Highly active hydrogen evolution catalysis from metallic WS sub(2) nanosheets

We report metallic WS sub(2) nanosheets that display excellent catalytic activity for hydrogen evolution reaction (HER) that is the best reported for MX sub(2) materials. They are chemically exfoliated from WS sub(2) nanostructures synthesized by chemical vapour deposition, including by using a simple and fast microwave-assisted intercalation method. Structural and electrochemical studies confirm that the simultaneous conversion and exfoliation of semiconducting 2H-WS sub(2) into nanosheets of its metallic 1T polymorph result in facile electrode kinetics, excellent electrical transport, and proliferation of catalytically active sites.