Heteroatom-Doped Graphene-Based Materials for Energy-Relevant Electrocatalytic Processes

To address aggravating energy and environment issues, inexpensive, highly active, and durable electrocatalysts as noble metal substitutes both at the anode and cathode are being actively pursued. Among them, heteroatom-doped graphene-based materials show extraordinary electrocatalytic performance, some even close to or outperforming the state-of-the-art noble metals, such as Pt- and IrO2-based materials. This review provides a concise appraisal on graphene doping methods, possible doping configurations and their unique electrochemical properties, including single and double doping with N, B, S, and P. In addition, heteroatom-doped graphene-based materials are reviewed as electrocatalysts for oxygen reduction, hydrogen evolution, and oxygen evolution reactions in terms of their electrocatalytic mechanisms and performance. Significantly, three-dimensional heteroatom-doped graphene structures have been discussed, and those especially can be directly utilized as catalyst electrodes without extra binders and supports.