A Review on 2D Halide Perovskite for Supercapacitors Application

ABSTRACT Emerging as quite intriguing substances for energy storage devices, including solar cells, LEDs, capacitors, or supercapacitors are metal halide perovskites (MHPs). Two‐dimensional (2D) halide perovskites among them have drawn a lot of attention for supercapacitor uses because of their outstanding photoactive characteristics and electronic‐ionic conductivity. Various facets of 2D halide perovskites—including their structural features, synthesis procedures, electrode fabrication approaches, and electrochemical characterisation for usage in supercapacitors—are investigated in this study. Several synthesis techniques for 2D halide perovskites are explored; inverse temperature crystallisation turns out to be the most successful one. The potential of the 2D perovskite with halide compound (Arg 2 MA 2 Sn 3 Cl 10 ) is investigated in photo‐rechargeable electrochemical supercapacitors specifically. Under illumination and in the dark at a scan rate of 10 mV/s, this material shows a specific capacitance of 49.09 F/g and an optical bandgap of 3.67 eV, therefore underlining its photo‐rechargeable capacity. It also achieves respectively 20.55 and 80 W/kg power and energy densities. Overall, especially in the construction of next‐generation supercapacitors, this review emphasises the amazing possibilities of 2D halide perovskites as sophisticated materials for energy storage.