CoNi bimetallic alloy cocatalyst-modified TiO2 nanoflowers with enhanced photocatalytic hydrogen evolution

In terms of improving photocatalytic hydrogen production performance, inexpensive and earth-rich cocatalysts have become promising alternatives to precious metals. Herein, a novel CoNi–TiO₂ photocatalyst composed of TiO₂ nanoflowers and CoNi alloy was prepared by hydrothermal and chemical reduction methods. Various characterizations and test results have confirmed that the further improvement of the photocatalytic performance of the CoNi–TiO₂ photocatalyst is mainly due to the fact that the bimetallic CoNi alloy can accelerate charge transfer and inhibit the recombination of photo-induced carriers. The hydrogen production rate of the prepared CoNi–TiO₂ is about 24 times higher than that of the pristine TiO₂, and its hydrogen production rate value can reach 6580.9 μmol g^?1 h^?1, and showing comparable photocatalytic performance to 0.5 wt% Pt–TiO₂. In addition, combined with the characterization results, a probable mechanism for enhanced photocatalytic performance was proposed. This study provides favorable enlightenment for the design of a series of highly efficient non-precious metal TiO₂-based photocatalysts.