Energy serves as the foundation for human progress. The ever-increasing consumption due to population growth threatens traditional energy sources. Converting clean and renewable natural resources like sunlight, wind, and water into usable forms such as electricity and mechanical energy presents an apparent solution to the current energy crisis. Material scientists are actively engaged in addressing this challenge through the development of sustainable energy materials. Energy materials encompass a broad range of materials involved in producing, storing, transporting, and utilizing energy. The efficiency of energy conversion and handling relies heavily on the utilization of appropriate materials. However, no ideal energy material has all the desired properties. Hence, it becomes necessary to modify the properties of materials to meet specific application requirements. This can be achieved through external means such as doping, thermal treatment, composite formation, and strain engineering. This chapter focuses on the tuning of properties of energy materials from the perspective of their application. Microstructure and morphology, doping, and composites are crucial properties, significantly contribute to developing sustainable energy technologies. These properties are categorized and extensively discussed due to their importance in this field.