Molybdenum diselenide – black phosphorus heterostructures for electrocatalytic hydrogen evolution

The hydrogen evolution reaction (HER) is promising in the production of clean and sustainable energy and molybdenum diselenide (MoSe₂) is attractive for this process due to the excellent catalytic ability. However, its low intrinsic conductivity and vulnerability to aggregation have restricted wider application. Herein, a facile strategy to construct a heterostructure composed of MoSe₂ nanosheets and black phosphorus (BP) nanosheets by van der Waals (vdW) interactions is designed and described. Compared with the bare MoSe₂ nanosheets, the MoSe₂-BP heterostructure has improved conductivity and more abundant active sites attributable to BP consequently facilitating electron transfer and preventing MoSe₂ from aggregation. In the HER assessment, the MoSe₂-BP heterostructure delivers excellent electrocatalytic performance such as a low onset potential (200 mV), small Tafel slope (97 mV·dec⁻¹), and excellent stability. The 2D heterostructured semiconductor has great potential in electrocatalytic applications.