Enhanced hydrogen evolution from CuO(x)-C/TiO(2) with multiple electron transport pathways

Titanium dioxide nanoparticles co-modified with CuO(x) (0≤x≤2) and carbonaceous materials were prepared with a simple hydrolysis and photo-reduction method for photocatalytic hydrogen generation. SEM/TEM and XPS analysis indicated that the carbonaceous materials were mostly coated on the TiO(2) surface and clearly revealed that the Cu species exhibited multivalence states, existing as CuO(x) (0≤x≤2). The optimal catalyst showed a 56-fold enhanced hydrogen evolution rate compared with that of the pure C/TiO(2) catalyst. Further, an intensive multiple electron transfer effect originating from CuO(x) and the carbonaceous materials is proposed to be responsible for the elevated photoactivity. CuO(x) species serve as electron donors facilitating charge carrier transfer and proton reduction sites. The carbonaceous materials function as the “bridge” that transfers the electrons of TiO(2) to the CuO(x) species, which provides a new route for electron transfer and reinforces the effect of CuO(x) as a co-catalyst. In this study, the CuO(x) and C co-modified TiO(2) catalyst was prepared with multiple electron transport pathways and enhanced hydrogen production evolution, which provides a deep understanding for the design of co-catalyst-based photocatalysts.