(Mo + N) and (W+N) Co-doping as a new strategy for BaTiO3 piezo-photocatalysis (BaTiO3-PPS): A DFT investigation of enhanced water splitting

Piezo-photochemical water splitting is a promising pathway to achieving sustainable energy. Density functional theory (DFT) approach was used investigate BaTiO 3 photocatalysts strategically modified by (Mo + N) and (W + N) co-doping under strain to assess their piezo-photocatalytic performance. Co-doping and strain efficiently regulated electronic structure, band gap, and defect chemistry, improving visible-light absorption and catalytic activity. Hydrogen evolution reactions were favoured by intermediate temperature fluctuations and high carrier mobility. (Mo + N) co-doped BaTiO 3 exhibited superior performance with low overpotential and visible absorption up to 401 nm, but efficiency declined under strain due to band gap widening and increased energy barriers. Conversely, (W + N) co-doping maintained stable piezoelectric response and strong absorption across 400–600 nm, effectively balancing strain effects. Optimal strain conditions were 0.00 % for (Mo + N), all ranges for (W + N), and 0.04 % for pure BaTiO 3 . Overall, strategic co-doping synergistically combined N-induced defects with Mo/W d-orbital states, enhancing carrier mobility and absorption with multiple intensity peaks, better than individual W-, Mo-, or N-doping strategies. • Piezo-photocatalytic properties of (Mo + N) and (W + N) co-doped BaTiO 3 for hydrogen energy. • Induced strain efficiently regulates piezo-photocatalytic properties. • (Mo + N) co-doped BaTiO 3 exhibits superior performance because of low overpotential. • Strategic co-doping synergistically combined N-induced defects with Mo/W d-orbital states. • Carrier mobility, absorption with multiple intensity peaks, better than individual W-, Mo-, or N-doping.