Multiple-atomic asymmetry effect on polarization-controlled photocatalytic properties in two-dimensional single-layer...

Two-dimensional asymmetric materials with intrinsic polarization are promising for photocatalytic water-splitting applications. However, achieving efficient polarization modulation in a single asymmetric material to promote photocatalytic solar-to‑hydrogen conversion remains challenging, given that it requires photocatalysts capable of controlled polarization with promoted catalytic reactions. Here, using the first-principles calculation, we report that the catalytic activities can be enhanced by adjusting multiple-atomic asymmetry in a single-layer material of MoSiGeX₂Y₂ (X, Y = N, P, As; X ≠ Y). The regulation mechanism of multiple-atomic asymmetry on the photocatalytic process is thoroughly elucidated. Benefiting from the enhanced polarization induced by multiple-atomic asymmetry, the energy barriers for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in the MoSiGeP₂N₂ monolayer are significantly decreased, thereby improving photocatalysis. Moreover, its efficient optical absorption and high photocurrent peak endow MoSiGeP₂N₂ excellent photoelectric conversion behavior. This work reveals the effect of multiple-atomic asymmetry on polarization-controlled photocatalysis and offers new insights for boosting photocatalytic performance.