摘要
以钛酸四丁酯为原料,采用水热法合成3种TiO_(2)载体(TiO_(2)-G、TiO_(2)-E和TiO_(2)-H),利用溶胶-固载法将活性组分Au、Pd负载在TiO_(2)载体上制备了3种Au Pd/TiO_(2),采用XRD、XPS、N_(2)吸/脱附等温线、EPR、ICP-AES、TEM和HRTEM对其进行了表征。考察了TiO_(2)不同氧空位含量对Au Pd/TiO_(2)无溶剂催化氧化苯甲醇反应性能的影响。结果表明,Au Pd/TiO_(2)-G具有最高的氧空位含量(0.198)、最小的Au Pd纳米颗粒平均粒径(1.83 nm),其在120℃下催化氧化苯甲醇的反应中表现出最优异的催化性能,转化频率为70554 h^(-1),明显优于Au Pd/TiO_(2)-H(39512 h^(–1))和Au Pd/TiO_(2)-E(14814 h^(–1));Au Pd/TiO_(2)-G具有最低反应表观活化能(55.77 k J/mol),明显低于Au Pd/TiO_(2)-H(72.78 k J/mol)和Au Pd/TiO_(2)-E(82.83 k J/mol)。较高的载体氧空位含量有利于在催化剂表面形成较小尺寸的Au Pd纳米颗粒和较高含量的表面Pd^(0)物种,是Au Pd/TiO_(2)-G在苯甲醇氧化反应中取得优异催化活性的关键。
Three different Au Pd/TiO_(2)catalysts were prepared via sol-immobilization method by loading active components Au and Pd onto the TiO_(2)supports(TiO_(2)-G,TiO_(2)-E and TiO_(2)-H),which were synthesized by using tetrabutyl titanate as raw material through hydrothermal method,and characterized by XRD,XPS,N_(2)adsorption-desorption isotherm,EPR,ICP-AES,TEM and HRTEM.The effect of different oxygen vacancy content in TiO_(2)on the catalytic performance of Au Pd/TiO_(2)for solvent-free oxidation of benzyl alcohol was analyzed.The results showed that Au Pd/TiO_(2)-G,with the highest oxygen vacancy content(0.198)and the smallest sized Au Pd nanoparticles(1.83 nm),exhibited a transformation frequency of 70554h^(–1),significantly better than Au Pd/TiO_(2)-H(39512 h^(–1))and Au Pd/TiO_(2)-E(14814 h^(–1)),and the lowest apparent activation energy(55.77 kJ/mol),obviously lower than Au Pd/TiO_(2)-H(72.78 k J/mol)and Au Pd/TiO_(2)-E(82.83 k J/mol),indicating the best benzyl alcohol catalytic oxidation performance at 120℃.A higher content of oxygen vacancy in the support was conducive to the formation of smaller-sized Au Pd nanoparticles and a higher content of surface Pd^(0) species on the catalyst surface,which was the key in achieving the excellent catalytic activity of Au Pd/TiO_(2)-G in the benzyl alcohol catalytic oxidation reaction.
作者
李冬晨
郭晓宇
王哲
史荣会
赵炜
李晓良
LI Dongchen;GUO Xiaoyu;WANG Zhe;SHI Ronghui;ZHAO Wei;LI Xiaoliang(State Key Laboratory of Clean and Efficient Utilization of Coal-Based Energy,Taiyuan University of Technology,Taiyuan 030024,Shanxi,China;College of Chemical Engineering and Technology,Taiyuan University of Technology,Taiyuan 030024,Shanxi,China;Department of Chemistry and Chemical Engineering,Taiyuan Institute of Technology,Taiyuan 030008,Shanxi,China;College of Ecological Environment and Urban Construction,Fujian University of Technology,Fuzhou 350118,Fujian,China)
出处
《精细化工》
EI
CAS
CSCD
北大核心
2024年第12期2674-2681,共8页
Fine Chemicals
基金
山西省基础研究计划(自由探索类)自然科学研究面上项目(20210302123093)
福建省自然科学基金项目(2023J01931)。
