Metallic-phase two-dimensional transition-metal dichalcogenides for electrochemical applications

In 2011, we reported facile synthesis of metallic-phase two-dimensional transition-metal dichalcogenide (TMD) nanosheets. This method allows access to metallic materials that are atomically thin and therefore possess properties that are fundamentally different from their bulk counterparts. Since then, thousands of papers have reported synthesis and new applications of metallic atomically thin nanosheets. Over the past 15 years, metallic TMD nanosheets have emerged as leading materials for electrochemical applications in catalysis, supercapacitors, and lithium–sulfur batteries. In this article, we summarize the fundamentals of TMDs and highlight the interesting properties of the metallic phase for electrochemical applications. We then provide insights into key challenges that remain in synthesis and applications of metallic TMD nanosheets.