Iron-molybdenum sulfides heterostructured nanosheet arrays for highly efficient hydrogen evolution reaction

1T MoS2 is identified as a hopeful rising star to substitute noble-metal catalysts for the electrocatalytic application. But the insufficient active sites and poor stability impede its large-scale applications. In this study, the novel Fe7S8/1T MoS2 heterostructured nanosheet arrays were prepared on iron foam through a facile hydrothermal approach as the highly efficient electrocatalysts for the first time. Fe7S8/1T MoS2 AA0.03 nanosheet arrays exhibited the extra low overpotential of 9 mV and 162 mV at 10 mA/cm2 and 100 mA/cm2 for HER, and the low overpotential of 183 mV at 10 mA/cm2 for OER. The assembled Fe7S8/1T MoS2 AA0.03//Fe7S8/1T MoS2 AA0.03 cell only need 1.41 V (2.15 V) to drive 10 mA/cm2 for overall alkaline water (natural seawater) splitting with remarkable cycle stability for 48 h. This novel strategy provides a pathway for the rational design of dualfunction electrocatalysts.