Modulation of magnetic and electric fields for high-performance photo-assisted LiO2 batteries

Suppressing the rapid recombination of photogenerated carriers is crucial for enhancing the cycling stability of photo-assisted Li O 2 cells. Herein, a magnetic-electric field coupling-aided mechanism is presented to further retard the recombination of photogenerated electrons and holes. This mechanism involves the construction of a ZnO-NiO p-n heterojunction as a semiconductor catalyst, where the intrinsic electric field drives the directional migration of photoinduced electron-hole pairs toward the surfaces of ZnO and NiO, respectively, thereby achieving spatial separation of the carriers. Furthermore, an external magnetic field is applied to exert opposite Lorentz forces on the migrating electrons and holes, effectively suppressing their recombination. Electrons and holes can respectively effectively facilitate the creation and decomposition of Li 2 O 2 , enhancing the reaction kinetic performance of ORR and OER. The photo-assisted LOBs based on ZnO-NiO is enabled to exhibit an overpotential of 0.29 V under a magnetic field, with its cycle life increased by 147.67% compared with that of the battery without a magnetic field. This magneto-electric field coupling strategy offers valuable insights for the fields of photocatalysis and photo-assisted metal-air batteries.