This book describes various carbon nanomaterials and their unique properties, and offers a detailed introduction to graphene–carbon nanotube (CNT) hybrids. It demonstrates strategies for the hybridization of CNTs with graphene, which fully utilize the synergistic effect between graphene and CNTs. It also presents a wide range of applications of graphene–CNT hybrids as novel materials for energy storage and environmental remediation. Further, it discusses the preparation, structures and properties of graphene–CNT hybrids, providing interesting examples of three types of graphene–CNT hybrids with different nanostructures. This book is of interest to a wide readership in various fields of materials science and engineering.