Boosting Cycling Stability and Rate Capability of Li–CO2Batteries via Synergistic Photoelectric Effect and Plasmonic Interaction

Abstract Sluggish CO 2 reduction/evolution kinetics at cathodes seriously impede the realistic applications of Li–CO 2 batteries. Herein, synergistic photoelectric effect and plasmonic interaction are introduced to accelerate CO 2 reduction/evolution reactions by designing a silver nanoparticle‐decorated titanium dioxide nanotube array cathode. The incident light excites energetic photoelectrons/holes in titanium dioxide to overcome reaction barriers, and induces the intensified electric field around silver nanoparticles to enable effective separation/transfer of photogenerated carriers and a thermodynamically favorable reaction pathway. The resulting Li–CO 2 battery demonstrates ultra‐low charge voltage of 2.86 V at 0.10 mA cm −2 , good cycling stability with 86.9 % round‐trip efficiency after 100 cycles, and high rate capability at 2.0 mA cm −2 . This work offers guidance on rational cathode design for advanced Li–CO 2 batteries and beyond.