Our research aims to explore the advanced materials for energy conversion and storage. We are particularly interested in graphene based composites and 2D transition metal dichalcogenides. We have used the above-mentioned nanomaterials as the electrode materials for supercapacitors and lithium ion batteries. Regarding the aspect of energy conversion, we focus on the development of bifunctional electrocatalysts for overall water splitting. To understand the concepts and mechanisms of electrode reactions, we have established a series of in-situ methods for LIB research.