The major topical and societal issues of energy transition and environmental conservation have benefited from the contribution of nanotechnologies and nanomaterials. Nanomaterials, including carbon-based newcomers, have helped to improve in particular the performance of energy storage and conversion devices. Some of these nanomaterials, including fullerenes, carbon nanotubes, nanodiamonds and carbon dots, were discovered well before the 2000s. Others are more recent, including graphene (the leading material of the 21st century) as well as many mineral materials developed at the nano scale: atomic clusters, metal or semiconductor nanoparticles, two-dimensional inorganic materials, metal-organic frameworks (MOF) and luminescent quantum dots. All of these are involved in the realization of devices for energy purposes. Nanotechnology and Nanomaterials for Energy provides a critical analysis of the latest work in the fields of batteries, photovoltaics, fuel cells and catalysis as well as lighting, with the advent of light-emitting diodes.