Abstract
In this work, plasmonic Au/SnO2/g-C3N4 (Au/SO/CN) nanocomposites have been successfully synthesized and applied in the H-2 evolution as photocatalysts, which exhibit superior photocatalytic activities and favorable stability without any cocatalyst under visible-light irradiation. The amount-optimized 2Au/6SO/CN nanocomposite capable of producing approximately 770 mol g(-1) h(-1) H-2 gas under > 400 nm light illumination far surpasses the H-2 gas output of SO/CN (130 mol g(-1)), Au/CN (112 mol g(-1) h(-1)), and CN (11 mol g(-1) h(-1)) as a contrast. In addition, the photocatalytic activity of 2Au/6SO/CN maintains unchanged for 5 runs in 5 h. The enhanced photoactivity for H-2 evolution is attributed to the prominently promoted photogenerated charge separation via the excited electron transfer from plasmonic Au (approximate to 520 nm) and CN (470 nm > > 400 nm) to SO, as indicated by the surface photovoltage spectra, photoelectrochemical I-V curves, electrochemical impedance spectra, examination of formed hydroxyl radicals, and photocurrent action spectra. Moreover, the Kelvin probe test indicates that the newly aligned conduction band of SO in the fabricated 2Au/6SO/CN is indispensable to assist developing a proper energy platform for the photocatalytic H-2 evolution. This work distinctly provides a feasible strategy to synthesize highly efficient plasmonic-assisted CN-based photocatalysts utilized for solar fuel production.