Novel two-dimensional ZnO materials for enhanced photocatalytic hydrogen evolution performance

Developing efficient photocatalysts is crucial for addressing energy and environmental challenges. Two-dimensional (2D) materials have unique advantages in this regard, such as large surface area and tunable electronic properties, which can enhance photocatalytic performance. However, current 2D ZnO materials, such as graphene-like ZnO (g-ZnO), exhibit limited solar light absorption and inefficient catalytic activity for the hydrogen evolution reaction (HER). In this study, we predict two stable novel 2D ZnO monolayer materials, named SOD-110 and SOD-111, based on density functional theory calculations. SOD-110 outperforms g-ZnO in terms of bandgap width, light absorption, and Gibbs free energy metrics. Moreover, the substitution doping of elements from the same-group in the periodic table can further adjust the performance of SOD-110 to meet practical photocatalytic requirements. Among the doped structures, Te-doped SOD-110 with its near-ideal value (0.01 eV) of Gibbs free energy for HER and higher solar-to-hydrogen efficiency (11.77 %), emerges as a highly promising 2D ZnO-based photocatalyst.