Jamdagni Pooja, Pandey Ravindra, Tankeshwar K
Department of Physics, Guru Jambheshwar University of Science and Technology, Hisar 125001, India.
Department of Physics, Central University of Haryana, Mahendragarh 123031, India.
Nanotechnology. 2021 Oct 22;33(2). doi: 10.1088/1361-6528/ac2d46.
By employing the state-of-the-art density functional theory method, we demonstrate that Janus WSeTe monolayer exhibits promising photocatalytic properties for solar water splitting. The results show that the monolayer possesses thermodynamic stability, suitable bandgap (∼1.89 eV), low excitons binding energy (∼0.19 eV) together with high hole mobility (∼10cmVs). Notably, the results suggest that the oxygen evolution reaction can undergo spontaneously without any sacrificial reagents. In contrast, the overpotential of hydrogen evolution reaction can partially be overcome by the external potential under solar light irradiation. Furthermore, the intrinsic electric field induced by the symmetry breaking along the perpendicular direction of Janus WSeTe monolayer not only suppresses the electron-hole recombination but also contributes to the solar-to-hydrogen efficiency, which is calculated to be ∼19%. These characteristics make the Janus WSeTe monolayer to be a promising candidate for solar water splitting.
通过采用最先进的密度泛函理论方法，我们证明了Janus WSeTe单层在太阳能水分解方面具有良好的光催化性能。结果表明，该单层具有热力学稳定性、合适的带隙（约1.89 eV）、低激子结合能（约0.19 eV）以及高空穴迁移率（约10 cmVs）。值得注意的是，结果表明析氧反应可以在没有任何牺牲试剂的情况下自发进行。相比之下，在太阳光照射下，外加电势可以部分克服析氢反应的过电势。此外，沿Janus WSeTe单层垂直方向的对称性破缺所诱导的内建电场不仅抑制了电子 - 空穴复合，还提高了太阳能到氢能的效率，经计算约为19%。这些特性使Janus WSeTe单层成为太阳能水分解的一个有前景的候选材料。
