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Rechargeable zinc-ion batteries (RZIBs) are mostly powered by aqueous electrolytes. However, uncontrolled water interactions often confer a small voltage window and poor battery capacity retention. Here, we explore replacing water with ethylene glycol as the primary solvent in zinc electrolyte formulations. The assembled batteries reveal suppressed electrolyte-induced parasitic reactions, leading to (1) expanded voltage stability windows up to 2.2 V, (2) prolonged zinc stripping/plating stability up to 2.4 times longer compared to the water-based counterparts, and (3) doubled cathode capacity retentions as observed in full-cell Zn-FeVO 4 RZIBs. Using a combination of synchrotron EXAFS and FTIR, we investigate the molecular level salt-solvent interactions and explain how the chelation ability of EG ligands reduces parasitic reactions to enable the enhanced electrochemical performances. The structural insights should provide guidelines on the selection of salt, concentration, and chelating solvents for robust multivalent-ion battery systems.

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Mg scrap is notorious for the high cost and serious pollution of its recycling process due to the good wettability and similar density of Mg melt to its solid inclusions. To support the sustainable growth of Mg industry and application, intensive effort has been contributed to the development high efficiency, flux-free purification techniques for Mg scrap recycling. In the present study, the purification of Mg scrap melt via filtration was theoretically analyzed by multi-phase fluid hydrodynamics. The relationships between the nozzle size in the filtration medium, melt penetrating-through speed and other filtration parameters were formulated. To provide a guideline to filtration engineering, the influence of processing parameters on the filtering efficiency were discussed.

The effects of metal depositions on pyrolyzed photoresist films (PPF) grown on silicon substrates were investigated. A silicon chip, spin-coated with a positive photoresist was pyrolyzed through heating to form a PPF, or a conductive carbon film. For increasing periods of time, nanometersized metal particles of platinum and palladium were spontaneously deposited on conductive carbon films by immersion in solutions of 0.049% HF containing 100 ppm, 200 ppm, and 500 ppm concentrations of metal ions Pt2+ or Pd2+. Following each hour of deposition, the electrochemical behavior of the metal-deposited carbon films were investigated by cyclic voltammetry, utilizing a 0.1 M H2SO4 electrolyte system. The electron-transfer rates and characteristics of hydrogen evolution exhibited positive catalytic effects when the platinum and palladium nanoparticles were deposited on the carbon films. Scanning electron microscopy and energy-dispersive x-ray analysis were employed to characterize the surface morphology and distribution of metal nanoparticles on the PPF surface based on metal ion concentration and deposition time. The depositions of metal nanoparticles accelerate the electron transfer process, which could improve the efficiency and performance of PPF electrodes in the production of hydrogen fuel.