Defect engineering of two-dimensional materials for efficient electrocatalysis

Exploring high-activity and earth-abundant electrocatalysts for electrochemical reactions, including the hydrogen evolution reaction (HER), oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), etc. are crucial for building future large-scale green energy conversion and storage systems. Recently, some low-cost and resourceful two-dimensional (2D) semiconductor materials such as transition metal dichalcogenides (TMDCs) and layered oxides, have attracted increasing attention in electrocatalysis applications in virtue of their comparable catalytic activity and long-term stability to conventional noble metal-based catalysts (e.g. Pt/C, RuO2, IrO2, etc.). However, the intrinsic activity of some 2D materials still cannot meet the increasing requirement for highly efficient and reliable eletrocatalysts for future energy conversion and storage systems. In this context, designing elctrocatalysts with sufficient amount of active sites accessible for electrolyte, high activity of each active sites, and excellent conductivity is of great significance. To this end, defect engineering is a powerful strategy for tailoring the physical and chemical properties of 2D materials for efficient electrocatalysis. In this article, an overview of recent progress on defect engineering in 2D eletrocatalysts for HER, ORR and OER is presented. The effects of defects on the structure and tuned properties of 2D materials in eletrocatalysts applications are also summarized. Additionally, the challenges and opportunities ahead in this emerging field are also proposed. (C) 2018 The Chinese Ceramic Society. Production and hosting by Elsevier B.V.