首页> 中文期刊> 《无机材料学报》 >pH对低温燃烧法合成钨酸铋光催化降解罗丹明B的影响

pH对低温燃烧法合成钨酸铋光催化降解罗丹明B的影响

         

摘要

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.%以低温燃烧法制备钨酸铋(LCM-Bi2WO6), 并表征了其晶体结构、形貌特征、等电点及紫外漫反射谱, 同时以染料罗丹明B(RhB)为目标污染物(25 mg/L, pH=4),考察了所制备Bi2WO6的吸附性能和光催化性能,并探讨了RhB溶液pH(1、4、7、10)及酸度调节剂成分(盐酸和硫酸)的影响.结果表明, 所制备Bi2WO6为正交相, 吸收极限波长为455 nm,禁带宽度为2.72 eV,晶格粒径为14.7 nm,等电点为3.43;其对RhB的吸附和光催化效果强于水热法制备Bi2WO6和二氧化钛(TiO2).不同pH溶液中, LCM-Bi2WO6对RhB的吸附过程和光催化过程分别符合准二级动力学方程和一级动力学方程式,且吸附平衡量(7.48~21.93 mg/g)和光催化速率常数(0.0197~0.1181 min-1)均随pH降低而增大.LCM-Bi2WO6对RhB的光催化降解主要由·OH所致.光催化过程中, RhB紫外可见光谱的蓝移现象揭示LCM-Bi2WO6可通过脱乙基-共轭显色基团断裂途径降解RhB.以H2SO4调节酸度时, SO42-离子可被Bi2WO6强吸附,从而使得LCM-Bi2WO6对RhB的平衡吸附量(qe为6.03 mg/g)和光催化速率(kv为0.115 min-1)远小于HCl调节(qe为21.93 mg/g,kv为0.1181 min-1)时对RhB的平衡吸附量和光催化速率.

著录项

  • 来源
    《无机材料学报》 |2015年第5期|535-541|共7页
  • 作者单位

    暨南大学环境学院,广东省高校水土环境毒害性污染物防治与生物修复重点实验室 广州510632;

    暨南大学环境学院,广东省高校水土环境毒害性污染物防治与生物修复重点实验室 广州510632;

    暨南大学生态学系,广州510632;

    暨南大学环境学院,广东省高校水土环境毒害性污染物防治与生物修复重点实验室 广州510632;

    暨南大学环境学院,广东省高校水土环境毒害性污染物防治与生物修复重点实验室 广州510632;

    暨南大学生态学系,广州510632;

    暨南大学环境学院,广东省高校水土环境毒害性污染物防治与生物修复重点实验室 广州510632;

    暨南大学环境学院,广东省高校水土环境毒害性污染物防治与生物修复重点实验室 广州510632;

    暨南大学环境学院,广东省高校水土环境毒害性污染物防治与生物修复重点实验室 广州510632;

    暨南大学生态学系,广州510632;

    暨南大学环境学院,广东省高校水土环境毒害性污染物防治与生物修复重点实验室 广州510632;

    暨南大学生态学系,广州510632;

    暨南大学环境学院,广东省高校水土环境毒害性污染物防治与生物修复重点实验室 广州510632;

    暨南大学生态学系,广州510632;

  • 原文格式 PDF
  • 正文语种 chi
  • 中图分类 腐蚀的控制与防护;
  • 关键词

    低温燃烧法; 钨酸铋; 光催化; pH;

相似文献

  • 中文文献
  • 外文文献
  • 专利
获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号