Water splitting photocatalysts can be tracked in first-principles simulation. This involves probing versatile series of changes to atomistic models until the calculated properties morph to perfection. In this article, a design process as such unfolds. First, a prescriptive guideline is derived to obtain semiconductive derivatives of the CoO2 monolayer. This inspires the drawing of a set of bilayers consisting of CoO2 on ZrS2, with H, La, and Ni impurities. Precisely tuned redox potentials and a supportive built-in electric field manifest in DFT simulations when these impurities are balanced in appropriate ratios. It is shown how charge redistributions and the formed interlayer and intralayer dipoles underpin this outcome. The LaZr16S32/Co14Ni14O45(OH)11 bilayer is identified as a promising water splitting photocatalyst. The system is remarkable because of its polarized semihybridized single-gap electronic structure. Initial prospects on mechanistic properties are also provided, suggesting that 3Ni-coordinated oxygen promotes water splitting through enhanced vacancy formation. The work provides conceptual enrichment for any researcher in the field of photocatalysis.
Celis et al. (2026) studied this question.