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Araste F, Aliabadi A, Abnous K, Taghdisi SM, Ramezani M, Alibolandi M. Self-assembled polymeric vesicles: Focus on polymersomes in cancer treatment. J Control Release 2021; 330:502-528. [DOI: 10.1016/j.jconrel.2020.12.027] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2020] [Revised: 12/15/2020] [Accepted: 12/16/2020] [Indexed: 12/16/2022]
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2
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Pathiraja G, Yarbrough R, Rathnayake H. Fabrication of ultrathin CuO nanowires augmenting oriented attachment crystal growth directed self-assembly of Cu(OH) 2 colloidal nanocrystals. NANOSCALE ADVANCES 2020; 2:2897-2906. [PMID: 36132408 PMCID: PMC9419473 DOI: 10.1039/d0na00308e] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 05/18/2020] [Indexed: 05/12/2023]
Abstract
Augmenting the oriented attachment (OA) crystal growth phenomena, the fabrication of ultrathin CuO nanowires is demonstrated from self-assembled one-dimensional (1D) nanowires of Cu(OH)2 nanocrystals for the first time.
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Affiliation(s)
- Gayani Pathiraja
- Department of Nanoscience
- Joint School of Nanoscience and Nanoengineering
- University of North Carolina at Greensboro
- Greensboro
- USA
| | - Ryan Yarbrough
- Department of Nanoscience
- Joint School of Nanoscience and Nanoengineering
- University of North Carolina at Greensboro
- Greensboro
- USA
| | - Hemali Rathnayake
- Department of Nanoscience
- Joint School of Nanoscience and Nanoengineering
- University of North Carolina at Greensboro
- Greensboro
- USA
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Davis K, Yarbrough R, Froeschle M, White J, Rathnayake H. Band gap engineered zinc oxide nanostructures via a sol-gel synthesis of solvent driven shape-controlled crystal growth. RSC Adv 2019; 9:14638-14648. [PMID: 35516315 PMCID: PMC9064155 DOI: 10.1039/c9ra02091h] [Citation(s) in RCA: 84] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Accepted: 04/29/2019] [Indexed: 11/26/2022] Open
Abstract
A reliable sol-gel approach, which combines the formation of ZnO nanocrystals and a solvent driven, shape-controlled, crystal-growth process to form well-organized ZnO nanostructures at low temperature is presented. The sol of ZnO nanocrystals showed shape-controlled crystal growth with respect to the solvent type, resulting in either nanorods, nanoparticles, or nanoslates. The solvothermal process, along with the solvent polarity facilitate the shape-controlled crystal growth process, augmenting the concept of a selective adhesion of solvents onto crystal facets and controlling the final shape of the nanostructures. The XRD traces and XPS spectra support the concept of selective adhesion of solvents onto crystal facets that leads to yield different ZnO morphologies. The shift in optical absorption maxima from 332 nm in initial precursor solution, to 347 nm for ZnO nanocrystals sol, and finally to 375 nm for ZnO nanorods, evidenced the gradual growth and ripening of nanocrystals to dimensional nanostructures. The engineered optical band gaps of ZnO nanostructures are found to be ranged from 3.10 eV to 3.37 eV with respect to the ZnO nanostructures formed in different solvent systems. The theoretical band gaps computed from the experimental XRD spectral traces lie within the range of the optical band gaps obtained from UV-visible spectra of ZnO nanostructures. The spin-casted thin film of ZnO nanorods prepared in DMF exhibits the electrical conductivity of 1.14 × 10-3 S cm-1, which is nearly one order of magnitude higher than the electrical conductivity of ZnO nanoparticles formed in hydroquinone and ZnO sols. The possibility of engineering the band gap and electrical properties of ZnO at nanoscale utilizing an aqueous-based wet chemical synthesis process presented here is simple, versatile, and environmentally friendly, and thus may applicable for making other types of band-gap engineered metal oxide nanostructures with shape-controlled morphologies and optoelectrical properties.
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Affiliation(s)
- Klinton Davis
- Department of Nanoscience, Joint School of Nanoscience & Nanoengineering, University of North Carolina at Greensboro Greensboro NC 27401 USA +1-336-285-2860
| | - Ryan Yarbrough
- Department of Nanoscience, Joint School of Nanoscience & Nanoengineering, University of North Carolina at Greensboro Greensboro NC 27401 USA +1-336-285-2860
| | - Michael Froeschle
- Department of Nanoscience, Joint School of Nanoscience & Nanoengineering, University of North Carolina at Greensboro Greensboro NC 27401 USA +1-336-285-2860
| | - Jamel White
- Department of Nanoscience, Joint School of Nanoscience & Nanoengineering, University of North Carolina at Greensboro Greensboro NC 27401 USA +1-336-285-2860
| | - Hemali Rathnayake
- Department of Nanoscience, Joint School of Nanoscience & Nanoengineering, University of North Carolina at Greensboro Greensboro NC 27401 USA +1-336-285-2860
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Zhang X, Liu S, Wu F, Peng X, Yang B, Xiang Y. Phase-Selective Synthesis of CIGS Nanoparticles with Metastable Phases Through Tuning Solvent Composition. NANOSCALE RESEARCH LETTERS 2018; 13:362. [PMID: 30430270 PMCID: PMC6235770 DOI: 10.1186/s11671-018-2781-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Accepted: 10/31/2018] [Indexed: 05/15/2023]
Abstract
I-III-VI2 compounds have shown great interests in the application of functional semiconductors. Among them, Cu(In,Ga)S2 has been a promising candidate due to its excellent optoelectronic properties. Although the polymorphs of Cu(In,Ga)S2 have been attracted extensive attentions, the efforts to developing the methodologies for phase-controlled synthesis of them are rare. In this paper, we reported a phase-selective synthesis of CIGS nanoparticles with metastable phases via simply changing the composition of solvents. For the wet chemistry synthesis, the microstructure of the initial nuclei is decisive to the crystal structure of final products. In the formation of Cu(In,Ga)S2, the solvent environment is the key factor, which could affect the coordination of monomers and influence the thermodynamic conditions of Cu-S nucleation. Moreover, wurtzite and zincblende Cu(In,Ga)S2 nanoparticles are selectively prepared by choosing pure en or its mixture with deionized water as reaction solvent. The as-synthesized wurtzite Cu(In,Ga)S2 possess a band gap of 1.6 eV and a carrier mobility of 4.85 cm2/Vs, which indicates its potential to construct a heterojunction with hexagonal-structured CdS for solar cells.
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Affiliation(s)
- Xiaokun Zhang
- School of Materials and Energy, University of Electronic Science and Technology of China, 2006 Xiyuan Avenue, West High-Tech Zone, Chengdu, 611731 Sichuan China
| | - Shuai Liu
- School of Materials and Energy, University of Electronic Science and Technology of China, 2006 Xiyuan Avenue, West High-Tech Zone, Chengdu, 611731 Sichuan China
| | - Fang Wu
- School of Materials and Energy, University of Electronic Science and Technology of China, 2006 Xiyuan Avenue, West High-Tech Zone, Chengdu, 611731 Sichuan China
| | - Xiaoli Peng
- School of Materials and Energy, University of Electronic Science and Technology of China, 2006 Xiyuan Avenue, West High-Tech Zone, Chengdu, 611731 Sichuan China
| | - Baoguo Yang
- Science and Technology on Electronic Test and Measurement Laboratory, The 41st Research Institute of CETC, Qingdao, 266555 Shandong China
| | - Yong Xiang
- School of Materials and Energy, University of Electronic Science and Technology of China, 2006 Xiyuan Avenue, West High-Tech Zone, Chengdu, 611731 Sichuan China
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Mukherjee J, Gupta MN. Protein aggregates: Forms, functions and applications. Int J Biol Macromol 2017; 97:778-789. [DOI: 10.1016/j.ijbiomac.2016.11.014] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2015] [Revised: 11/02/2016] [Accepted: 11/05/2016] [Indexed: 11/15/2022]
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Fichtner A, Jalil A, Pyell U. Determination of the Exact Particle Radius Distribution for Silica Nanoparticles via Capillary Electrophoresis and Modeling the Electrophoretic Mobility with a Modified Analytic Approximation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:2325-2339. [PMID: 28194970 DOI: 10.1021/acs.langmuir.6b04543] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
In this study, we use aqueous dispersions of amorphous silica nanoparticles of various sizes to investigate whether electropherograms recorded from capillary electrophoresis experiments can be converted directly into exact number-based particle radius distributions, provided that there is a relaxation effect-based size selectivity of the electrophoretic mobility and provided that the electrokinetic potential ζ of the particles can be regarded to be homogeneous over the surface of the particles, independent of the particle size. The results of this conversion procedure are compared with number-based particle radius distributions obtained from a large set of transmission electron microscopy (TEM) data. For this specific example, it is shown that the modified analytic approximation developed by Ohshima adequately describes the mobility-dependent relaxation effect and the electrophoretic mobility of the particle as a function of the reduced hydrodynamic radius and electrokinetic potential, which is a prerequisite for the presented procedure. Simultaneously, we confirmed that for the given Debye length/particle diameter ratio the electrokinetic surface charge density can be regarded to be size-invariant (including spherical geometry and planar limiting case). It is shown that the accuracy of the results of the developed method is comparable to that gained by a large set of TEM data, which is important when a precise description of the particle size distribution is needed to deduce conclusions regarding the underlying mechanism(s) of particle growth. The values obtained for the dispersion (width) of the distribution show only a small negative deviation, when compared with the TEM data (4-16%).
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Affiliation(s)
- Anna Fichtner
- Department of Chemistry, University of Marburg , Hans-Meerwein-Straße, D-35032 Marburg, Germany
| | - Alaa Jalil
- Department of Chemistry, University of Marburg , Hans-Meerwein-Straße, D-35032 Marburg, Germany
| | - Ute Pyell
- Department of Chemistry, University of Marburg , Hans-Meerwein-Straße, D-35032 Marburg, Germany
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Ma X, Wen X, Toh YR, Huang KY, Tang J, Yu P. Dynamic study on the transformation process of gold nanoclusters. NANOTECHNOLOGY 2014; 25:445705. [PMID: 25319841 DOI: 10.1088/0957-4484/25/44/445705] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In this paper, the transformation process from Au8 to Au25 nanoclusters (NCs) is investigated with steady state fluorescence spectroscopy and time-resolved fluorescence spectroscopy at various reaction temperatures and solvent diffusivities. Results demonstrate that Au8 NCs, protected by bovine serum albumin, transform into Au25 NCs under controlled pH values through an endothermic reaction with the activation energy of 74 kJ mol(-1). Meanwhile, the characteristic s-shaped curves describing the formation of Au25 NCs suggest this process involves a diffusion controlled growth mechanism.
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Affiliation(s)
- Xiaoqian Ma
- Research Centre for Applied Science, Academia Sinica, Taipei, Taiwan
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Sabir TS, Rowland L, Milligan JR, Yan D, Aruni AW, Chen Q, Boskovic DS, Kurti RS, Perry CC. Mechanistic investigation of seeded growth in triblock copolymer stabilized gold nanoparticles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:3903-3911. [PMID: 23473268 PMCID: PMC4440571 DOI: 10.1021/la400387h] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We report the seeded synthesis of gold nanoparticles (GNPs) via the reduction of HAuCl4 by (L31 and F68) triblock copolymer (TBP) mixtures. In the present study, we focused on [TBP]/[Au(III)] ratios of 1-5 (≈1 mM HAuCl4) and seed sizes ~20 nm. Under these conditions, the GNP growth rate is dominated by both the TBP and seed concentrations. With seeding, the final GNP size distributions are bimodal. Increasing the seed concentration (up to ~0.1 nM) decreases the mean particle sizes 10-fold, from ~1000 to 100 nm. The particles in the bimodal distribution are formed by the competitive direct growth in solution and the aggregative growth on the seeds. By monitoring kinetics of GNP growth, we propose that (1) the surface of the GNP seeds embedded in the TBP cavities form catalytic centers for GNP growth and (2) large GNPs are formed by the aggregation of GNP seeds in an autocatalytic growth process.
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Affiliation(s)
- Theodore S. Sabir
- Department of Basic Sciences, School of Medicine, Loma Linda University, Loma Linda, CA 92350
| | - Leah Rowland
- Department of Basic Sciences, School of Medicine, Loma Linda University, Loma Linda, CA 92350
| | - Jamie R. Milligan
- Department of Radiology, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093
| | - Dong Yan
- Center for Nanoscale Science and Engineering, University of California, Riverside, 900 University Avenue, Riverside, CA 92521
| | - A. Wilson Aruni
- Department of Basic Sciences, School of Medicine, Loma Linda University, Loma Linda, CA 92350
| | - Qiao Chen
- Department of Chemistry, School of Life Sciences, University of Sussex, Brighton BN1 9QJ, United Kingdom
| | - Danilo S. Boskovic
- Department of Basic Sciences, School of Medicine, Loma Linda University, Loma Linda, CA 92350
| | - R. Steven Kurti
- School of Dentistry, Loma Linda University, Loma Linda, CA 92350
| | - Christopher C. Perry
- Department of Basic Sciences, School of Medicine, Loma Linda University, Loma Linda, CA 92350
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Celebi K, Cole MT, Choi JW, Wyczisk F, Legagneux P, Rupesinghe N, Robertson J, Teo KBK, Park HG. Evolutionary kinetics of graphene formation on copper. NANO LETTERS 2013; 13:967-74. [PMID: 23339597 DOI: 10.1021/nl303934v] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
It has been claimed that graphene growth on copper by chemical vapor deposition is dominated by crystallization from the surface initially supersaturated with carbon adatoms, which implies that the growth is independent of hydrocarbon addition after the nucleation phase. Here, we present an alternative growth model based on our observations that oppose this claim. Our Gompertzian sigmoidal growth kinetics and secondary nucleation behavior support the postulate that the growth can be controlled by adsorption-desorption dynamics and the dispersive kinetic processes of catalytic dissociation and dehydrogenation of carbon precursors on copper.
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Affiliation(s)
- Kemal Celebi
- Institute of Energy Technology, ETH Zürich, Zürich CH-8092, Switzerland
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Mahynski NA, Irick B, Panagiotopoulos AZ. Structure of phase-separated athermal colloid-polymer systems in the protein limit. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2013; 87:022309. [PMID: 23496518 DOI: 10.1103/physreve.87.022309] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2013] [Indexed: 06/01/2023]
Abstract
Structural features of phase-separated athermal colloid-polymer mixtures in the so-called "protein limit," where polymer chain dimensions exceed those of the colloid, are investigated using grand canonical Monte Carlo simulations on a fine lattice. Previous work [N. A. Mahynski et al., Phys. Rev. E 85, 051402 (2012)] has shown that this model accurately captures the phase behavior of experimental systems, and that colloids with sufficiently small diameters, σ(c), relative to that of the monomeric segments, σ(s), phase separate more readily than their large-diameter counterparts. In the present study, we directly connect colloid and polymer structure with their phase behavior by investigating these solutions along their binodal curves; we also explore the role of colloid surface curvature in destabilizing such solutions. Our findings suggest that simple consideration of an additional depletion radius, on the order of the σ(s), leads to a quantitatively accurate prediction of the division between stable and unstable ranges of d=σ(s)/σ(c). We compare these results to continuum models with different bonding potentials between monomer segments in order to elucidate the significance of the lattice model's bond fluctuations and inherently coarse colloid surface. In a number of cases, the continuum models deviate both qualitatively and quantitatively from the lattice results, but the binodals of the continuum models are presently not known, making a strong conclusion about these differences impossible.
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Affiliation(s)
- Nathan A Mahynski
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08540, USA
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Malhotra D, Mukherjee J, Gupta MN. Post-ultrasonic irradiation time is important in initiating citrate-coated α-Fe2O3 nanorod formation. RSC Adv 2013. [DOI: 10.1039/c3ra41593g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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12
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Jiang F, Muscat AJ. Ligand-controlled growth of ZnSe quantum dots in water during Ostwald ripening. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:12931-12940. [PMID: 22881121 DOI: 10.1021/la301186n] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
A strong ligand effect was observed for the aqueous-phase growth of ZnSe quantum dots (QDs) in the Ostwald ripening (OR) stage. The QDs were made by injecting Se monomer at room temperature followed by a ramp to 100 °C. The ramp produced a second, more gradual increase in the concentrations of both Zn and Se monomers fed by the dissolution of QDs below the critical size. The dissolution process was followed using measurements of the mass of Zn in QDs and in the supernatant by inductively coupled plasma optical emission spectroscopy (ICP-OES). Despite the flux of monomers, there was little growth in the QDs of average size based on UV-vis absorption spectra, until the temperature reached 100 °C, when there was a period of rapid growth followed by a period of linear growth. The linear growth stage is the result of OR as the total mass of Zn in QDs and in the solvent remained constant. The growth data were fit to a continuum model for the limiting case of surface reaction control. The rate is proportional to the equilibrium coefficient for ligand detachment from the QD surface. The ligand 3-mercaptopropionic acid (MPA) was the most tightly bound to the surface and produced the lowest growth rate of (1.5-2) × 10(-3) nm/min in the OR stage, whereas thiolactic acid (TLA) was the most labile and produced the highest growth rate of 3 × 10(-3) nm/min. Methyl thioglycolate (MTG) and thioglycolic acid (TGA) produced rates in between these values. Ligands containing electron-withdrawing groups closer to the S atom and branching promote growth, whereas longer, possibly bidendate, ligands retard it. Mixed ligand experiments confirmed that growth is determined by ligand bonding strength to the QD. Photoluminescence spectroscopy showed that the more labile the ligand, the more facile the repair of surface defects during the exposure of the QDs to room light.
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Affiliation(s)
- Feng Jiang
- Department of Chemical and Environmental Engineering, University of Arizona, Tucson, Arizona 85721, United States
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