pH值对水热合成磷酸铋的光催化性能的影响

Effect of pH Value on Photocatalytic Properties of Bismuth Phosphate Synthesized by Hydrothermal Method

利用水热法通过调节溶液的pH值合成了不同物相和形貌的磷酸铋。用X射线衍射仪(XRD)和扫描电子显微镜(SEM)对样品进行了物相和形貌表征,并以10 mg.L-1的亚甲基蓝溶液为目标降解物,对材料的光催化降解性能进行了评价。结果表明:前驱物溶液的pH值对磷酸铋的形貌、物相和光催化性能都有较大影响。前驱物溶液pH值为1.3时制得的磷酸铋的光催化性能最高,室温汞灯照射20 min,亚甲基蓝的降解率可达到99.61%。

The bismuth phosphate nanorods were prepared using Bi（NO3）3 · 5H2O and Na3PO4 · 12H2O as raw materials via a hydrothermal method through adjusting the pH value of precursor solution.The as-prepared samples were characterized by XRD and EM.The photocatalytic properties of samples prepared at different pH values were also evaluated using the photocatalytic oxidation of methylene blue under 300 W mercury lamp irradiation.The results indicated that the pH value has a great effect on the phase composition,morphology and photocatalytic property of bismuth phosphate.The optimum photocatalytic property of the bismuth phosphate powder synthesized at pH=1.3 is found and the decolorization rate of methylene blue reaches 99.61% at 20 min under 300 W mercury lamp irradiation.