无机材料学报2015，Vol.30Issue(5)：535-541,7.DOI:10.15541/jim20140503
pH对低温燃烧法合成钨酸铋光催化降解罗丹明B的影响
Effects of Solution pH on Photocatalytic Degradation of Rhodamine B Using Bismuth Tungstate Prepared by Low-temperature Combustion Method
摘要
Abstract
Bismuth tungstate (Bi2WO6) was synthesized by low-temperature combustion method (LCM) and charac-terized by diffuse reflectance spectroscope (DRS), X-ray diffraction (XRD), scanning electron microscope (SEM) and Zeta potential. The effects of solution pH and acidity regulator types on the photocatalytic degradation of RhB by LCM-Bi2WO6 were investigated. Results showed that LCM-Bi2WO6 was an orthorhombic crystal and its wavelength of maximum absorption, forbid bandwidth, lattice size and isoelectric point were 455 nm, 2.72 eV, 14.7 nm and 3.43, respectively. Stronger adsorption and photodegradation of RhB (25 mg/L, pH=4) using LCM-Bi2WO6as photocatalyst was observed, compared with using TiO2 or Bi2WO6 prepared by hydrothermal method as photocatalyst. Adsorption and photodegradation of RhB by LCM-Bi2WO6satisfied the pseudo-second-order kinetic equations and first order ki-netic equations, respectively. Equilibrated adsorption capacity (7.48-21.93 mg/g) and photodegradation rate constants (0.0197-0.1181 min-1) of RhB by LCM-Bi2WO6 were positively related to solution pH. Photocatalytic degradation of RhB by LCM-Bi2WO6 was mainly triggered by free hydroxyl groups (·OH). Blue shifts of RhB ultraviolet-visible spectrum indicated its degradation through ethyl removal and conjugated groups break pathway. Weaker adsorption (qe=6.03 mg/g) and photodegradation (kv=0.115 min-1) of RhB by LCM-Bi2WO6using H2SO4 as acidity regulator were observed compared with using HCl (qe=21.93 mg/g,kv=0.115 min-1) as acidity regulator, because of SO42-strong ad-sorption to LCM-Bi2WO6.关键词
低温燃烧法/钨酸铋/光催化/pHKey words
low-temperature combustion method/Bi2WO6/photocatalysis/pH value分类
矿业与冶金引用本文复制引用
余忠雄,向垒,钟方龙,李彦文,莫测辉,蔡全英,黄献培,吴小莲,赵海明..pH对低温燃烧法合成钨酸铋光催化降解罗丹明B的影响[J].无机材料学报,2015,30(5):535-541,7.基金项目
国家自然科学基金(41173101, 41301337) （41173101, 41301337）
广东省自然科学基金重点项目(2011020003196) （2011020003196）
广东省高校高层次人才项目 （）
东莞市科技计划项目(2012108102043) National Natural Science Foundation of China (41173101, 41301337) （2012108102043）
National Natural Science Foundation of Guangdong Province(2011020003196) （2011020003196）
High-Leveled Talents Project of Guangdong Province's University （）
Scien-tific Research Program of Dongguan (2012108102043) （2012108102043）
