The inertness of in-plane S atoms in MoS₂ leads to unsatisfactory performance in hydrogen evolution reaction (HER). Herein, we fabricate an efficient MoS₂-based catalyst (O-MoS₂) with oxygen substituting a little part of sulfur in MoS₂. Because the introduced O heteroatoms have the stronger electronegativity than S, the inert basal surface is activated, providing numerous active sites, improving the electrical transmission efficiency, and inducing the transition from the 2H to 1T phase of MoS₂. The overpotential of as-fabricated O-MoS₂ at 10 mA/cm² is only 120 mV in alkaline electrolyte. Density functional theory calculations demonstrate that introducing O heteroatoms into MoS₂ optimizes the adsorption of H∗ and decreases the Gibbs free energies of the water dissociation, thus improving the HER performance significantly. This work paves a new way to enhance the electrocatalytic activity by introducing heteroatoms with electronic modulations.

MoS _{2 中}面内S原子的惰性导致析氢反应(HER)的性能不令人满意。在此，我们制造的高效的MoS ₂基催化剂（O-MOS ₂）与氧气在的MoS代硫的一小部分₂。由于引入的O杂原子比S具有更强的电负性，惰性基面被激活，提供了许多活性位点，提高了电传输效率，并诱导了MoS ₂从2H相到1T相的转变。在 10 mA/cm ^{2 时}制造的 O-MoS ₂的过电位在碱性电解液中仅为 120 mV。密度泛函理论计算表明，将O杂原子引入MoS ₂优化了H*的吸附并降低了水解离的吉布斯自由能，从而显着提高了HER性能。这项工作为通过引入具有电子调制的杂原子来增强电催化活性铺平了道路。