高等学校化学学报 ›› 2018, Vol. 39 ›› Issue (7): 1503.doi: 10.7503/cjcu20170814

• 物理化学 • 上一篇    下一篇

能级可调的钾离子掺杂石墨相氮化碳的可控制备及“双渠道”光催化合成过氧化氢性能

王辉(), 裴彦博, 胡绍争, 马文涛, 石朔宇   

  1. 辽宁石油化工大学化学化工与环境学部, 抚顺 113001
  • 收稿日期:2017-12-13 出版日期:2018-07-10 发布日期:2018-06-22
  • 作者简介:联系人简介: 王 辉, 女, 博士, 讲师, 主要从事催化新材料研究. E-mail: wanghuilnpu@163.com
  • 基金资助:
    国家自然科学基金(批准号: 41571464)和辽宁省教育厅一般项目(批准号: L2014145)资助.

Synthesis and “Two Channel Pathway” Photocatalytic H2O2 Production Ability of Band Gap Tunable K+ Doped Graphitic Carbon Nitride

WANG Hui*(), PEI Yanbo, HU Shaozheng, MA Wentao, SHI Shuoyu   

  1. College of Chemistry, Chemical Engineering, and Environmental Engineering,Liaoning Shihua University, Fushun 113001, China
  • Received:2017-12-13 Online:2018-07-10 Published:2018-06-22
  • Contact: WANG Hui E-mail:wanghuilnpu@163.com
  • Supported by:
    † Supported by the National Natural Science Foundation of China(No.41571464) and the Education Department of Laoning Province, China(No.L2014145).

摘要:

采用共聚合法制备了能级可控的碱金属K+掺杂石墨相氮化碳(g-C3N4)催化剂, 考察了催化剂光催化制取过氧化氢的性能. 采用X射线多晶粉末衍射(XRD)、 N2吸附-脱附等温线、 场发射扫描电子显微镜(SEM)、 紫外-可见吸收光谱(UV-Vis)、 光致发光光谱(PL)、 X射线光电子能谱(XPS)和电化学阻抗谱(EIS)等手段对催化剂进行了表征. 结果表明, K+掺入g-C3N4的晶格间隙, 并且对催化剂的比表面积、 可见光吸收能力及电子-空穴分离效率产生显著影响; 通过控制K+掺杂量可以调控g-C3N4催化剂的能级位置, 从而使光催化合成过氧化氢反应从“单渠道”变成“双渠道”, 显著提高了过氧化氢的平衡浓度.

关键词: 氮化碳, 钾离子掺杂, 能级调控, 光催化, 过氧化氢合成

Abstract:

Band gap tunable K+ doped graphitic carbon nitride was synthesized. Photocatalytic H2O2 production ability of as-prepared catalyst was investigated. X-ray diffraction(XRD), N2 adsorption analysis, scanning electron microscopy(SEM), UV-Vis, photoluminescence(PL) and X-ray photoelectron spectroscopies(XPS) and electrochemical impedance spectrometry(EIS) were used to characterize the obtained catalysts. The results indicate that K+ doping not only promotes the specific surface area(SBET), visible light absorption and separation rate of electron-hole pairs, but tunes the CB and VB positions of as-prepared catalysts by controlling the K+ doping amount. Such tunable band potential results in the photocatalytic H2O2 production from “single channel pathway” to “two channel pathway”. One pathway is that photoelectrons reduce oxygen to generate hydrogen peroxide, the other is that VB holes oxidize OH- to form ·OH, which subsequently react with each other to form hydrogen pero-xide. Such “two channel pathway” leads to the promoted H2O2 production ability. This work provides a new idea of catalyst preparation for photocatalytic hydrogen peroxide production.

Key words: g-C3N4, K+ doping, Band gap tuning, Photocatalysis, H2O2 production

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