Phase-Engineered Robust Cocatalyst of NiFe Bicarbonate with Pt Dopant for Enhanced Photocatalytic Water Splitting.

Exploring efficient cocatalysts capable of accelerating surface catalytic reaction is of great significance for the development of solar-driven hydrogen production. Herein, on the basis of NiFe hydroxide, we developed a series of Pt doped NiFe-based cocatalysts to promote the photocatalytic hydrogen production of graphitic carbon nitride (g-C3N4). We find that the Pt doping can trigger phase reconstruction of NiFe hydroxide and lead to the formation of NiFe bicarbonate, which displays higher catalytic activity toward hydrogen evolution reaction (HER). The Pt doped NiFe bicarbonate modified g-C3N4 shows excellent photocatalytic activity with H2 evolution rate up to 100 μmol/h, which is more than 300 times that of pristine g-C3N4. The experimental and calculation results demonstrate that the greatly improved photocatalytic HER activity of g-C3N4 is not only due to the efficient carrier separation, but also attributed to the accelerated HER kinetics. Our work may provide guidance for designing novel and superior photocatalysts.