Powering the Future: Unleashing the Potential of MXene‐Based Dual‐Functional Photoactive Cathodes in Photo‐Rechargeable Zinc‐Ion Capacitor

Abstract Dual‐functional photo‐rechargeable (photo‐R) energy storage devices, which acquire stored energy from solar energy harvesting, are being developed to battle the current energy crisis. In this study, these findings on the photo‐driven characteristics of MXene‐based photocathodes in photo‐R zinc‐ion capacitors (ZICs) are presented. Along with the pristine Ti 3 C 2 T x MXene, tellurium/Ti 3 C 2 T x (Te/Ti 3 C 2 T x ) hybrid nanostructure is synthesized via facile chemical vapor transport technique to examine them for photocathodes in ZICs. Interestingly, the evaluated self‐powered photodetector devices using MXene‐based samples revealed a pyro‐phototronic behavior introduced into the samples, with higher desirability observed in Te/Ti 3 C 2 T x . The photo‐R ZICs results exhibited a capacitance enhancement of 50.86% for Te/Ti 3 C 2 T x at two scan rates of 5 and 10 mV s −1 under illumination, compared to dark conditions. In contrast, a capacitance enhancement of 30.20% is obtained for the pristine Ti 3 C 2 T x at only a 5 mV s −1 scan rate. Furthermore, both samples achieved photo‐charging voltage responses of ≈960 mV, and photoconversion efficiencies of 0.01% (for Te/ Ti 3 C 2 T x ) and 0.07% (for Ti 3 C 2 T x ). These characteristics in MXene‐based single photo‐R ZICs are significant and considerable with the distinguished integrated photo‐R supercapacitors with solar cells, or coupled energy‐harvesting and energy‐storing devices reported recently in the literature.