Emerging energy and environmental application of graphene and their composites: a review

Graphene-based materials receive attention in the field of energy and environmental application. The unique physiochemical assets such as the high surface area, high thermal stability, chemical flexibility, high electron mobility and mechanical solidity make it a highly versatile material for different applications. In this critical review, the application of graphene-based material in energy and environmental remediation is discussed in detail. More specifically, the role of graphene in thought-provoking research fields, viz. solar cell, photocatalytic water splitting, photocatalytic degradation of organic pollutants and heavy metal removal, is focused. As graphene possesses very good carrier mobility, it enhances the photocatalytic performance of semiconducting materials. Very interestingly, graphene is being used in both hole transport layer and electron transport layer in solar cell. Similarly, high surface area of graphene assists in heavy metal removal by adsorption. The challenges and recent achievements in these fields are highlighted in this review.