MoS2 Moire Superlattice for Hydrogen Evolution Reaction

A MoS2 moire superlattice with a twisted angle of theta approximate to 7.3 degrees via a facile method instead of a conventional mechanical stacking method is successfully fabricated. With reduced interlayer potential barriers demonstrated by first-principles calculations and ultralow frequency Raman spectra, electrons can transfer easily from a conductive substrate to active sites in this MoS2 superlattice, thus leading to good hydrogen evolution reaction (HER) activities. By using an electrochemical microcell technique, improved catalytic performance in the MoS2 moire superlattice is validated, with a current density of -10 mA/cm(2) at an overpotential of -153 mV and a Tafel slope of 73 mV/dec. A strategy to boost the electrocatalytic performance by reducing the interlayer potential barriers is successfully achieved by employing a MoS2 moire superlattice. The work paves a new pathway to break the bottleneck for further improvement of HER performance and interesting possibilities for implementing moire superlattices in catalysis, energy storage, and 2D functional also opens devices.