, Dong CD, Huang YH, Huang CP. Loofah-derived activated carbon supported on nickel foam (AC/Ni) electrodes for the electro-sorption of ammonium ion from aqueous solutions. CHEMOSPHERE 2020; 242:125259. [PMID: 31896176 DOI: 10.1016/j.chemosphere.2019.125259] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 10/17/2019] [Accepted: 10/28/2019] [Indexed: 06/10/2023]
Abstract
Activated carbon (AC), prepared from dried loofah sponge, was supported on nickel foam to fabricate AC/Ni electrodes. The characteristics of ammonium electrosorption on AC/Ni electrodes was studied. Results showed that AC prepared in one-step activation (without pre-pyrolysis), i.e., OAC, had relatively low crystallinity, high mesoporosity, and high specific capacitance compared to those made in two-step carbonation followed by activation. Adsorption and desorption density of NH4+ were measured at constant potential of -1.0 V (vs. Hg/HgO) and +0.1 V (vs. Hg/HgO), respectively. Non-faradaic charging contributed to the electrochemical storage and adsorption of ammonium ions on the AC surface with a maximal charge efficiency of 80%, at an applied potential of -1.0 V (vs. Hg/HgO). Multiple-layer adsorption isotherm better described the electrosorption of ammonium ion on OAC/Ni electrodes yielding a maximum adsorption capacity of 6 mg-N g-1, which was comparable with other similar systems. Overall, results clearly demonstrated the effect of synthesis strategy on the capacitive charging behaviors of AC/Ni electrodes and its relationship to NH4+ electrosorption.
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Affiliation(s)
- Yu-Jen Shih
- Institute of Environmental Engineering, National Sun Yat-sen University, Kaohsiung, 804, Taiwan.
| | - Cheng-Di Dong
- Department of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung, 811, Taiwan
| | - Yao-Hui Huang
- Department of Chemical Engineering, National Cheng-Kung University, Tainan, 701, Taiwan
| | - C P Huang
- Department of Civil and Environmental Engineering, University of Delaware, Newark, DE, 19716, USA.
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97
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Cation-controlled wetting properties of vermiculite membranes and its promise for fouling resistant oil-water separation. Nat Commun 2020; 11:1097. [PMID: 32107369 PMCID: PMC7046718 DOI: 10.1038/s41467-020-14854-4] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Accepted: 02/07/2020] [Indexed: 11/08/2022] Open
Abstract
Manipulating the surface energy, and thereby the wetting properties of solids, has promise for various physical, chemical, biological and industrial processes. Typically, this is achieved by either chemical modification or by controlling the hierarchical structures of surfaces. Here we report a phenomenon whereby the wetting properties of vermiculite laminates are controlled by the hydrated cations on the surface and in the interlamellar space. We find that vermiculite laminates can be tuned from superhydrophilic to hydrophobic simply by exchanging the cations; hydrophilicity decreases with increasing cation hydration free energy, except for lithium. The lithium-exchanged vermiculite laminate is found to provide a superhydrophilic surface due to its anomalous hydrated structure at the vermiculite surface. Building on these findings, we demonstrate the potential application of superhydrophilic lithium exchanged vermiculite as a thin coating layer on microfiltration membranes to resist fouling, and thus, we address a major challenge for oil–water separation technology. Manipulation of surface energy and wetting properties of solids may impact a variety of processes, including membrane fouling. Here the authors tune properties of vermiculite laminates from superhydrophilic to hydrophobic by cation exchange, and demonstrate potential for fouling resistant oil–water separation.
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98
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Lin K, Lin CY, Polster JW, Chen Y, Siwy ZS. Charge Inversion and Calcium Gating in Mixtures of Ions in Nanopores. J Am Chem Soc 2020; 142:2925-2934. [DOI: 10.1021/jacs.9b11537] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Kabin Lin
- Department of Physics and Astronomy, University of California, Irvine, California 92697, United States
- Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, School of Mechanical Engineering, Southeast University, Nanjing, 211189, China
| | - Chih-Yuan Lin
- Department of Physics and Astronomy, University of California, Irvine, California 92697, United States
| | - Jake W. Polster
- Department of Chemistry, University of California, Irvine, California 92697, United States
| | - Yunfei Chen
- Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, School of Mechanical Engineering, Southeast University, Nanjing, 211189, China
| | - Zuzanna S. Siwy
- Department of Physics and Astronomy, University of California, Irvine, California 92697, United States
- Department of Chemistry, University of California, Irvine, California 92697, United States
- Department of Biomedical Engineering, University of California, Irvine, California 92697, United States
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99
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Lin S, Xu L, Chi Wang A, Wang ZL. Quantifying electron-transfer in liquid-solid contact electrification and the formation of electric double-layer. Nat Commun 2020; 11:399. [PMID: 31964882 PMCID: PMC6972942 DOI: 10.1038/s41467-019-14278-9] [Citation(s) in RCA: 141] [Impact Index Per Article: 35.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 12/16/2019] [Indexed: 12/04/2022] Open
Abstract
Contact electrification (CE) has been known for more than 2600 years but the nature of charge carriers and their transfer mechanisms still remain poorly understood, especially for the cases of liquid-solid CE. Here, we study the CE between liquids and solids and investigate the decay of CE charges on the solid surfaces after liquid-solid CE at different thermal conditions. The contribution of electron transfer is distinguished from that of ion transfer on the charged surfaces by using the theory of electron thermionic emission. Our study shows that there are both electron transfer and ion transfer in the liquid-solid CE. We reveal that solutes in the solution, pH value of the solution and the hydrophilicity of the solid affect the ratio of electron transfers to ion transfers. Further, we propose a two-step model of electron or/and ion transfer and demonstrate the formation of electric double-layer in liquid-solid CE.
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Affiliation(s)
- Shiquan Lin
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing, 100083, PR China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Liang Xu
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing, 100083, PR China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Aurelia Chi Wang
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA, 30332-0245, USA
| | - Zhong Lin Wang
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing, 100083, PR China.
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing, 100049, PR China.
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA, 30332-0245, USA.
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100
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Chang H, Ohno PE, Liu Y, Lozier EH, Dalchand N, Geiger FM. Direct Measurement of Charge Reversal on Lipid Bilayers Using Heterodyne-Detected Second Harmonic Generation Spectroscopy. J Phys Chem B 2020; 124:641-649. [DOI: 10.1021/acs.jpcb.9b09341] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- HanByul Chang
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60660, United States
| | - Paul E. Ohno
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60660, United States
| | - Yangdongling Liu
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60660, United States
| | - Emilie H. Lozier
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60660, United States
| | - Naomi Dalchand
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60660, United States
| | - Franz M. Geiger
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60660, United States
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