Engineering Cu/TiO2@N-Doped C Interfaces Derived from an Atom-Precise Heterometallic CuII4TiIV5 Cluster for Efficient Photocatalytic Hydrogen Evolution

Engineering interfaces is an effective method to create efficient photocatalysts by reducing the recombination of photogenerated carriers. Still, there is a lack of proficient strategies to construct suitable interfaces. In this work, we design and synthesize an atom-precise heterometallic Cu II 4 Ti IV 5 cluster, [Ti 5 Cu 4 O 6 (ba) 16 ]·2CH 3 CN ( 1 , Hba = benzoic acid), which is used as a precursor for fabricating efficient photocatalytic interfaces. The cluster has a precise composition and structure with hierarchical bimetal atom distribution and favorable binding properties. The resulting Cu/TiO 2 @N-doped C interfaces are obtained via the thermal treatment. Combined Cu/TiO 2 with N-doped C interfaces provide multiple channels for the transmission of photogenerated carriers and effectively reduce the recombination probability of photogenerated charge carriers. Consequently, the novel interface structure exhibits an excellent hydrogen evolution rate via the photocatalytic water splliting. Density functional theory calculations also support high activity of the interfaces toward hydrogen evolution. As a proof-of-concept application, we show that choosing well-defined metal clusters as precursors can offer a valuable method for engineering photocatalytically efficient interfaces.