Au-NPs embedded Z–scheme WO₃/TiO₂ nanocomposite for plasmon-assisted photocatalytic glycerol-water reforming towards enhanced H₂ evolution

Au-NPs-embedded Z-scheme WO₃/TiO₂ hetero-junction for boosting photocatalytic H₂ evolution from glycerol-water mixture under visible light has been investigated. The composite samples, synthesized by a sol-gel assisted photo-deposition method, gave higher visible light absorption through Surface Plasmon Resonance (SPR), larger BET surface area and hindered recombination of charge carrier. Highest H₂ evolution rate of 17200 ppm h⁻¹ gcat⁻¹ was obtained over 0.5%Au-loaded WO₃/TiO₂ which was 4.46 and 5.89 folds higher than WO₃/TiO₂ and TiO₂, respectively. This divulges that constructing WO₃/TiO₂ Z-scheme hetero-junction adjusted redox potential, while decorating plasmonic Au-NPs enables faster charges separation with higher visible-light absorption through SPR, resulting in superior H₂ production. In addition, both water splitting and photocatalytic glycerol reforming contributed towards excellent H₂ formation. The apparent quantum yield of 28.3% (λ ~ 420 nm) was attained and catalyst prevailed photo-stability for H₂ evolution in cyclic runs. This study provides new insight about constructing plasmonic assisted Z-scheme assembly for solar fuels production.