This book introduces the basic knowledge and recent process of nanogenerators. Chapter 1 introduces the energy problem people meet recently and points out that renewable and green energy resources are useful methods to solve the problem about global warming and energy crises. Chapter 2 is about the first nanogenerator based on ZnO materials. Chapter 3 gives theory for piezoelectricity, two important contacts in nanogenerator, n-type and p-type nanogenerators. Chapter 4 is piezoelectric polymer nanowires. The Appendix I lists selected paper of the author in the field of piezoelectrics and its related application. Appendix II gives detailed information about how to build an experimental setup for energy harvesting. The research work was supported by CSC-DAAD scholarship (CSC No. 201500110019 and DAAD No. 57165010) funded by China Scholarship Council and Deutscher Akademischer Austauschdienst, Shanghai Sailing Program funded by Science and Technology Commission of Shanghai Municipality (Grant No. 15YF1413900), the International Postdoctoral Exchange Fellowship Program (Grant No. 20150057) and Project funded by China Postdoctoral Science Foundation (Grant No. 2014M560357).

Dr. Jiajun Zhu is a research physicist in Shanghai Institute of Technical Physics, Chinese Academy of Sciences. Currently, he has been awarded a DAAD Fellowship, working in Helmholtz-Zentrum Dresden-Rossendorf, Germany. Before that, he worked in Key Laboratory of Polar Materials and Devices, Ministry of Education, East China Normal University.