水热反应条件对SnO_(2)/Bi_(2)WO_(6)复合材料光催化活性的影响

Effect of hydrothermal reaction conditions on photocatalytic activity of SnO_(2)/Bi_(2)WO_(6) composites

本文以不同水热条件制备了正交晶系结构的两种二氧化锡和一种钨酸铋,并制备出了两种由纳米片组成的花状团簇的二氧化锡/钨酸铋复合光催化材料。通过X射线衍射仪、扫描电子显微镜、比表面积孔隙度测试仪、紫外可见分光光度计等手段对三种样品的样貌、比表面积、孔隙度、孔体积及吸光度测试表征。用碘钨灯来模拟太阳光,研究对比以不同水热条件下制备的钨酸铋以及两种二氧化锡/钨酸铋复合材料作催化剂催化降解罗丹明B的光催化性能。综合实验数据分析,发现二氧化锡/钨酸铋复合样品的衍射峰与钨酸铋样品的衍射峰一致,不同的水热条件会影响产物的物相结构,但对晶体结构和结晶度无影响。光催化360 min时,水热条件为180℃、12 h的钨酸铋对罗丹明B的降解率是33%、水热条件为180℃、6 h的二氧化锡和180℃、12 h的钨酸铋制备的复合物样品1对罗丹明B的降解率是46%、水热条件为180℃、12 h的二氧化锡和180℃、12 h的钨酸铋制备的复合物样品2对罗丹明B的降解率是57%。二氧化锡/钨酸铋复合样品的催化效果优于纯钨酸铋,同时也说明不同水热反应条件对复合光催化材料的催化性能有一定的影响。

In this paper,two kinds of SnO_(2)and one kind of Bi_(2)WO_(6)with orthorhombic crystal system structure were prepared under different hydrothermal conditions,and two kinds of SnO_(2)/Bi_(2)WO_(6)composite photocatalytic materials consisting of flower-like clusters of nanosheets were prepared.The three samples were characterized by X-ray diffractometer,scanning electron microscope,specific surface area porosity tester,and UV-visible spectrophotometer for sample appearance,specific surface area,porosity,pore volume and absorbance tests.A tungsten iodine lamp was used to simulate sunlight to study and compare the photocatalytic performance of Bi_(2)WO_(6)prepared under different hydrothermal conditions and two SnO_(2)/Bi_(2)WO_(6)composites as catalysts for the catalytic degradation of Rhodamine B.The photocatalytic performance of the three samples was analyzed by a UV-visible spectrophotometer.Comprehensive analysis of the experimental data showed that the diffraction peaks of the tin dioxide/bismuth tungstate composite samples were consistent with those of the bismuth tungstate samples,and that the different hydrothermal conditions affected the physical structure of the products but had no effect on the crystal structure and crystallinity.At 360 min of photocatalysis,the degradation rate of rhodamine B was 33%for Bi_(2)WO_(6)at 180℃for 12 h under hydrothermal conditions,46 h for complex sample 1 prepared by SnO_(2)/Bi_(2)WO_(6)at 180℃for 6 h and 180℃for 12 h under hydrothermal conditions,and 57%for complex sample 2 prepared by SnO_(2)/Bi_(2)WO_(6)at 180℃for 12 h and 180℃for 12 h under hydrothermal conditions.The catalytic effect of the SnO_(2)/Bi_(2)WO_(6)composite samples was better than that of pure Bi_(2)WO_(6),which also indicated that the different hydrothermal reaction conditions had a certain effect on the catalytic performance of the composite photocatalytic materials.