Chapter 10 - Graphene quantum dots for clean energy solutions

Abstract

Energy obtained from renewable sources is known as clean energy, because of its pollution-free and eco-friendly nature. Many different and advanced materials are usually employed as electrode materials for clean energy solutions. Carbon nanomaterials offer different groups such as carbon quantum dot, graphene quantum dots (GQDs), and carbon nanorod, which are used for energy electrode materials. GQDs are emerging and attractive carbon nanomaterials for energy storage devices due to their excellent and remarkable properties like high mobility, excellent transparency, large surface area, and fluorescence characteristics. The present chapter highlights the significant potential of GQDs which are used in energy generation and storage devices. Moreover, the brief introduction of synthesis techniques of GQDs, which are categories into two groups: (1) top-down and (2) bottom-up methods. Apart from this, the chapter has been focused to explore the respective advantages and disadvantages of the synthesis techniques. Generally, GQDs and GQD-based nanocomposites are promising and attractive materials in the area of energy storage and conversion devices such as supercapacitors, batteries (Li-ion battery), and solar cells. Recently, GQDs-based electrode materials with quantum confinement effect and edge effect also open a new path and have great potential for new energy storage devices. Furthermore, the limitation of GQDs in the area of energy conversion and storage devices is also highlighted as a future perspective of GQD's research and challenges.