The physical crosslinking of polymeric binders through coordination chemistry significantly improves the electrochemical performance of silicon-based negative electrodes. Scanning electron microscopy coupled with energy dispersive X-ray spectroscopy is used to probe the nanoscale morphology of such electrodes. This technique reveals the homogeneous coordination of carboxylated binder with Zn cations and its layering on the silicon surface.
View Article and Find Full Text PDFThe role of the physicochemical properties of the water-soluble polyacrylic acid (PAA) binder in the electrochemical performance of highly loaded silicon/graphite 50/50 wt % negative electrodes has been examined as a function of the neutralization degree in PAAHLi at the initial cycle in an electrolyte not containing ethylene carbonate. Electrode processing in the acidic PAAH binder at pH 2.5 leads to a deep copper corrosion, resulting in a significant electrode cohesion and adhesion to the current collector surface, but the strong binder rigidity may explain the big cracks occurring on the electrode surface at the first cycle.
View Article and Find Full Text PDFNi, Cu, Cu(90)Ni(10) and Cu(70)Ni(30) were evaluated as cathode materials for the conversion of nitrate to nitrogen by a paired electrolysis process using an undivided flow-through electrolyzer. Firstly, corrosion measurements revealed that Ni and Cu(70)Ni(30) electrodes have a much better corrosion resistance than Cu and Cu(90)Ni(10) in the presence of chloride, nitrate and ammonia. Secondly, nitrate electroreduction experiments showed that the cupro-nickel electrodes are the most efficient for reducing nitrate to ammonia with a selectivity of 100%.
View Article and Find Full Text PDFIn this study, nitrate removal in alkaline media by a paired electrolysis with copper cathode and Ti/IrO(2) anode enabled the conversion of nitrate to nitrogen. Optimum conditions for carrying out reduction of nitrate to ammonia and subsequent oxidation of the produced ammonia to nitrogen were found. At the copper cathode, electroreduction of nitrate to ammonia was optimal near -1.
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