The world is in short supply of energy. Along with environmental factors, it has become crucial for science to provide solutions. Energy Materials is a significant area of research in material science. The various aspects of energy include electrical power, comprising batteries, supercapacitors, thermoelectric energy conversion, photovoltaics, etc. Hydrogen is available in abundance, but catalysts are needed for the catalysis, so catalysts or porous solids have universal appeal in usage and applications. Then there are nuclear energy materials. Overall, energy materials have now captured the most attention worldwide in research and investment. This book covers various sections that are currently exploring energy solutions through materials.