摘要
A novel visible-light-active photocatalyst consisting of CeO 2 nanoparticles and I, K-codoped graphitic carbon nitride (IK-C 3 N 4 ) was engineered using urea, potassium iodate and cerium nitrate as raw materials via a facile pyrolysis method. The CeO 2 /IK-C 3 N 4 composite was then applied for the rapid elimination of acetaminophen (ACT) under 465-nm visible light irradiation in aqueous solutions at different environmental parameters. The electronic images clearly showed that 5 – 20 nm CeO 2 can be tightly attached onto IK-C 3 N 4 . The charge imbalance of Ce element as well as oxygen vacancy of CeO 2 /IK-C 3 N 4 enhanced the photocatalytic activity of the composite. Moreover, the optical property and bandgap were easily tuned by changing the CeO 2 amounts. At optimum composition of 15 wt% CeO 2 , the bandgap of CeO 2 /IK-C 3 N 4 can narrow down to 2.38 eV. The photocatalytic activity of CeO 2 /IK-C 3 N 4 heterojunction toward ACT degradation is dependent on CeO 2 amounts and environmental parameters including pH, anions and initial ACT concentration. The calculated pseudo-first-order rate constants ranged from 0.039 to 0.051 min −1 . The radical species trapping experiments confirmed that O 2 [rad]− and h + play significant roles in ACT degradation. Thus, enhanced photodegradation of ACT is explained by type-II heterojunction mechanism. These findings provide a promising strategy of combining CeO 2 and doped g-C 3 N 4 for the effective removal of emerging pollutants under visible light irradiation, which can open a new route to synthesize novel heterojunction with high photoactivity for water purification and environmental sustainability.