We report an aqueous Zn−V 2 O 5 battery chemistry employing commercial V 2 O 5 cathode, Zn anode, and 3 M Zn(CF 3 SO 3 ) 2 electrolyte. We elucidate the Zn-storage mechanism in the V 2 O 5 cathode to be that hydrated Zn 2+ can reversibly (de)intercalate through the layered structure. The function of the cointercalated H 2 O is revealed to be shielding the electrostatic interactions between Zn 2+ and the host framework, accounting for the enhanced kinetics. In addition, the pristine bulk V 2 O 5 gradually evolves into porous nanosheets upon cycling, providing more active sites for Zn 2+ storage and thus rendering an initial capacity increase. As a consequence, a reversible capacity of 470 mAh g −1 at 0.2 A g −1 and a long-term cyclability with 91.1% capacity rentention over 4000 cycles at 5 A g −1 are achieved. The combination of the good battery performance, safety, scalable materials synthesis, and facile cell assembly indicates this aqueous Zn−V 2 O 5 system is promising for stationary grid storage applications.

A Zr and polyethylene glycol 800 [PEG(800)] modified Ni−B [Ni−Zr−B−PEG( 800)] amorphous alloy catalyst showed excellent catalytic performance, comparable to noble metal catalysts, in the chemoselective hydrogenation of benzoic acid to cyclohexane carboxylic acid. The synergistic effect between Zr and PEG( 800) is suggested to decrease significantly the agglomeration of the active Ni species, causing the Ni−Zr−B−PEG(800) to have a larger BET area, smaller particle size, and the greatest number of Ni active centers, accounting for its high activity in water. The solvent effect on the selectivity was studied in detail. The high polarity of the water favors the orientation of carboxyl group toward the solvent, resulting in the selective hydrogenation of the aromatic ring, thus leading to a high selectivity for production of cyclohexane carboxylic acid compared to that occurring in the low polarity cyclohexane.

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Metallic antimony (Sb) is an attractive anode material for lithium-/sodiumion batteries (LIBs/SIBs) because of its high theoretical capacity (660 mA h g −1 ), but it suffers from poor cycling performance caused by the huge volume expansion and the unstable solid electrolyte interphase (SEI). Here, we report a high-performing microsized Sb anode for both LIBs and SIBs by coupling it with fluoroethylene carbonate (FEC) containing electrolytes. The optimum amount of FEC (10 vol %) renders a stable LiF/ NaF-rich SEI on Sb electrodes that can suppress the continuous electrolyte decomposition and accommodate the volume variation. The microsized Sb electrode gradually evolves into a porous integrity assembled by nanoparticles in FEC-containing electrolytes during cycling, which is totally different from that in the FEC-free counterpart. As a result, the microsized Sb electrodes exhibit a reversible capacity of 540 mA h g −1 with 85.3% capacity retention after 150 cycles at 1000 mA g −1 for LIBs and 605 mA h g −1 with 95.4% capacity retention after 150 cycles at 200 mA g −1 for SIBs. More impressively, the prototype full Li-based (i.e., Sb/LiNi 0.8 Co 0.1 Mn 0.1 O 2 cell) and Na-based (i.e., Sb/Na 3 V 2 (PO 4 ) 2 O 2 F cell) batteries also achieve good cycling durability. This facile strategy of electrolyte formulation to boost the cycling performance of microsized Sb anodes will provide a new avenue for developing stable alloying-type materials for both LIBs and SIBs.