Abstract Half-reaction of water splitting is hydrogen evolution reaction (HER), which requires low cost and high activity catalysts. Two-dimensional (2D) transition metal carbon/nitrides (MXene) materials have shown great potential as highly efficient catalysts due to their excellent properties. In this work, the heteroatom X (X = N, B, P, S) doping effect on the HER of M2C MXene (M = Ti, Mo) with or without oxygen functional groups have been performed by well-defined density functional calculations (DFT). The X doped M2CT2 (M = Mo, Ti; T = O) exhibited better HER catalytic activity than the X doped pristine M2C (M = Mo and Ti). Moreover, the calculated Gibbs free energies of hydrogen adsorption (ΔGH) indicate that the N-doped Ti2CO2 has improved electrocatalytic activity than that of Pt(1 1 1). Additionally, based on the electronic structure of X-doped Ti2CO2, the electrical conductivity of N-doped Ti2CO2 is higher than that of pristine Ti2CO2.

中文翻译：

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揭示杂原子掺杂的 M2C MXene (M = Ti, Mo) 析氢反应的电化学机制

摘要 水分解的半反应是析氢反应（HER），需要低成本和高活性的催化剂。二维 (2D) 过渡金属碳/氮化物 (MXene) 材料由于其优异的性能而显示出作为高效催化剂的巨大潜力。在这项工作中，杂原子 X (X = N, B, P, S) 对带有或不带有氧官能团的 M2C MXene (M = Ti, Mo) 的 HER 的掺杂效应已通过明确定义的密度泛函计算进行（ DFT）。X掺杂的M2CT2（M=Mo，Ti；T=O）表现出比X掺杂的原始M2C（M=Mo和Ti）更好的HER催化活性。此外，计算出的氢吸附吉布斯自由能(ΔGH)表明，N掺杂的Ti2CO2比Pt(1 1 1)具有更高的电催化活性。此外，