Interfacially bonded CuCo 2 O 4 /TiO 2 nanosheet heterostructures for boosting photocatalytic H 2 production

Constructing high-performance, economical and environmentally friendly photocatalysts remains a challenge for the efficient conversion of solar energy. In this work, CuCo 2 O 4 nanoparticles modified on TiO 2 nanosheets have been designed and fabricated via a facile hydrothermal method followed by an in situ calcination process. The resultant 10%-CuCo 2 O 4 /TiO 2 heterostructure exhibited superior photocatalytic activity under full spectra. The H 2 generation rate can reach 4830 μmol g −1 h −1 under 300 W Xe lamp irradiation, which is 32 times higher than that of pristine TiO 2 and the highest fold increase of a binary TiO 2 -based non-noble system reported so far. Its apparent quantum yield (AQY) value can reach 11.5% at 365 nm. Furthermore, we demonstrate that there are chemical bonds formed at the interface between well-dispersed CuCo 2 O 4 and TiO 2 by XPS spectrometry and electronegativity theory, and the efficient separation of charge carriers due to the p–n junction adopting the interfacial Ti–O–Cu/Co bonds is crucial for the improved performance and photostability. This work develops possibilities to prepare feasible CuCo 2 O 4 -based heterostructures for energy conversion.