Characterization of few-layer 1T-MoSe2 and its superior performance in the visible-light induced hydrogen evolution reaction

Based on earlier results on the photocatalytic properties of MoS2, the 1T form of MoSe2, prepared by lithium intercalation and exfoliation of bulk MoSe2, has been employed for the visible-light induced generation of hydrogen. 1T-MoSe2 is found to be superior to both 2H and 1T MoS2 as well as 2H-MoSe2 in producing hydrogen from water, the yield being in the 60–75 mmol h−1 g−1 range with a turn over frequency of 15–19 h−1. First principles calculations reveal that 1T-MoSe2 has a lower work function than 2H-MoSe2 as well as 1T and 2H-MoS2, making it easier to transfer an electron from 1T-MoSe2 for the production of H2.