Enhanced Separation Efficiency of PtNix/g-C3N4 for Photocatalytic Hydrogen Production

摘要

Bimetallic materials hold promise for improving catalyst activity, yet little is known about the photocatalytic mechanism that these systems undergo during photocatalytic reaction that lead to efficient catalyst. Herein, we synthesized g-C3N4 combined with PtNix, which shows much higher photocatalytic activity than that of pure g-C3N4 and achieves the highest H-2 evolution rate of 8456 mu mol h(-1) g(-1) for 2.5% PtNix/g-C3N4. The excellent photocatalytic activity resulted from the enhanced charge-separation efficiency compared to the pristine g-C3N4, which was proved by surface photovoltage, photoluminescence, and transient photovoltage spectra. Electrochemical impedance spectroscopy in the dark further confirms the ability of charge transfer of 2.5% PtNix/g-C3N4 is superior to that of pure g-C3N4. This effective separation efficiency gives rise to the observed excellent photocatalytic activity. This study not only provides us with an efficient catalyst for water splitting, but opens new avenues for designing and developing platinum-based photocatalysts.