Synthesis and Photocatalytic Degradation Performance of g-C_3N_4/CQDs/SAPO-5 Ternary Composite

摘要

Due to the fatal drawback of fast photo-reduced electron-hole pair recombination rate of g-C_3N_4, g-C_3N_4/CQDs/SAPO-5 ternary composite were prepared. Both of carbon quantum dots and SAPO-5 can form heterojunction with g-C_3N_4 to inhibit the recombination. Their properties were characterized by XRD, SEM, FT-IR, DRS and PL. Data of PL shows a much lower photo-reduced electron-hole pair recombination rate of g-C_3N_4/CQDs/SAPO-5. The effect of CQDs amount loaded on ternary composite on the RhB photodegradation performance under visible light was discussed in detail. The observed RhB degradation performances indicate that the order of photocatalytic activity is: g-C_3N_4/CQDs/SAPO-5> g-C_3N_4/ SAPO-5 > g-C_3N_4. g-C_3N_4/CQDs/SAPO-5 with CQDs load ratio of 0.25 w.t.% shows the best photodegradation performance. The highest efficiency is about 24.43% higher than g-C_3N_4/ SAPO-5 and 47.15% higher than pristine g-C_3N_4, respectively. This work is promising for developing novel g-C_3N_4-based photocatalysts for environmental purification.