CuO Nanoparticle‐Loaded TiO 2 Catalyst for High‐Performance Photocatalytic Hydrogen Peroxide Generation

Abstract Titanium dioxide (TiO 2 ) has been extensively investigated in photocatalysis due to its high stability, low toxicity, and biocompatibility. However, its application in hydrogen peroxide (H 2 O 2 ) production is hindered by the rapid recombination of photogenerated charge carriers and the poor selectivity of the two‐electron oxygen reduction reaction (2e − ORR). Here, a CuO/TiO 2 photocatalyst is reported, in which CuO nanoparticles are anchored on the TiO 2 surface as cocatalysts to provide additional active sites and promote efficient separation of photogenerated electrons and holes. The optimized CuO/TiO 2 exhibits a remarkable photocatalytic H 2 O 2 production rate of 19.48 mmol g −1 h −1 , which is 162 times higher than that of pristine TiO 2 , with excellent stability sustained over 7 h’ continuous irradiation. The apparent quantum yield (AQY) of CuO/TiO 2 reaches 7.30% at 365 nm. Notably, the CuO/TiO 2 demonstrated the promising H 2 O 2 production in pure water (182.31 µmol g −1 h −1 ). Femtosecond transient absorption spectra (Fs‐TAS) reveal that the average lifetime of photogenerated electrons in CuO/TiO 2 is 5.8 times longer than in TiO 2 , confirming the enhanced charge separation and transfer. In situ spectroscopic analyses further demonstrate that CuO/TiO 2 facilitates both oxygen reduction and water oxidation pathways. These results highlight CuO/TiO 2 as a cost‐effective and efficient photocatalyst for sustainable H 2 O 2 production.