Aqueous batteries (ABs) have attracted increasing attention because of their inherent safety and low cost. Nevertheless, hydrogen evolution reaction (HER) at the anode presents severe challenges for stable and safe operation of ABs. Instead of passivating the anode surface to hinder HER kinetics, a novel design strategy is proposed here to suppress the HER via alternating its thermodynamics pathway. By adding a hydrogen bond acceptor, dimethyl sulfoxide (DMSO), the onset potential of HER can be delayed by as much as 1.0 V (on titanium mesh). Spectral characterization and molecular dynamics simulation confirm that the formation of hydrogen bonds between DMSO and water molecules can reduce the water activity, thereby suppressing the HER. This strategy has proven to be universal in expanding the electrochemical window of aqueous electrolytes. For instance, unconventional V 2+ ↔V 3+ redox processes in Na 3 V 2 (PO 4 ) 3 (-1.2 V versus Ag/AgCl) and highly stable Zn plating/stripping processes can be realized in ABs.

Well-distributed graphene sheets doped with nitrogen (NGS) were prepared via a thermal annealing strategy with the existence of cyanamide. The cyanamide can efficiently restrain the conglomeration of the resultant graphene sheets and synchronously make sure the doping of nitrogen. Followed by the next-step of low-temperature solvothermal route, uniform ultrasmall tin sulfide (SnS 2 ) nanocrystals were readily grown on the preformed NGS (denoted as SnS 2 -NGS).Benefiting from the synergistic function between NGS and SnS 2 , the resultant composites exhibit excellent electrochemical performance. In case of estimation as anode materials for lithium-ion batteries (LIBs), SnS 2 -NGS with moderate weight ratio of SnS 2 deliver outstanding electrochemical outcomes giving the high reversible capacity of 1407 mA h g -1 at 200 mA g -1 after 120 cycles. The composites can also maintain a reversible capacity of about 200 mA h g -1 at a high current density of 10 A g -1 . The lithium-ion storage ability of prepared SnS 2 -NGS electrode is at the top rank in comparison with the other works. The obtained composites also achieve good sodium storage ability.

Due to the merits of low cost, safety, environmental friendliness, and abundant sodium reserves, non-aqueous and aqueous sodium-ion batteries are wonderful alternatives for large-scale energy storage.

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A novel aqueous sodium–manganese battery system with a long life span of over 7000 cycles.

Aqueous batteries (ABs) have attracted increasing attention because of their inherent safety and low cost. Nevertheless, hydrogen evolution reaction (HER) at the anode presents severe challenges for stable and safe operation of ABs. Instead of passivating the anode surface to hinder HER kinetics, a novel design strategy is proposed here to suppress the HER via alternating its thermodynamics pathway. By adding a hydrogen bond acceptor, dimethyl sulfoxide (DMSO), the onset potential of HER can be delayed by as much as 1.0 V (on titanium mesh). Spectral characterization and molecular dynamics simulation confirm that the formation of hydrogen bonds between DMSO and water molecules can reduce the water activity, thereby suppressing the HER. This strategy has proven to be universal in expanding the electrochemical window of aqueous electrolytes. For instance, unconventional V2+↔V3+ redox processes in Na3V2(PO4)3 (-1.2 V versus Ag/AgCl) and highly stable Zn plating/stripping processes can be realized in ABs.