Chapter 1:Introduction: Hierarchical Nanostructures for Energy Devices

Energy has been the hottest social issue for a long time. Energy issues have been related to the problems associated with current major energy sources such as fossil and mineral energy sources. Renewable energy sources, such as hydroelectric, solar, wind, hydrothermal, biomass and nuclear power, are expected to solve the problems associated with fossil fuels. However, energy issues are becoming more serious global problems This chapter introduces the subject matter covered in the book and discusses the concepts of the energy cycle and the role of hierarchical nanostructures in efficient energy devices.