Carbon Materials-based Electrocatalysts for Oxygen Reduction Reaction

Abstract

With the rapid economic development, the demand for energy storage devices has become urgent. As a representative of emerging energy techniques, fuel cell has been extensively explored in electrochemical energy conversion and storage. In fuel cells, fuels are oxidized on anode, and the released electrons transfer through the external circuit to the cathode where O2 is reduced. The sluggish kinetics of cathode oxygen reduction reaction (ORR) limits their broad range of applications. Nobel metal Pt loaded on carbon (Pt/C) has been regarded as a state-of-the-art catalyst for ORR. Nonetheless, it still suffers from intrinsic drawbacks such as low abundance in nature, high cost, and poor stability. Owing to the high activity and low cost of carbon materials, researchers have increasingly become interested in the development of efficient, inexpensive, durable carbon-based catalysts. In this chapter, a comprehensive review of carbon-based materials for ORR is presented. The mechanism of the ORR reaction is briefly highlighted. Then various typical carbon-based materials, including platinum group metal (PGM)-based carbon materials, transition metal (TM)-based carbon materials, and metal-free carbon materials, are mainly discussed. Finally, the developments and future directions of carbon-based materials in ORR are provided.