Light/Electricity Energy Conversion and Storage for a Hierarchical Porous In₂S₃@CNT/SS Cathode towards a Flexible Li‐CO₂ Battery

Abstract

Ap hotoinduced flexible Li-CO 2 battery with welldesigned, hierarchical porous,a nd free-standing In 2 S 3 @CNT/ SS (ICS) as abifunctional photoelectrode to accelerate both the CO 2 reduction and evolution reactions (CDRR and CDER) is presented. The photoinduced Li-CO 2 battery achieved ar ecord-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 around trip efficiency of 98.1 %, which is the highest value ever reported (< 80 %) so far.T hese excellent properties can be ascribed to the hierarchical porous and freestanding structure of ICS,a sw ell as the key role of photogenerated electrons and holes during discharging and charging processes.Amechanism 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.

Review—Li-Ion Photo-Batteries: Challenges and Opportunities

“…Furthermore, the use of TiO 2 /perovskite layers 17 between an FTO current collector and a dense carbon-sulfur cathode in a standard Li-S battery may result in a reduction in the charge time with respect to a standard power supply charge. 23 In 2020 Guan et al prepared In 2 S 3 @CNT on stainless steel foam as photocathode for photo assisted charged Li-CO 2 batteries showing an increment of voltage discharge (from 2.73 V to 3.14 V) and decrement of voltage charge (from 3.86 V to 3.20 V) under light illumination. Monovalent In + was identified as transient mediator of CO 2 reduction at In 2 S 3 @CNT's surface: after its formation due to photoelectrons reduction, it an adduct of In 3+ and oxalate was formed.…”