A graphitic carbon nitride-based efficient nanocomposite: low cost and stupefying photocatalyst for the degradation of tetracycline and As3+ in wastewater†

The paucity of pure water has become a serious concern due to the rapid increase of industrialization and massive population growth. The frequent usage of colorless pollutants in our daily lives leads to an accumulation in water bodies and causes adverse effects when consumed unknowingly. Therefore, it becomes crucial to remove these kinds of pollutants from wastewater. We report a nanocomposite comprising silver (Ag) nanoparticles decorated on graphitic carbon nitride (CN) and employed for visible light-induced photocatalytic removal of tetracycline (TC) and As³⁺ as well as oil–water separation. A simple calcination, acid-etching followed by in situ chemical reduction method was used to fabricate the binary nanocomposite, namely AgECN. The resulting nanostructure showed tremendous potential towards TC degradation and As³⁺ oxidation in a short period of time. It was observed that 92% of TC and 99% of As³⁺ became degraded within 90 minutes using AgECN-3% nanocomposite. In addition, it showed better oil–water separation efficiency. A radical scavenging study demonstrated the involvement of superoxide radical (O₂˙⁻) and photogenerated holes (h⁺) towards TC degradation and As³⁺ oxidation. The synergistic effect of individual components in the nanocomposite exhibited outstanding separation of photogenerated charge carriers proceeding with remarkable photocatalytic activity compared to the individual components alone.