Energy is a major challenge for humans in the context of climate change and increasing population. In particular, global warming is partly due to CO2 emissions from the excessive use of fossil fuels such as oil, coal and gas. Research has thus recently focused on sustainable biofuels and energy storage. In particular, nanomaterials and metal oxides are enhancing the efficiency of batteries, supercapacitors, fuel cells and electronics. For instance, optoelectronic devices consume much less power than classical devices. Materials for rechargeable batteries are presented in Chap. 1 by Balaji Sambandam et al., with emphasis on electro chemical properties of metal oxide-based electrode materials for energy storage. In Chap. 2, Akhila Das et al. review molybdenum disulphide supercapacitors and high performance electrodes. Chapter 3 by Ryan D. Corpuz et al. highlights the devel opment of manganese oxide as cathode material in rechargeable zinc ion batteries (Figure). Shanmuga Sundar et al. review conductive oxides in the fabrication and application of flexible electronic devices in Chap. 4. Chapter 5 by Ramarajan et al. summarizes major findings on SnO2 doped with Sb and Sb-Ba, Nb and Ta using spray pyrolysis.