The effects of the fluence of electron irradiation on the structure and hydrogen evolution reaction performance of molybdenum disulfide

Controllable and stable 1T phase MoS₂ nanosheets (MoS₂ NSs) were obtained by 1 MeV electron irradiation for the first time, and the hydrogen evolution reaction (HER) performance was improved. We propose that the synergistic effect of electron excitation and vacancy formation, and mechanical strain are the main factors causing the phase transition from the 2H to 1T phase in MoS₂ NSs induced by electron irradiation. It was found that the irradiation-induced defects in the catalysts could provide abundant active sites, while 1T phase MoS₂ NSs with excellent electrical conductivity would greatly improve the interfacial charge transfer rate, which is beneficial for improving the catalytic performance. In addition, the appropriate irradiation fluence is the key factor to improve the HER performance of MoS₂ NSs. Therefore, the application of the electron irradiation method provides a new strategy to enhance the HER performance of MoS₂ NSs.