TiO_2-Ag_3PO_4光催化剂的制备及其紫外光催化性能

Preparation of TiO_2-Ag_3PO_4 photocatalyst and its photocatalytic activity under UV irradiation

采用化学沉淀法(两步法)制备了TiO_2-Ag_3PO_4复合光催化剂,考察了该光催化剂紫外光催化降解阳离子染料番红花红T(简称ST)的性能。实验结果表明:在TiO_2-Ag_3PO_4投加量0.7 g/L,初始ST质量浓度70 mg/L、不调节溶液pH的条件下,紫外光照射35 min时的ST降解率高达97.9%;TiO_2-Ag_3PO_4复合光催化剂的光催化性能明显优于单一光催化剂Ag_3PO_4和TiO_2,同时也明显优于Ag-AgCl/Ag_3PO_4复合光催化剂;避光条件下反应40 min,TiO_2-Ag_3PO_4对ST的吸附量仅为2.3 mg/g;TiO_2-Ag_3PO_4在室内自然光下也具有一定的光催化活性;TiO_2-Ag_3PO_4的光催化活性在酸性条件下要优于碱性条件;TiO_2-Ag_3PO_4重复使用5次后,其光催化活性无明显下降,稳定性较好。

The TiO2-Ag3PO4 composite photocatalyst was prepared by chemical precipitation method （two-step method）, and its photocatalytic activity under UV light to degradation of safranine T （ST） cationic dye was explored. The experimental results show that： Under the conditions of TiO2-Ag3PO4 dosage 0.7 g/L, initial ST mass concentration 70 mg/L, without pH adjustment and UV irradiation time 35 min, the degradation rate of ST is up to 97.9%; The photocatalytic activity of TiO2-Ag3PO4 is obviously higher than that of single photocatalyst Ag3PO4 and TiO2, and also Ag-AgC1/Ag3PO4 composite photocatalyst; The adsorption capacity of ST is only 2.3 mg/g after dark reaction for 40 min; TiO2-Ag3PO4 also has photocatalytic activity under indoor natural light; The photocatalytic activity of TiO2-Ag3PO4 in acidic condition is better than that in alkaline condition; TiO2-Ag3PO4 is stable with same photocatalytic activity after 5 times of reuse.