Advance and prospect of carbon quantum dots synthesis for energy conversion and storage application: A comprehensive review

Carbon nanomaterials such as carbon quantum Dots (CQDs) and graphene quantum dots (GQDs) have been attracting a great deal of attention recently due to their unique properties in terms of electrical conductivity, thermal stability, mechanical strength, chemical resistance, photoluminescence, low cost, and facile surface functionalization. By virtue of their rapid electron transfer and large surface area, CQDs and GQDs are desirable in these electrochemical applications. Carbon nanomaterials are widely used in various applications, including semiconductors, photovoltaic energy storage, biomedicals, drug delivery, environmental sectors, supercapacitors, electrocatalysis, and energy conversion applications. However, energy storage and conversion techniques are developing rapidly as new promising approaches emerge to solve some of the unprecedented challenges in energy at a low cost and with a low environmental footprint. This review examines the advancement of CQDs in energy conversion applications, supercapacitors, solar cell applications, and electrocatalysis with their synthesis approach.