高表面氧空位浓度的Bi_(2)O_(4)光催化剂的制备及其可见光降解性能研究  

Preparation and visible light degradation performance of Bi_(2)O_(4) photocatalysts with high surface oxygen vacancy concentration

作　　者：王津津 刘宁 伍素云 刘水林 龚升高 唐新德[1] WANG Jinjin;LIU Ning;WU Suyun;LIU Shuilin;GONG Shenggao;TANG Xinde(School of Chemical and Environmental Engineering,Hunan Institute of Technology,Hengyang 421002)

机构地区：[1]湖南工学院,化学与环境工程学院,衡阳421002

出　　处：《环境科学学报》2024年第12期131-142,共12页Acta Scientiae Circumstantiae

基　　金：湖南省自然科学基金(No.2021JJ50084);衡阳市科技计划项目(No.202222015673);湖南省教育厅项目(No.22A0631,21B0797,21C0813);国家自然科学基金(No.22108068)。

摘　　要：表面氧空位(O_(V))浓度在改善缺陷光催化剂的催化性能方面具有重要作用,典型的水热法制备的Bi_(2)O_(4)的表面O_(V)浓度相对较低.如何通过后处理方法提高Bi_(2)O_(4)的表面O_(V)浓度进而提高其可见光催化性能仍然是一个值得研究的问题.本研究通过用HNO_(3)对Bi_(2)O_(4)进行后处理,成功地实现了Bi_(2)O_(4)表面O_(V)浓度的提高.增强的表面O_(V)浓度可捕获更多的光生电子,从而提高Bi_(2)O_(4)的光生电荷分离效率,使得其光催化性能得到提高.HNO_(3)量对处理后的Bi_(2)O_(4)的光降解性能影响较大,在HNO_(3)量为1 m L条件下制备的Bi_(2)O_(4)-1.0对甲基橙(MO)和苯酚具有最佳光降解性能,分别是未处理的Bi_(2)O_(4)的2.42倍和1.46倍.此外,探讨了光催化剂用量、污染物浓度、p H值和无机阴离子对MO和苯酚去除的影响.对于MO的去除,光生空穴(h^(+))和超氧自由基(·O_(2)^(-))被确定为主要的活性物种,而单线态氧(^(1)O_(2))和羟基自由基(·OH)分别被证实为第二和第三重要活性物种.本研究为Bi_(2)O_(4)表面O_(V)浓度的提高从而改善其可见光催化效率提供了一种新的策略.The concentration of surface oxygen vacancies(O_(V))plays an important role in improving the catalytic performance of defective photocatalysts,and the concentration of surface O_(V) of Bi_(2)O_(4) prepared by typical hydrothermal methods is relatively low.How to improve its visible light catalytic performance of Bi_(2)O_(4) via increasing the concentration of surface O_(V) by post-processing methods is still a worthwhile research question.In this study,the concentration of surface O_(V) of Bi_(2)O_(4) was successfully achieved an increase by the post-treatment of Bi_(2)O_(4) with HNO_(3).The enhanced concentration of surface O_(V) captured more photogenerated electrons and thus improved the separation efficiency of photogenerated charges in Bi_(2)O_(4) and improved its photocatalytic performance.The amount of HNO_(3) had a significant impact on the photocatalytic performance of treated Bi_(2)O_(4).When the amount of HNO_(3) was 1 m L,the prepared Bi_(2)O_(4)-1.0 exhibited the best photodegradation performance for methyl orange(MO)and phenol,which was 2.42 times and 1.46 times higher than that of untreated Bi_(2)O_(4),respectively.Moreover,the effects of photocatalyst dosage,pollutant concentration,p H value,and inorganic anion on the removal of MO and phenol were explored.For the removal of MO,photogenerated holes(h^(+))and superoxide radicals(·O_(2)^(-))were identified as the main active species,while singlet oxygen(^(1)O_(2))and hydroxyl radicals(·OH)were confirmed as the second and third important active species,respectively.This work had developed a new strategy for improving the visible light catalytic efficiency of Bi_(2)O_(4) by increasing its surface O_(V).

关 键 词：表面氧空位 Bi_(2)O_(4) HNO_(3) 可见光 降解性能 

分 类 号：O643[理学—物理化学] X703[理学—化学]