Efficient removal of TC and CIP antibiotics by surface modified g-C3N4/CdS nanocomposite under sunlight irradiation

Abstract

Aquatic environment organic pollutant removal is very essential for human health. Tetracycline (TC) and Ciprofloxacin (CIP) are most use antibiotics to treat the bacterial infections. These antibiotics are entering into the aquatic system through feces and urine of both humans and animals, thereby increasing the environmental toxicity. Consequently, it is crucial to treat the antibiotics residues from the aquatic environment. Photocatalysis method is considered as a promising way to effectively treat the contaminated aquatic environment. The g-C3N4/CdS was successfully synthesized through a simple hydrothermal method. Various characterization techniques were used to examine the physical and chemical characteristics of the synthesized materials. The g-C3N4/CdS nanocomposite has high surface area 76.12 m2/g, narrow band gap energy 2.26 eV, and less electron-hole recombination. The g-C3N4/CdS photocatalyst shows higher degradation efficiency of TC and CIP as 96.2 and 80% in 40 min under sunlight irradiation. In addition, the radical trapping experiment reveals that h+, •O2− and 1O2 are the key role for the degradation of TC and CIP over g-C3N4/CdS nanocomposite. Moreover, the intermediate by products of TC and CIP were also examined by using GC-MS. This work, facilitates that the construction of g-C3N4/CdS nanocomposite have high capable to remove the toxic substances from the contaminated water under direct sunlight irradiation.