Design a promising nickel oxide embedded graphitic carbon nitride photocatalyst using for fast degradation of Indigo carmine dye
摘要
Cubic nickel oxide (NiO) embedded with graphitic carbon nitride (g-C3N4) nanocomposite, NiO@g-C3N4, serves an effective photocatalyst to the degradation of synthetic blue food dye, Indigo Carmine (IC). The nanocomposite was prepared using a facile thermal polymerization technique followed by an annealing procedure. The as-synthesized nanocomposite’s structures and morphologies were characterized using different techniques. The efficiency of degradation and reaction kinetics were evaluated using UV–visible spectroscopy under sunlight exposure. The catalyst’s degradation rate for IC dye was approximately 99.34% achieved in 19 min under an optimal reaction conditions. The degradation rate was followed a pseudo-first order kinetics of rate constant, k1 = 196.6 × 10–3. Other factors such as catalyst dosage, pH of the medium and degradation in tap water were also performed where the efficiency of NiO@g-C3N4 have been significantly influenced during the photodegradation process. The impact of coexisting anions and cations on the photodegradation efficiency of NiO@C3N4 was additionally evaluated. Trapping agents are introduced to identify the reactive species, and results showed that the super oxide (O2.−) radicals are the main reactive species, whereas .OH, electrons, and h+ holes had a lesser impact on the degradation process. The degradation efficiency of the catalyst in tap water reaches up to 86%. The stability of the nanocomposite was examined through three consecutive catalytic cycles, demonstrating the robustness of the catalyst.