静电纺丝法合成S型异质结CoTiO_(3)/g-C_(3)N_(4)纳米纤维及其增强的可见光光催化活性研究  

Facile electrospinning synthesis of S-scheme heterojunction CoTiO_(3)/g-C_(3)N_(4)nanofiber with enhanced visible light photocatalytic activity

作　　者：杨令坤 李宗军 王鑫 李铃铃 陈哲 Lingkun Yang;Zongjun Li;Xin Wang;Lingling Li;Zhe Chen(School of Material Science and Technology,Jilin Institute of Chemical Technology,Jilin 132022,Jilin,China;State Key Laboratory of High-Efficiency Utilization of Coal and Green Chemical Engineering,National Demonstration Center for Experimental Chemistry Education,College of Chemistry and Chemical Engineering,Ningxia University,Yinchuan 750021,Ningxi1,China)

机构地区：[1]吉林化工学院材料科学与工程学院,吉林吉林132022 [2]宁夏大学化学化工学院,国家实验化学教学示范中心,煤炭高效利用与绿色化工国家重点实验室,宁夏银川750021

出　　处：《Chinese Journal of Catalysis》2024年第4期237-249,共13页催化学报（英文）

基　　金：国家自然科学基金(22278172);吉林省教育厅项目(YDZJ202201ZYTS591);吉林省教育厅项目(20210509049RQ);吉林省教育厅项目(JJKH20230287KJ);青年成长科技项目(20230508144RC);吉林市科技创新发展计划项目(20240103016)。

摘　　要：随着社会的高速发展,化石燃料的消耗量急剧上升,这不仅导致了能源的短缺,而且引发了二氧化碳(CO_(2))及其他有害气体的过量排放,造成环境污染.利用太阳能将CO_(2)光催化转化为碳基燃料是解决上述问题的一种有效途径.在众多半导体光催化材料中,钙钛矿氧化物(CoTiO_(3))由于具有独特的电子和晶体结构以及较好的稳定性而备受关注.然而,由于单一半导体光催化剂中光生电子-空穴对的复合率较高,导致其催化还原CO_(2)的能力有限,制约了其在可见光催化反应中的实际应用.研究发现,构建异质结是提高半导体光催化还原CO_(2)效率的重要策略之一,因此寻找可与CoTiO_(3)能带结构很好匹配的半导体材料至关重要.近年来,有机聚合物g-C_(3)N_(4)因具有独特的层状结构、较好的热稳定性和化学稳定性,对可见光响应性能良好而受到人们的关注.本研究旨在构建g-C_(3)N_(4)与CoTiO_(3)的S型异质结,以优化体系中光生载流子分离效率,从而有效提升光催化性能.本文首先采用静电纺丝法制备出CoTiO_(3)纳米纤维,然后通过一步煅烧法构建CoTiO_(3)/g-C_(3)N_(4)S型异质结光催化剂.X射线衍射仪、傅里叶红外光谱仪、扫描电镜和透射电镜结果证实成功制得了CoTiO_(3)/g-C_(3)N_(4)复合光催化剂.在可见光照射下,测试了不同CoTiO_(3)质量百分含量(0.5%,1%,1.5%,2%和3%,命名为0.5%CTO/CN,1%CTO/CN,1.5%CTO/CN,2%CTO/CN和3%CTO/CN)的CoTiO_(3)/g-C_(3)N_(4)S型异质结光催化剂对CO_(2)的还原能力(反应时间为4 h).结果发现,2%CTO/CN催化剂显示出最高的光催化性能,其催化生成CO和CH4的产率分别为46.5和0.825 mol g^(-1) h^(-1),且生成CO的选择性为98.3%.同时,为了进一步验证光催化性能增强规律,作为补充实验,进行了盐酸四环素(TCH)、土霉素(OTC)和氧氟沙星(OFX)光催化降解实验.结果表明,2%CTO/CN表现出最高的光催化降解效率,2%CTO/CN在光催化CO_(2)�Photocatalysts featuring S-scheme heterojunctions offer considerable potential for both the photocatalytic CO_(2)conversion and the degradation of antibiotics,providing practical solutions for energy crises and environmental challenges.In this work,1D/2D CoTiO_(3)/g-C_(3)N_(4)(CTO/CN)S-scheme heterojunction is synthesized through electrospinning and calcination.The close interweaving of g-C_(3)N_(4)nanosheets around CoTiO_(3)nanofibers creates ample contact areas and active sites,resulting in exceptional photocatalytic CO production capability.The optimal mass ratio of CoTiO_(3)to g-C_(3)N_(4)is 2%,and the CO and CH4 yields are 46.5 and 0.825μmol g^(-1) h^(-1).Moreover,comparing with monomeric g-C_(3)N_(4),this composite achieves a better CO yield with 43.5 times and displays an impressive product selectivity of 98.3%for CO_(2)-CO photoreduction.In addition,the 2%CTO/CN photocatalyst demonstrates outstanding photocatalytic degradation efficiency,with degradation rates of 95.88%,95.53%,and 71.23%for tetracycline hydrochloride,oxytetracycline,and ofloxacin,respectively.These enhanced photocatalytic properties are attributed to the S-scheme system constructed by CoTiO_(3)with g-C_(3)N_(4),maintaining strong oxidation-reduction capabilities while efficiently segregating photogenerated charges,with the existence of S-scheme heterojunction confirmed through various analyses.Furthermore,in situ studies and 13C calibration experiments reveal that CO and CH4 originate from the photocatalytic CO_(2)conversion,further highlighting the potential of this work in advancing CO_(2)photoreduction.This study offers novel insights into designing effective S-scheme heterojunction photocatalysts for practical applications to address environmental and energy challenges.

关 键 词：静电纺丝 S型异质结 g-C_(3)N_(4) 光催化降解 光催化还原CO_(2) 

分 类 号：O643.36[理学—物理化学] O644.1[理学—化学]