Light/Electricity Energy Conversion and Storage for a Hierarchical Porous In2S3@CNT/SS Cathode towards a Flexible Li-CO2Battery

A photoinduced flexible Li-CO(2)battery with well-designed, hierarchical porous, and free-standing In2S3@CNT/SS (ICS) as a bifunctional photoelectrode to accelerate both the CO(2)reduction and evolution reactions (CDRR and CDER) is presented. The photoinduced Li-CO(2)battery achieved a record-high discharge voltage of 3.14 V, surpassing the thermodynamic limit of 2.80 V, and an ultra-low charge voltage of 3.20 V, achieving a round trip efficiency of 98.1 %, which is the highest value ever reported (<80 %) so far. These excellent properties can be ascribed to the hierarchical porous and free-standing structure of ICS, as well as the key role of photogenerated electrons and holes during discharging and charging processes. A mechanism is proposed for pre-activating CO(2)by reducing In(3+)to In(+)under light illumination. The mechanism of the bifunctional light-assisted process provides insight into photoinduced Li-CO(2)batteries and contributes to resolving the major setbacks of the system.