cadmium sulfide-modified carbon nitride/graphite for photocatalytic removal of sulfamethoxazole from aqueous solutions

Background: sulfamethoxazole  (smx), a sulfonamide antibiotic, is frequently detected at high concentrations in surface and drinking water, indicating widespread contamination.methods: in this experimental study, a graphitic carbon nitride (g-c3n4)/cadmium sulfide (cds) nano-composite was synthesized using a co-precipitation method. the crystal structure, morphology, and surface chemistry of the synthesized nanocomposite were characterized using x-ray powder diffraction (xrd), field emission scanning electron microscopy (fe-sem), and energy-dispersive x-ray spectroscopy (edx), respectively. the experiments were conducted under varying conditions, including ph (3–11), nanocatalyst dosage (0.2–1 g/l), contact time (0–120 minutes), and initial smx concentration (5–20 mg/l).results: xrd and sem analyses confirmed the hexagonal structure of cds, with sem images showing well-dispersed nanoparticles and no agglomeration. the distinct peaks in the xrd pattern indicated well-crystallized cds nanoparticles. optimal removal efficiency was achieved at ph 5, with a nanocatalyst dosage of 0.7 g/l, a contact time of 60 minutes, and an smx concentration of 5 mg/l. kinetic studies revealed that the photocatalytic degradation followed first-order kinetics (r2 = 0.9955).conclusion: based on the results and the physical and chemical properties of the synthesized cds-modified carbon nitride nanocomposite, this photocatalytic process offers a promising, effective, and efficient method for the treatment of antibiotic-contaminated wastewater, particularly for removing smx.