Activation of BaTaO2N Photocatalyst for Enhanced Non‐Sacrificial Hydrogen Evolution from Water under Visible Light by Forming a Solid Solution with BaZrO3

No sacrifice needed! Activation of perovskite-type BaTaO2N (band gap: 1.8–1.9 eV) to improve photocatalytic activity for non-sacrificial H2 evolution from water under visible light (λ>420 nm) was achieved by forming a solid solution with BaZrO3, improving the performance six- to ninefold (see figure). The improvement is attributable to the increased driving force for the redox reactions and the reduced density of defects, which minimizes the undesirable electron–hole recombination.