Chalcogel represents a unique class of meso‐ to macroporous nanomaterials that offer applications in energy and environmental pursuits. Here, the synthesis of an ion‐exchangeable amorphous chalcogel using a nominal composition of K2CoMo2S10(KCMS) at room temperature is reported. Synchrotron X‐ray pair distribution function (PDF), X‐ray absorption near‐edge structure (XANES), and extended X‐ray absorption fine structure (EXAFS) reveal a plausible local structure of KCMS gel consisting of Mo5+2and Mo4+3clusters in the vicinity of di/polysulfides which are covalently linked by Co2+ions. The ionically bound K+ions remain in the percolating pores of the Co–Mo–S covalent network. XANES of Co K‐edge shows multiple electronic transitions, including quadrupole (1s→3d), shakedown (1s→4p + MLCT), and dipole allowed 1s→4p transitions. Remarkably, despite a lack of regular channels as in some crystalline solids, the amorphous KCMS gel shows ion‐exchange properties with UO22+ions. Additionally, it also presents surface sorption via [S∙∙∙∙UO22+] covalent interactions. Overall, this study underscores the synthesis of quaternary chalcogels incorporating alkali metals and their potential to advance separation science for cations and oxo‐cationic species by integrating a synergy of surface sorption and ion‐exchange.
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This paper reports a systematic study on the electrodeposition of metallic molybdenum from water-in-salt electrolytes containing superhigh concentrations of acetate. Cyclic voltammetry and DC deposition were carried out on rotating disk electrodes with various concentrations of CH3COOK and CH3COONH4to determine the effects of NH4+and K+on Mo deposition. A comparison was performed between CH3COOLi, CH3COONa, and CH3COOK to study the effects of different alkali metal cations. A synergistic effect was observed between K+and NH4+, where Mo deposition rate is enhanced in the presence of both cations. However, such synergistic effect was not observed between NH4+and other alkali cations. In addition, the impact of substrate on Mo deposition was also studied using Pt and Cu electrodes with different activity toward hydrogen evolution reaction. Electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy were used to characterize the surface morphology, crystallographic structure, and metallic state of Mo in the electrodeposited films.
more » « less- Award ID(s):
- 1941820
- PAR ID:
- 10517986
- Publisher / Repository:
- The Electrochemical Society
- Date Published:
- Journal Name:
- Journal of The Electrochemical Society
- Volume:
- 171
- Issue:
- 6
- ISSN:
- 0013-4651
- Page Range / eLocation ID:
- 062510
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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