Applications of graphitic carbonaceous materials in photosupercapacitors: Recent breakthroughs and future perspectives

Photosupercapacitors (PSCs) have recently attracted extensive research interest as one of the most promising energy storage devices owing to their self-charging attributes, small sizes, portability, lightweight, and ability to support emerging wearable electronics. With the recent emergence of high-specific energy density (E s ) applications, including powering hybrid and electric vehicles, noteworthy research efforts are centred on increasing electrochemical performance, cost-effectiveness, and cycle lifespan of PSCs. This is being pursued by developing low-cost electrode materials with high reversible capacity and E s . One potential route to advancements in PSCs is turning to graphitic carbonaceous materials as promising electrode materials. Graphitic carbonaceous materials can be favourably derived from waste biomass, offer tailorable porosity and electro-active area, promote exciton dissociation during PSC charging by acting as electron transport layers, function dually as counter electrodes in solar cells and as electrodes in SCs, and are compatible with binder-free designs, among other merits. Therefore, this review focuses on the current understanding of the shortfalls and merits of using graphitic carbonaceous materials in PSCs. It also highlights the challenges and provides recommendations for improvement regarding PSC design, electrolyte selection, material compatibility, binder usage, fabrication processes, characterisation protocols, and components. Finally, the merits, demerits, and prospects of employing graphitic carbonaceous materials to advance PSC sustainability and performance are outlined. • Photosupercapacitors (PSCs) combine light harvesting and energy storage. • PSCs are self-charged, small-sized, portable, and lightweight. • Graphitic carbonaceous materials are suitable for PSCs to solve critical setbacks. • Graphitic carbonaceous materials are advantageously abundant for upscaling. • Developing PSCs support net-carbon-zero and cost-effective energy accessibility.