Facile synthesis of CuO/g-C₃N₄ nanolayer composites with superior catalytic reductive degradation behavior

The cupric oxide (CuO) loaded graphitic carbon nitride (g-C₃N₄) nanocomposites (CuO/g-C₃N₄) were prepared by a facile calcination method. The formation of monoclinic CuO nanocrystals along with g-C₃N₄ was confirmed by X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopic analysis. X-ray photoelectron spectral (XPS) analysis further confirms the formation of CuO/g-C₃N₄. Distribution of CuO stone-like crystalline nanoparticles on g-C₃N₄ nanosheets was observed by transmission electron microscopic images. The influence of CuO loading on the optical property of g-C₃N₄ was determined by ultraviolet (UV)-visible absorption and photoluminescence (PL) spectral analysis. Band gap was decreased from 2.7 to 2.3 eV by the addition of CuO nanoparticles. The catalytic performance of the synthesized samples in 4-nitrophenol (4-NP) and methyl orange (MO) reduction was evaluated. The 5 wt% CuO/g-C₃N₄ showed 99.5% (7 min) and 99.7% (4 min) reduction efficiency for 4-NP and MO respectively. The 5 wt% CuO/g-C₃N₄ could become a potential catalyst in the chemical treatment of organic pollutants.