A facile strategy for photocatalytic degradation of seven neonicotinoids over sulfur and oxygen co-doped carbon nitride

Abstract

Mounting evidence highlights the negative impacts of neonicotinoids on non-target organisms and ecosystem, yet there are a few of methods to address the residual neonicotinoids in environment. Herein, series of sulfur and oxygen co-doped carbon nitride (SOCNx) were successfully synthesized via one-step thermal polymerization and applied in photodegradation of multi-neonicotinoids (dinotefuran, acetamiprid, clothianidin, thiacloprid, imidacloprid, nitenpyram and thiamethoxam) simultaneously for the first time. Unique tubular structure was observed at the specific doping ratio, which enhanced both mass transfer and specific surface area of graphitic carbon nitride (g-C3N4). The doping process changed the morphology of g-C3N4 materials and also affected its photocatalytic performance. The degradation rate of optimized material (SOCN8) for nitenpyram could surpass 90% just in 30 min under visible light in aqueous matrix. The degradation for target insecticide increased maximum efficiency of 57.6% compared to bulk g-C3N4. Moreover, the possible mechanism of the degradation process was proposed. The results revealed that photon-induced hole (h+) was the primary active species during the degradation of seven investigated neonicotinoids. Moreover, the SOCN8 showed excellent recyclability after four consecutive cycles, which implied promising applications for pesticide-contaminated water remedy.