Preparation of porous C doped g-C3N4 nanosheets controlled by acetamide for photocatalytic H2 evolution

Abstract

Photocatalytic production H2 of splitting water is an important branch of the application of photocatalytic materials. In this paper, porous C doped carbon nitride was successfully synthesized by calcining urea and acetamide at high temperature, and then analyzed by various characterization methods. XRD and FT-IR spectra show that the crystal structure of carbon nitride modified by acetamide are similar to bulk carbon nitride. SEM and TEM spectra show that the morphology and structure of carbon nitride and carbon nitride was modified by acetamide, which presents a porous nanosheets structure. XPS and EDS show that the content of carbon element in carbon nitride modified by acetamide increased significantly. The PL spectrum is obviously red shift, and the light absorption range is obviously enlarged, which is consistent with the absorption edge of UV–vis Spectrum. The BET of the optimized sample CN2-6 is 122.79 m2g-1, which is 3.04 times higher than that of bulk carbon nitride CN1 (40.456 m2g-1). In addition, the hydrogen production of CN2-6 is 13169.04 μmol/g/h under 300 W Xenon lamp, which is 14.95 times more than CN1 (880.82 μmol/g/h) hydrogen production rate. When the light source is a 10 W LED lamp, the apparent quantum efficiency (AQE) of sample CN2-6 reaches the maximum (2.91) under the wavelengths of 430 nm, which is 1.27 times more than CN1 under the same conditions. Meanwhile, prepared samples have excellent stability and durability under visible light.