Promoted visible-light photocatalytic reduction of Hg2+ over CuAl2O4-decorated g-C3N4 nanoheterojunctions synthesized by solution process

Abstract This work reports an effective effort to indorse the photoreduction of mercury (II) ions (Hg2+) by a developed heterojunction photocatalyst. Nanostructured CuAl2O4-decorated g-C3N4 was synthesized by MCM-41 and F-127 assisted solution process. The CuAl2O4 nanoparticles were dispersed onto g-C3N4 at 1.0, 2.0, 3.0, and 4.0 wt%. The prepared nanostructures were substantiated large surface areas and mesoporous texture surfaces. TEM observation proved the construction of heterojunctions between CuAl2O4 (28.6 nm) and g-C3N4 networks. The photoreduction of Hg2+ over the 3.0 wt% CuAl2O4-decorated g-C3N4 below visible-light radiation was attained with a superior rate of 189.4 µmol min−1 compared to 21.95 µmol min−1 for g-C3N4 and 12.95 µmol min−1 for CuAl2O4. The dose optimization of 3.0% CuAl2O4/g-C3N4. The augmented photocatalytic performance of this novel heterojunction is referred to as confined bandgap and suppression of photogenerated carrier recombination. The sustainable photoreduction of Hg2+ over CuAl2O4/g-C3N4 for five runs was also confirmed the photostability and regeneration ability.