摘要
在石英平板介质阻挡放电(DBD)反应器中,采用氮气(N)低温等离子体改性制备介孔TiO_(2)光催化剂(M-TiO_(2))。借助XRD、TEM、BET、UV-vis DRS和XPS等手段对M-TiO_(2)进行表征分析。结果表明,N等离子体与煅烧相结合的处理方式下制得的M-TiO_(2)较单纯煅烧处理方式具有更优的可见光催化性能。当CTAB/Ti摩尔比为1/3时,三种M-TiO_(2)中M-TiO_(2)(CTP+C)的比表面积最高(238.2m^(2)/g),禁带宽度最窄(2.51e V),O/O最大(35.7%);可见光持续照射240min时,M-TiO_(2)(CTP+C)对甲基橙(MO)的光降解率最高,达90%以上,且循环稳定性良好。N低温等离子体改性过程可有效改善M-TiO_(2)晶粒的分散性,促进Ti向Ti的转化,其可见光催化活性的提高主要归因于氧空位、间隙碳和间隙氮三者的共同作用。活性物种捕获实验和莫特-肖特基曲线测试结果表明,可见光下降解甲基橙的过程中起主要作用的是O_(2)和h^(+)。在此基础上,给出了M-TiO_(2)(CTP+C)可见光催化的机理模型。
Mesoporous TiO_(2)photocatalysts (M-TiO_(2)) were prepared by nitrogen (N) plasma modification in a quartz plate dielectric barrier discharge (DBD) reactor.The M-TiO_(2)were characterized by XRD,TEM,UV-vis DRS,BET and XPS techniques.M-TiO_(2)(CTP+C) and M-TiO_(2)(C+CTP) showed better visible light catalytic performance than M-TiO_(2)(C).When the molar ratio of CTAB/Ti was 1∶3,M-TiO_(2)(CTP+C) had the highest specific surface area (238.2m^(2)/g),the narrowest band gap (2.51eV) and the largest O/O (35.7%).M-TiO_(2)(CTP+C) exhibited better catalytic activity and chemical stability,and the degradation rate of MO reached 90%within 240min of visible-light irradiation.The Nlow temperature plasma modification can effectively improve the dispersion of M-TiO_(2)grains and promote the conversion of Tito Ti.An enhancement of the visible-light catalytic activity of M-TiO_(2)was obtained by the combined effect of oxygen vacancy,interstitial carbon and interstitial nitrogen.The results of active species capture experiment and Mott-Schottky curve showed that O_(2) and h^(+) played a major role in the visible-light degradation of MO.Based on the above observations,the mechanism model of M-TiO_(2)(CTP+C)visible light catalysis was given.
作者
赵文霞
赵玉
柴子茹
张硕
王世欣
焦志杰
ZHAO Wenxia;ZHAO Yu;CHAI Ziru;ZHANG Shuo;WANG Shixin;JIAO Zhijie(College of Environmental Science and Engineering,Hebei University of Science and Technology,Shijiazhuang 050018,Hebei,China;Key Laboratory of Pollution Prevention and Control Biotechnology of Hebei Province,Hebei University of Science and Technology,Shijiazhuang 050018,Hebei,China)
出处
《化工进展》
EI
CAS
CSCD
北大核心
2022年第11期5820-5829,共10页
Chemical Industry and Engineering Progress
基金
国家重点研发计划重点专项(2016YFC0207907)
河北省高等学校科学技术研究项目(QN2021065)
河北省自然科学基金(E2022208038)
河北省高等学校科学技术研究重点项目(ZD2020345)。
