Ag doped ZnO hollow nanosphere as a photocatalyst for enhanced performance in photo-assisted Li-O2 batteries

Photo-assisted electrochemical strategy has garnered interest for its ability to diminish the large overpotential of lithium-oxygen batteries (LOBs). Nonetheless, creating a sophisticated photocatalyst capable of absorbing a wide spectrum of light and dramatically lowering the recombination rate for electron-hole pairs presents a significant challenge. Herein, we design an Ag-doped ZnO (Ag@ZnO) hollow nanosphere as photocatalysts to boost the reaction dynamics of photo-assisted LOBs. The Ag@ZnO hollow nanospheres, featuring a mesoporous structure, are beneficial for improving O2 transport and enabling the retention of discharge products. Additionally, the ability to absorb light and the efficiencies of electron-hole separation are enhanced for Ag@ZnO as a result of Ag doping. The electrons generated by photoexcitation facilitate the conversion of O2 to produce Li2O2 during discharge, whereas during charging, the presence of holes causes the decomposition of Li2O2. Consequently, a significantly low overpotential of 0.22 V, ultrahigh cycling efficiency of 93.73%, and good reversibility was achieved for the photo-assisted LOBs using Ag@ZnO. We consider that this work can offer a reliable strategy to improve electrochemical kinetics and contribute to the development of efficient photocatalysts for photo-assisted LOBs.