Graphitic carbon nitride-supported iron oxides: High-performance photocatalysts for the visible-light-driven degradation of 4-nitrophenol

Abstract

Abstract Graphitic carbon nitride and its supported iron oxide (x wt% Fe2O3/g-C3N4, x = 0.1–0.8) photocatalysts were fabricated using the guanidine hydrochloride calcination and incipient wetness impregnation methods, respectively. The x wt% Fe2O3/g-C3N4 photocatalysts contained a two-dimensional nanosheet structure with high dispersion of Fe2O3 nanoparticles (2–3 nm in size), a surface area of 27–29 m2/g, and a bandgap energy of 1.92–2.68 eV. The 0.5 wt% Fe2O3/g-C3N4 sample showed the highest photocatalytic activity (90% 4-nitrophenol (4-NP) was degraded within 40 min of visible-light illumination). Effects of pH value, H2O2 amount, and initial 4-NP concentration on activity of the typical sample were also examined. It is concluded that the enhanced photocatalytic activity of 0.5 wt% Fe2O3/g-C3N4 was associated with its unique two-dimensional layered structure, Fe2O3-g-C3N4 heterojunction, high surface oxygen adsorbed species concentration, and easy transfer and separation of photogenerated charge carriers.