Abstract
Supercapacitors have garnered significant research interest as high-performance energy storage devices, owingto their high power density and excellent recyclability. Advances in efficiencyand flexibility have led to the development of photosupercapacitors, whichstore charge electrochemically using solar energy. The performance andefficiency of a photosupercapacitor are primarily determined by the materialsused in its fabrication. Halide perovskites have become a popular material forsupercapacitors and photosupercapacitors, because of their high crystallinity, charge storage capacity, electrochemical properties, ease of synthesis, andcost-effectiveness. Although challenges remain in the reproducibility, reliability, and long-term performance of their devices. This article aims topresent a comprehensive review of the applications and advancements of halideperovskites in supercapacitors and photosupercapacitors. Initially, thestructural aspects of halide perovskites are introduced, and then the workingprinciples and insights of both applications are briefly discussed.Subsequently, the progress of halide perovskites in supercapacitors andphotosupercapacitors is thoroughly discussed. Likewise, the limitationsassociated with the perovskite-based supercapacitors and photosupercapacitorsand their progress achieved to overcome the limitations have been discussed. Inthe end, current challenges associated with halide perovskites, theirsupercapacitor devices, possible solutions, and future perspectives are summarised.