Greener nanomaterials and their diverse applications in the energy sector

Energy crisis is a matter of serious global concern as the depleting energy sources exert a deleterious effect on the economy. Additionally, the existing sources of energy are brimming with deleterious side effects on human health and the environment. Hence, a global effort is being made for the utilization of green chemistry for sustainable energy applications and for curbing the degradation of environment associated with the use of large-scale energy devices, and thermoelectric vehicles. Green chemistry, coupled with nanotechnology, offers a technological innovation in the domain of energy sources and subsequent energy conversion. Nanostructuring of energy-active materials notably enhances the performance of the devices due to enhancement in specific surface area, increased number of catalyst centers among others; environmental sustainability and reduced toxicity being the added benefits. This review briefly deliberates the synthesis pathways for 'greener' nanomaterials and their current applications in energy conversion, which may help address the issue of global energy demand. The review aims to endorse the immense potential of bio-based nanostructures in assorted thermal and energy applications, providing a deep insight into further prospects of their appliances that requires deeper understanding and strategic research. The various sectors of energy research where assorted bio-based nanomaterials may find appliances have been discussed. The current challenges and existing limitations in utilizing greener nanomaterials in the energy sector have also been highlighted.