In-situ Fabrication of Ru/C3N4 Nanosheets Mott-Schottky Photocatalyst for Enhanced Photocatalytic H2 Evolution

Abstract

Herein, we developed a strategy for preparing Ru/C3N4 nanosheets with mott-schottky junction, denoted as C3N4-Ru-x. Tris(2,2-bipyridyl)ruthenium(II) chloride hexahydrate (Ru(bpy)3Cl2) was used as a catalyst to promote the thermal exfoliation of bulk g-C3N4 under 680 0C for 5 min in air. As a consequence, g-C3N4 nanosheets with mesoporous were formed and metal Ru was in-situ anchored on g-C3N4 nanosheets. X-ray diffraction verified the effect of the Ru(bpy)3Cl2 on promoting exfoliation of bulk g-C3N4. TEM directly demonstrated g-C3N4 nanosheets with mesoporous were formed and the metal Ru was about 2.5 nm. XPS confirmed the formation of a schottky junction between Ru and g-C3N4 nanosheets. The sample of C3N4-Ru-2.0 with a loading amount of Ru (0.52%) showed a photocatalytic H2 production activity of 42.8 μmol/h. The linear sweep voltammetry (LSV) curve and electrochemical impedance spectroscopy (EIS) showed C3N4-Ru-2.0 had a lower hydrogen evolution overpotential and a smaller charge transfer resistance than C3N4-Ru-0, verifying the promotion effect of Ru on hydrogen evolution of C3N4 nanosheets.