棱形十二面体Ag_3PO_4微晶的辅助合成及其可见光催化性能

以六次甲基四胺(HMTA)和聚乙烯吡咯烷酮(PVP)为混合辅助剂,采用沉淀法合成了立方晶相棱形十二面体Ag3PO4微晶,对其进行了表征,并通过降解罗丹明B考察了其可见光催化活性。实验结果表明:以0.10g(25 g/mol(以Ag NO3计))HMTA和0.10 g PVP为混合辅助剂合成的棱形十二面体Ag3PO4微晶,其禁带宽度为2.17e V,对罗丹明B有较好的可见光催化活性;在8 mg/L罗丹明B溶液中加入0.4 g/L Ag3PO4,可见光照射12 min时,未添加辅助剂以及分别添加0.10 g PVP、0.10 g HMTA、0.10 g HMTA和0.10 g PVP混合辅助剂制备的Ag3PO4对罗丹明B的降解率分别为67.59%,76.25%,91.88%,99.64%;棱形十二面体Ag3PO4微晶重复使用4次后,罗丹明B的降解率仍达91.59%,说明该光催化剂具有较好的重复使用性能。

Assisted synthesis of rhombic dodecahedron Ag3PO4 microcrystal and its photocatalytic activity under visible light irradiation

Rhombic dodecahedron Ag3PO4 microcrystal was synthesized by precipitation method with mixed assistant of hexametylenteramine(HMTA) and polyvinyl pyrrolidone(PVP). The Ag3PO4 was characterized and its photocatalytic activity under visible light irradiation was evaluated by rhodamine B(RhB) degradation. The experimental results show that:The rhombic dodecahedron Ag3PO4 microcrystal prepared with mixed assistant of 0.10 g(25 g/mol(to AgNO3)) HMTA and 0.10 g PVP has a forbidden band of 2.17 eV and good visible-light photocatalytic activity to RhB;When 8 mg/L rhodamine B(RhB) solution is added with 0.4 g/L Ag3PO4,which is prepared without assistant,with assistant of 0.10 g PVP,0.10 g HMTA,and with the mixed assistant of 0.10 g HMTA and 0.10 g PVP respectively,and under visible light irradiation for 12 min,the degradation rates of RhB are 67.59%,76.25%,91.88% and 99.64% respectively;The degradation rate of RhB on the 4-time reused rhombic dodecahedron Ag3PO4 microcrystal is still 91.59%,it means the photocatalyst has good reusability.