1D/2D Heterostructures as Ultrathin Catalysts for Hydrogen Evolution Reaction.

2D MoS2 has emerged as a promising alternative to Pt-based catalysts for hydrogen evolution reaction (HER) due to its low cost and earth abundance. However, insufficient active sites of basal plane and poor conductivity become the foremost factors restricting the catalytic performance of MoS2 . Here, a facile strategy is presented to enhance the HER performance of MoS2 by converting its 2D structure into 1D/2D heterostructures of Mo6 Te6 /MoS2(1- x ) Te2 x by the in situ tellurization. As-prepared 1D/2D heterostructures exhibit excellent HER performance with the Tafel slope of ≈56 mV dec-1 (only one-third of that for pristine MoS2 ). The enhanced HER catalytic activity is attributed to more Te/S vacancies introduced by tellurization, which serve as the active sites as suggested by theoretical calculations. Besides, the formation of highly conductive well-aligned quasi-1D Mo6 Te6 nanobelts facilitate charge transport in HER. Previous work provides a facile approach to construct mixed dimensional materials, and opens up a new avenue to the properties modulation of 2D transition metal chalcogenides.