Interfacial Molecule Engineering for Reversible Zn Electrochemistry

Theunstable Zn interface caused by undesired dendrites and parasiticside reactions greatly impedes the deployment of aqueous Zn metalbatteries. Herein, an efficient adsorptive additive strategy is proposedto reshape the electric double layer and regulate Zn interfacial chemistry.2-Hydroxy-4 & PRIME;-(2-hydroxyethoxy)-2-methylpropiophenone (Irgacure2959) was selected owing to its strong adsorption ability, intermolecularhydrogen bonding, and exposed strong electronegative carbonyl group.The constructed self-adaptive adlayer contributes to a localized H2O, SO4 (2-)-poor environment andhorizontal alignment of Zn deposits along the (002) plane, thus endowingthermodynamically stable and highly reversible Zn electrochemistry.As a result, reversible plating/stripping of 3800 h and high Coulombicefficiency of 99.8% are achieved. Intriguingly for practical application,the economical additive (0.016 USD L-1) enablesstable discharge output for 500 cycles in Zn/VS2 cellsat a low negative-to-positive capacity ratio of 2.5 (cathode massloading: 10.8 mg cm(-2)), holding great promise foruse in a scalable, low-cost, rechargeable battery.