A Photoelectronic‐Triggered Defect‐Induced Local Charge Separation Strategy for Promoting Bidirectional Sulfur Redox Kinetics in Lithium‐Sulfur Batteries

Photo-assisted strategies have demonstrated compelling prospects for addressing critical challenges of polysulfides shuttle and sluggish reaction kinetics in lithium-sulfur batteries (LSBs), but a spatial shielding effect is inevitable to impede bidirectional redox kinetics of polysulfides with conventional heterojunction photoelectrodes. Herein, a local charge separation strategy enhanced by photoelectronic effect is developed with titanium-vacancy defective TiO₂ (Tiv-TiO₂) photoelectrodes for enhancing surface potentials, promoting photogenerated electron/hole separation, and optimizing bidirectional sulfur redox kinetics in photo-assisted LSBs (PA-LSBs). Therefore, the chemical interactions of Tiv-TiO₂ with polysulfides are intensified, significantly lowering lithiation/delithiation energy barriers and mitigating the shuttle effect. The resulting PA-LSBs achieve an exceptional cyclability of a minimal capacity decay rate of 0.056% per cycle over 400 cycles at 2C under light irradiation. This work not only provides rational designs of high-adsorption and fast-kinetic catalysts in PA-LSBs, but also highlights the transformative potential of light-energy coupling in advancing next-generation energy storage technologies.