CdS纳米棒/含Ni多钨氧酸盐光催化苯硫酚氧化偶联耦合制氢  

Near-unity photocatalytic dehydrocoupling of thiophenols into disulfides and hydrogen using coupled CdS Nanorods and Ni-containing polyoxometalate

作　　者：任梦真 刘天府 董媛媛 李正 杨嘉新 刁振恒 吕红金 杨国昱 Mengzhen Ren;Tianfu Liu;Yuanyuan Dong;Zheng Li;Jiaxin Yang;Zhenheng Diao;Hongjin Lv;Guo-Yu Yang(MOE Key Laboratory of Cluster Science,Beijing Key Laboratory of Photoelectric/Electrophotonic Conversion Materials,School of Chemistry and Chemical Engineering,Beijing Institute of Technology,Beijing 102488,China;School of Chemical Engineering,Changchun University of Technology,Changchun 130012,Jilin,China)

机构地区：[1]北京理工大学化学与化工学院,原子分子簇科学教育部重点实验室,光电转换材料北京市重点实验室,北京102488 [2]长春工业大学化学工程学院,吉林长春130012

出　　处：《Chinese Journal of Catalysis》2024年第6期312-321,共10页催化学报（英文）

基　　金：国家自然科学基金(21871025,21831001,21706080);国家海外高层次人才引进计划青年项目;北理工高层次人才科研启动计划项目.

摘　　要：二硫化物是生物和药学有机分子合成的重要中间体,并已广泛用于蛋白质功能化、药物传递系统和智能材料等领域.然而,在传统的合成策略中,常使用昂贵或者有毒的有机氧化剂,这不仅增加了合成成本并造成环境污染,而且合成过程中容易出现选择性差、过度氧化等问题.光催化硫醇/硫酚氧化偶联生成二硫化物是一种环境友好的生产路线,但存在催化活性低以及光生载流子不完全利用等问题.因此,开发一种环境友好、成本低廉以及光生电子-空穴高效利用的光催化体系,用于催化硫醇/硫酚氧化偶联并耦合制氢,具有重要的基础研究意义和潜在应用价值.本文构筑了一种Ni_(4)P_(2)/CdS耦合光催化体系,该耦合体系由硫化镉纳米棒(CdS NRs)和含镍的多钨酸盐(Na_(6)K_(4)[Ni_(4)(H_(2)O)_(2)(PW_(9)O_(34))_(2)]·32H_(2)O,简称Ni_(4)P_(2))组成.在光催化氧化4-甲氧基苯硫酚(4-MTP)偶联生成二硫化物的同时,能够释放出氢气,并展现出较好的反应活性.反应4 h后,4-MTP的转化率高达98.39%,二硫化物的选择性为95.0%,二硫化物的收率达24.45μmol,H_(2)的收率为25.96μmol.该耦合体系还展现出了良好的普适性,以–NH_(2),–C_(2)H_(5),–CH_(3),–Cl和–F作为取代基,取代4-甲氧基苯硫酚中的甲氧基并作为底物进行反应,生成相应二硫化物的选择性均超过97%.透射电子显微镜(TEM)和高分辨率X射线光电子能谱(XPS)结果表明,CdS NRs在反应前后形貌保持不变,稳定性较好.X射线光电子能谱表征发现,反应后的CdS NRs表面没有检测到Ni元素的XPS信号峰,说明Ni_(4)P_(2)催化剂附着在CdS NRs的表面,并且能够在反应过程中保持分子的完整性.红外光谱进一步证实了析氢催化剂Ni_(4)P_(2)催化剂的稳定性.此外,荧光光谱、寿命衰减以及光电流测试等系列实验结果表明,CdS NRs与Ni_(4)P_(2)之间存在协同作用,Ni_(4)P_(2)的存在明显地促进光生电子-空穴对Simultaneously harnessing the photogenerated electrons and holes to convert thiols into the value-added disulfides with the concomitant formation of H_(2)represents a highly promising strategy for maximizing the conversion of solar energy into chemical energy.Herein,we report an effective catalytic system comprising CdS nanorods(NRs)and Ni-containing polyoxometalate(Na_(6)K_(4)[Ni_(4)(H_(2)O)_(2)(PW_(9)O_(34))_(2)](Ni_(4)P_(2)))(Ni_(4)P_(2)/CdS),which exhibited efficient photocatalytic activities towards the near-unity dehydrocoupling of 4-methoxythiophenol(4-MTP)into disulfide and H_(2)evolution.The photooxidative dehydrocoupling of 4-MTP can be finished after 4 h photocatalysis,leading to 98.39%conversion of 4-MTP with the yield of disulfide and H_(2)reaching 24.45 and 25.96μmol,respectively.The Ni_(4)P_(2)/CdS catalytic system also showed good photocatalytic recycling stability.Comprehensive experimental and characterization results indicated that the synergistic cooperation between CdS NRs and Ni_(4)P_(2)facilitated the separation and migration of the photogenerated electron-hole pairs,thereby improving the photocatalytic dehydrocoupling of 4-MTP to disulfide coupling with hydrogen production.

关 键 词：脱氢偶联 多金属氧酸盐 硫化镉 析氢 光催化 

分 类 号：TQ116.2[化学工程—无机化工] O643.36[理学—物理化学] O644.1[理学—化学]