Nanoscopic Wonders: Carbon Quantum Dots as Catalysts and Charge Carriers in Advanced Energy Storage Systems

Abstract

Research on the synthesis and uses of zero-dimensional (0D) carbon quantum dots (CQDs) has emerged as a dynamic and fascinating innovative area of study in current years. The exceptional characteristics of CQDs, such as their low cost, easy surface functionalization, nontoxicity, tunable photoluminescence, and chemical inertness, have drawn attention. Their possible uses span the biomedical, pharmaceutical, environmental, photocatalytic, and energy storage domains. Research on these has mainly concentrated on how they behave in biosensing, optoelectronics, and environmental sensing; however, energy storage systems are developing quickly as novel, capable approaches are coming up to address few of the unresolved problems with energy at affordable and ecological impact. Therefore, this review delves deeply into the effects of synthetic methods on the final product of CQDs and the fundamentals and properties of CQDs, including size-dependent properties and quantum confinement effects on electrochemical energy-related systems. This review also covers the design of CQD-based composites used as charge carriers in different energy storage materials (like batteries and supercapacitors) and as a catalyst in energy storage (like overall water splitting and oxygen reduction reaction). It also includes helpful recommendations for resolving the remaining issues in the field.