Visible light photocatalytic material Ag3PO4 was prepared by precipitation replacement method and characterized by using XRD, UV-Vis and XPS. The photocatalytic activity was evaluated by means of degradation of micro-organic pollutants in water. The photocatalytic mechanism was discussed based on the active species during photocatlytic process and band structure. The results showed that the band gap was about 1.9 eV, Ag+ on the catalyst surface might capture photoelectron e～ and the lower valence band potential of Ag3PO4 All of these would help for Ag3PO4 to separate e‐-h+ pairs generated under visible light irradiation and the formation of reactive species ·OH. After 60 min visible light irradiation, the degradation rate of methyl orange and humic acid with initial concentration of 15 mg·L-1 reached 97% and 82%, respectively, by using 0.6 g·L-1 Ag3PO4 This result is better than that of TiO2-P25 40% and 25% at the same experimental conditions.%采用沉淀置换法制备了可见光光催化剂Ag3PO4,利用XRD、UV-Vis及XPS等对其进行了结构特性分析,以水中微污染有机物的降解评价了Ag3PO4的光催化活性,并通过活性物种及能带结构的分析对催化剂的光催化机理进行了推测.结果表明,Ag3PO4的带隙能约为1.9 eV、催化剂表面存在的Ag+可捕获光生e-、催化剂的价带电位较低,这有利于Ag3PO4在可见光照射下产生的e--h+的分离及活性物种·OH的形成.经60 min可见光光催化反应,15 mg·L-1的甲基橙和腐殖酸的降解率分别达97％和82％,比同等条件下TiO2-P25的降解率还高40％和25％,光催化剂Ag3PO4的用量为0.6 g·L-1.
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