催化学报 ›› 2020, Vol. 41 ›› Issue (10): 1603-1612.DOI: 10.1016/S1872-2067(19)63496-0

• 论文 • 上一篇    下一篇

金属Bi原位修饰具有(110)暴露面和表面氧空位的BiOBr以增强太阳光催化降解气相正己烷

余晴晴a, 陈江耀a,b, 李彦旭a, 温美成a, 刘宏利a,b, 李桂英a,b, 安太成a   

  1. a 广东工业大学环境健康与污染控制研究院, 环境科学与工程学院, 广东省环境催化与健康风险控制重点实验室, 广州市环境催化与污染控制重点实验室, 广东广州 510006;
    b 汕头广工大协同创新研究院, 广东汕头 515041
  • 收稿日期:2020-02-28 修回日期:2020-03-23 出版日期:2020-10-18 发布日期:2020-08-15
  • 通讯作者: 陈江耀
  • 基金资助:
    国家自然科学基金(21777032,41425015);广东省珠江人才计划本土创新科研团队项目(2017BT01Z032);广东省教育厅创新团队项目(2017KCXTD012).

In-situ decoration of metallic Bi on BiOBr with exposed (110) facets and surface oxygen vacancy for enhanced solar light photocatalytic degradation of gaseous n-hexane

Qingqing Yua, Jiangyao Chena,b, Yanxu Lia, Meicheng Wena, Hongli Liua,b, Guiying Lia,b, Taicheng Ana   

  1. a Guangzhou Key Laboratory Environmental Catalysis and Pollution Control, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, School of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, Guangdong, China;
    b Synergy Innovation Institute of GDUT, Shantou 515041, Guangdong, China
  • Received:2020-02-28 Revised:2020-03-23 Online:2020-10-18 Published:2020-08-15
  • Supported by:
    This work was supported by the National Natural Science Foundation of China (21777032 and 41425015), the Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program (2017BT01Z032), and The Innovation Team Project of Guangdong Provincial Department of Education, China (2017KCXTD012).

摘要: 烷烃是石油化工行业排放的一类重要的人为污染物.烷烃排放到大气后,很容易与大气中的活性物质发生反应,转化为复杂的臭氧和有机气溶胶等二次污染物.而这些二次污染物对大气环境和人类的负面影响更为显著.因此,有效地消除排放源中的烷烃以实现对大气环境和人类健康的保护是迫切需要的.近些年来,基于太阳光和Bi基半导体的光催化降解气相污染物受到了研究人员的广泛关注.然而,目前有关光催化在气相直链烷烃净化中的应用仍然很少.本文采用溶剂法合成了一系列Bi/BiOBr复合材料,并将其应用于太阳光催化降解典型的气相直链烷烃正己烷.XRD,SEM和TEM表征结果表明,反应溶剂中官能团数量的增加(从甲醇、乙二醇到甘油)和溶剂热温度的提高(从160,180到200℃)均有助于实现具有(110)暴露面的BiOBr纳米板上金属Bi纳米球的原位修饰.同时Raman和XPS表征结果表明,Bi与BiOBr在(110)暴露面上形成了化学键,进而导致表面氧空位形成.在实验室自制的光催化反应器中研究了Bi/BiOBr复合材料的太阳光催化降解正己烷性能.120min的降解反应结果表明,适量金属Bi原位修饰有利于促进BiOBr对正己烷的太阳光催化降解性能(初始浓度为15ppmv的正己烷去除效率最高达97.4%).进一步结合UV-Vis,EPR,光电流和PL的表征结果发现,适量Bi原位修饰BiOBr后复合材料表现出更高的可见光响应、更窄的带隙、更大的光电流、更低的电荷载流子复合率以及更强的·O2-和h+形成,最终实现高的光催化性能.本文的结论可有效拓宽Bi基光催化技术在净化石油化工行业排放的气体直链污染物中的应用.

关键词: Bi/BiOBr复合材料, (110)暴露面, 表面氧空位, 太阳光催化, 气相烷烃降解

Abstract: Photocatalytic degradation of gaseous pollutants on Bi-based semiconductors under solar light irradiation has attracted significant attention. However, their application in gaseous straight-chain alkane purification is still rare. Here, a series of Bi/BiOBr composites were solvothermally synthesized and applied in solar-light-driven photocatalytic degradation of gaseous n-hexane. The characterization results revealed that both increasing number of functional groups of alcohol solvent (from methanol and ethylene glycol to glycerol) and solvothermal temperature (from 160 and 180 to 200℃) facilitated the in-situ formation of metallic Bi nanospheres on BiOBr nanoplates with exposed (110) facets. Meanwhile, chemical bonding between Bi and BiOBr was observed on these exposed facets that resulted in the formation of surface oxygen vacancy. Furthermore, the synergistic effect of optimum surface oxygen vacancy on exposed (110) facets led to a high visible light response, narrow band gap, great photocurrent, low recombination rate of the charge carriers, and strong·O2- and h+ formation, all of which resulted in the highest removal efficiency of 97.4% within 120 min of 15 ppmv of n-hexane on Bi/BiOBr. Our findings efficiently broaden the application of Bi-based photocatalysis technology in the purification of gaseous straight-chain pollutants emitted by the petrochemical industry.

Key words: Bi/BiOBr composite, Exposed (110) facet, surface oxygen vacancy, Solar light photocatalysis, Degradation of gaseous alkane