**Two‐Dimensional Transition Metal Dichalcogenides for Electrocatalytic Energy Conversion Applications**

Fengwang Li and Mianqi Xue

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/63947

## **Abstract**

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62 Two-dimensional Materials - Synthesis, Characterization and Potential Applications

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Electrocatalytic energy conversion using renewable power sources is one of the most promising ways for energy storage and energy utilization in the new century. Specific catalysts are needed to improve the electrocatalytic reactions. Two‐dimensional transition metal dichalcogenides (2D TMDs) have attracted considerable interest as alternatives to noble metal catalysts due to their unique electronic structure and high catalytic activity. Over the past years, a great number of 2D TMD‐based catalysts have been explored for various electrocatalytic reactions, such as the hydrogen evolution reaction (HER) as a half reaction of water splitting and CO2 reduction reaction as part of artificial photosynthesis. This chapter provides an overview of recent progress on TMD‐based electrocatalysts, including mechanism understanding of the advantages of 2D materials, especially 2D TMDs and the up‐to‐date synthesizing approaches of TMDs, and state‐of‐the‐art applications of TMDs in electrocatalytic reactions, and finally outlines the current challenges and future opportunities.

**Keywords:** 2D materials, transition metal dichalcogenide, electrocatalysis, water split‐ ting, hydrogen evolution reaction, CO2 reduction reaction, artificial photosynthesis
