A novel Ag3PO4-CaO composite photocatalyst with enhanced photocatalytic activity was synthesized and utilized for degradation of ammonia from aqueous solution under sunlight. Ag3PO4 was prepared by pre- cipitation met...A novel Ag3PO4-CaO composite photocatalyst with enhanced photocatalytic activity was synthesized and utilized for degradation of ammonia from aqueous solution under sunlight. Ag3PO4 was prepared by pre- cipitation method, and the composite of AgjPO4-CaO was prepared via impregnation method. Utilization of eggshell for CaO synthesis provided a cost-effective and environmental friendly way for the hetero- geneous catalyst production. The as-prepared photocatalysts were characterized by FT-IR, FE-SEM, TEM, EDX, UV-vis and PL Results show that the Ag3PO4-CaO samples have excellent photocatalytic perfor- mances in the wide visible-light region. The effect of operating parameters like the content of Ag3PO4 in composite, initial ammonia concentration, pH of solution, catalyst dosage and oxygen supply was investi- gated. The photoeatalyst with 60 wt% content of Ag3PO4 had a high photocatalytic performance, because a low content of Ag3PO4 causes weak light absorption, and the excess amount of it results in serious electron-hole recombination due to the aggregation of AgjPO4 particles. The maximum ammonia degra- dation （about 70%） was achieved in 340 mg/L of ammonia, pH 11, and 1.25 g/L of catalyst in the presence of pure oxygen. In comparison to Ag3PO4, 60 wt% AgjPO4-CaO had a good stability and it could have been easily separated from the solution for recycling.展开更多
文摘A novel Ag3PO4-CaO composite photocatalyst with enhanced photocatalytic activity was synthesized and utilized for degradation of ammonia from aqueous solution under sunlight. Ag3PO4 was prepared by pre- cipitation method, and the composite of AgjPO4-CaO was prepared via impregnation method. Utilization of eggshell for CaO synthesis provided a cost-effective and environmental friendly way for the hetero- geneous catalyst production. The as-prepared photocatalysts were characterized by FT-IR, FE-SEM, TEM, EDX, UV-vis and PL Results show that the Ag3PO4-CaO samples have excellent photocatalytic perfor- mances in the wide visible-light region. The effect of operating parameters like the content of Ag3PO4 in composite, initial ammonia concentration, pH of solution, catalyst dosage and oxygen supply was investi- gated. The photoeatalyst with 60 wt% content of Ag3PO4 had a high photocatalytic performance, because a low content of Ag3PO4 causes weak light absorption, and the excess amount of it results in serious electron-hole recombination due to the aggregation of AgjPO4 particles. The maximum ammonia degra- dation （about 70%） was achieved in 340 mg/L of ammonia, pH 11, and 1.25 g/L of catalyst in the presence of pure oxygen. In comparison to Ag3PO4, 60 wt% AgjPO4-CaO had a good stability and it could have been easily separated from the solution for recycling.
