The first-principles calculation within the density functional theory (DFT) is used to study the hydrogen evolution reaction (HER) activity and related electronic properties of monolayer black phosphorus under the uniaxial strains. Herein, it is found that different compressive and tensile strains would modulate the Gibbs free energy (ΔG_H*), partial charge density of the lowest unoccupied state (ε_LUS), and band structure of black phosphorene. Specifically, as the ΔG_H* decreases, the HER activity of phosphorene system with uniaxial strain is improved except for the +3% strain case. Importantly, the HER catalytic performance of phosphorene can be reduced by 0.4 eV and the bandgap decreased to 0.23 eV by applying the −10% strain. Comparing with strained-free case, the larger partial charge density of ε_LUS on the surface of black phosphorene shows more H adsorption sites for electrocatalysis. Moreover, the HER activity is related to the partial charge density of ε_LUS rather than the value of ε_LUS site. These results reveal that strain could effectively modulate the HER performance for electrocatalysis. And it is expected to provide further understanding in practical applications.

中文翻译：

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用于析氢反应活性的黑磷烯的应变调制

密度泛函理论（DFT）中的第一性原理计算用于研究单层黑磷在单轴应变下的析氢反应（HER）活性和相关电子特性。在此，发现不同的压缩和拉伸应变会调节吉布斯自由能（Δ G _H*）、最低未占据状态的部分电荷密度（ε _LUS）和黑磷_烯的能带结构。具体而言，作为 Δ G _H*降低，具有单轴应变的磷烯系统的 HER 活性提高，除了 +3% 应变情况。重要的是，通过施加 -10% 应变，磷烯的 HER 催化性能可以降低 0.4 eV，带隙降低至 0.23 eV。与无应变情况相比，黑色磷烯表面的ε _LUS部分电荷密度越大，电催化的 H 吸附位点就越多。此外，HER活性与ε _LUS的部分电荷密度有关，而不是ε _LUS位点的值。这些结果表明，应变可以有效地调节电催化的 HER 性能。并有望在实际应用中提供进一步的理解。