1
|
Raciti D, Cockayne E, Vinson J, Schwarz K, Hight Walker AR, Moffat TP. SHINERS Study of Chloride Order-Disorder Phase Transition and Solvation of Cu(100). J Am Chem Soc 2024; 146:1588-1602. [PMID: 38170994 DOI: 10.1021/jacs.3c11812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Shell-isolated nanoparticle enhanced Raman spectroscopy (SHINERS) and density functional theory (DFT) are used to probe Cl- adsorption and the order-disorder phase transition associated with the c(2 × 2) Cl- adlayer on Cu(100) in acid media. A two-component ν(Cu-Cl) vibrational band centered near 260 ± 1 cm-1 is used to track the potential dependence of Cl- adsorption. The potential dependence of the dominant 260 cm-1 component tracks the coverage of the fluctional c(2 × 2) Cl- phase on terraces in good agreement with the normalized intensity of the c(2 × 2) superstructure rods in prior surface X-ray diffraction (SXRD) studies. As the c(2 × 2) Cl- coverage approaches saturation, a second ν(Cu-Cl) component mode emerges between 290 and 300 cm-1 that coincides with the onset and stiffening of step faceting where Cl- occupies the threefold hollow sites to stabilize the metal kink saturated Cu <100> step edge. The formation of the c(2 × 2) Cl- adlayer is accompanied by the strengthening of ν(O-H) stretching modes in the adjacent non-hydrogen-bonded water at 3600 cm-1 and an increase in hydronium concentration evident in the flanking H2O modes at 3100 cm-1. The polarization of the water molecules and enrichment of hydronium arise from the combination of Cl- anionic character and lateral templating provided by the c(2 × 2) adlayer, consistent with SXRD studies. At negative potentials, Cl- desorption occurs followed by development of a sulfate νs(S═O) band. Below -1.1 V vs Hg/HgSO4, a new 200 cm-1 mode emerges congruent with hydride formation and surface reconstruction reported in electrochemical scanning tunneling microscopy studies.
Collapse
Affiliation(s)
- David Raciti
- Material Measurement Laboratory, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, Maryland 20899, United States
| | - Eric Cockayne
- Material Measurement Laboratory, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, Maryland 20899, United States
| | - John Vinson
- Material Measurement Laboratory, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, Maryland 20899, United States
| | - Kathleen Schwarz
- Material Measurement Laboratory, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, Maryland 20899, United States
| | - Angela R Hight Walker
- Physical Measurement Laboratory, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, Maryland 20899, United States
| | - Thomas P Moffat
- Material Measurement Laboratory, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, Maryland 20899, United States
| |
Collapse
|
2
|
Hu Q, Zhao H, Ouyang S, Liang Y, Yang H, Zhu X. The water structure around chloride ion investigated from D2O ↔ H2O substitution effect. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.120702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
3
|
Lu H, Shi W, Zhang JH, Chen AC, Guan W, Lei C, Greer JR, Boriskina SV, Yu G. Tailoring the Desorption Behavior of Hygroscopic Gels for Atmospheric Water Harvesting in Arid Climates. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2205344. [PMID: 35901232 DOI: 10.1002/adma.202205344] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 07/11/2022] [Indexed: 06/15/2023]
Abstract
The ubiquitous nature of atmospheric moisture makes it a significant water resource available at any geographical location. Atmospheric water harvesting (AWH) technology, which extracts moisture from the ambient air to generate clean water, is a promising strategy to realize decentralized water production. The high water uptake by salt-based sorbents makes them attractive for AWH, especially in arid environments. However, they often have relatively high desorption heat, rendering water release an energy-intensive process. A LiCl-incorporating polyacrylamide hydrogel (PAM-LiCl) capable of effective moisture harvesting from arid environments is proposed. The interactions between the hydrophilic hydrogel network and the captured water generate more free and weakly bonded water, significantly lowering the desorption heat compared with conventional neat salt sorbents. Benefiting from the affinity for swelling of the polymer backbones, the developed PAM-LiCl achieves a high water uptake of ≈1.1 g g-1 at 20% RH with fast sorption kinetics of ≈0.008 g g-1 min-1 and further demonstrates a daily water yield up to ≈7 g g-1 at this condition. These findings provide a new pathway for the synthesis of materials with efficient water absorption/desorption properties, to reach energy-efficient water release for AWH in arid climates.
Collapse
Affiliation(s)
- Hengyi Lu
- Materials Science and Engineering Program and Walker Department of Mechanical Engineering, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Wen Shi
- Materials Science and Engineering Program and Walker Department of Mechanical Engineering, The University of Texas at Austin, Austin, TX, 78712, USA
| | - James H Zhang
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Amylynn C Chen
- Division of Engineering and Applied Science, California Institute of Technology, Pasadena, CA, 91125, USA
| | - Weixin Guan
- Materials Science and Engineering Program and Walker Department of Mechanical Engineering, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Chuxin Lei
- Materials Science and Engineering Program and Walker Department of Mechanical Engineering, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Julia R Greer
- Division of Engineering and Applied Science, California Institute of Technology, Pasadena, CA, 91125, USA
| | - Svetlana V Boriskina
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Guihua Yu
- Materials Science and Engineering Program and Walker Department of Mechanical Engineering, The University of Texas at Austin, Austin, TX, 78712, USA
| |
Collapse
|
4
|
Study on the Structure of a Mixed KCl and K 2SO 4 Aqueous Solution Using a Modified X-ray Scattering Device, Raman Spectroscopy, and Molecular Dynamics Simulation. Molecules 2022; 27:molecules27175575. [PMID: 36080342 PMCID: PMC9457528 DOI: 10.3390/molecules27175575] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 08/25/2022] [Accepted: 08/27/2022] [Indexed: 12/02/2022] Open
Abstract
The microstructure of a mixed KCl and K2SO4 aqueous solution was studied using X-ray scattering (XRS), Raman spectroscopy, and molecular dynamics simulation (MD). Reduced structure functions [F(Q)], reduced pair distribution functions [G(r)], Raman spectrum, and pair distribution functions (PDF) were obtained. The XRS results show that the main peak (r = 2.81 Å) of G(r) shifted to the right of the axis (r = 3.15 Å) with increased KCl and decreased K2SO4. The main peak was at r = 3.15 Å when the KCl concentration was 26.00% and the K2SO4 concentration was 0.00%. It is speculated that this phenomenon was caused by the main interaction changing, from K-OW (r = 2.80 Å) and OW-OW (r = 2.80 Å), to Cl−-OW (r = 3.14 Å) and K+-Cl− (r = 3.15 Å). According to the trend of the hydrogen bond structure in the Raman spectrum, when the concentration of KCl was high and K2SO4 was low, the destruction of the tetrahedral hydrogen bond network in the solution was more serious. This shows that the destruction strength of the anion to the hydrogen bond network structure in solution was Cl− > SO42−. In the MD simulations, the coordination number of OW-OW decreased with increasing KCl concentration, indicating that the tetrahedral hydrogen bond network was severely disrupted, which confirmed the results of the Raman spectroscopy. The hydration radius and coordination number of SO42− in the mixed solution were larger than Cl−, thus revealing the reason why the solubility of KCl in water was greater than that of K2SO4 at room temperature.
Collapse
|
5
|
Meng X, Li X, Zhang Q, Wu L, Cao F. Temperature-dependent structure of 3.5 wt.% NaCl aqueous solution: Theoretical and Raman investigation. J Mol Struct 2022. [DOI: 10.1016/j.molstruc.2021.132279] [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]
|
6
|
Li D, Zhu Z, Sun DW. Quantification of hydrogen bonding strength of water in saccharide aqueous solutions by confocal Raman microscopy. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.117498] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
|
7
|
Li D, Zhu Z, Sun DW. Visualization of the in situ distribution of contents and hydrogen bonding states of cellular level water in apple tissues by confocal Raman microscopy. Analyst 2020; 145:897-907. [PMID: 31820748 DOI: 10.1039/c9an01743g] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Raman spectroscopy has been employed for studying the hydrogen bonding states of water molecules for decades, however, Raman imaging data contain thousands of spectra, making it challenging to obtain information on water with different hydrogen bonds. In the current study, a novel method combining confocal Raman microscopy (CRM) imaging with the iterative curve fitting algorithms was developed to determine the distribution of water contents at the cellular level and water states with different hydrogen bonds in apple tissues. Raman imaging data ranging from 2700 to 3800 cm-1 were acquired from whole cells in the apple tissue, which were then decomposed into seven sub-peaks using the fixed-position Gaussian iterative curve fitting (FPGICF) algorithm. The content and hydrogen bonding states of cellular water were calculated as the area sum of the OH stretching vibration and the area ratio of DA-OH over DDAA-OH stretching vibration or the number of hydrogen bonds of each water molecule, respectively. Finally, the area of each sub-peak, the area sum of the OH stretching vibration, and the area ratio of DA-OH over DDAA-OH stretching vibration were used to visualize the distribution of each sub-peak, water contents and water states with different hydrogen bonds, respectively. In addition, it was found that the number of hydrogen bonds of each water molecule could also be considered as a criterion to describe the hydrogen bond states of water in apple tissues. The availability of such information should provide new insights for future study of cellular water in other food materials.
Collapse
Affiliation(s)
- Dongmei Li
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510641, China.
| | | | | |
Collapse
|
8
|
|
9
|
Sun CQ, Huang Y, Zhang X. Hydration of Hofmeister ions. Adv Colloid Interface Sci 2019; 268:1-24. [PMID: 30921543 DOI: 10.1016/j.cis.2019.03.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Revised: 03/04/2019] [Accepted: 03/07/2019] [Indexed: 01/08/2023]
Abstract
Water dissolves salt into ions and then hydrates the ions to form an aqueous solution. Hydration of ions deforms the hydrogen bonding network and triggers the solution with what the pure water never shows such as conductivity, molecular diffusivity, thermal stability, surface stress, solubility, and viscosity, having enormous impact to many branches in biochemistry, chemistry, physics, and energy and environmental industry sectors. However, regulations for the solute-solute-solvent interactions are still open for exploration. From the perspective of the screened ionic polarization and O:H-O bond relaxation, this treatise features the recent progress and a perspective in understanding the hydration dynamics of Hofmeister ions in the typical YI, NaX, ZX2, and NaT salt solutions (Y = Li, Na, K, Rb, Cs; X = F, Cl, Br, I; Z = Mg, Ca, Ba, Sr; T = ClO4, NO3, HSO4, SCN). Phonon spectrometric analysis turned out the f(C) number fraction of bonds transition from the mode of deionized water to the hydrating. The linear f(C) ∝ C form features the invariant hydration volume of small cations that are fully-screened by their hydration H2O dipoles. The nonlinear f(C) ∝ 1 - exp.(-C/C0) form describes that the number insufficiency of the ordered hydrating H2O dipoles partially screens the anions. Molecular anions show stronger yet shorter electric field of dipoles. The screened ionic polarization, inter-solute interaction, and O:H-O bond transition unify the solution conductivity, surface stress, viscosity, and critical energies for phase transition.
Collapse
|