Shape effect of Pt/CeO2 catalysts on the catalytic oxidation of toluene
Shape effect of Pt/CeO2 catalysts on the catalytic oxidation of toluene
复制标题
Pt/CeO2催化剂催化氧化甲苯的形貌效应
DOI：
10.1016/j.cej.2016.08.056
复制
发表时间：
2016-12-15
影响因子：
15.1
通讯作者：
Ye, Daiqi
中科院分区：
文献类型：
--
作者：
Peng, Ruosi;Sun, Xibo;Ye, Daiqi
本文研究了Pt/CeO 2催化剂的形状效应对甲苯催化氧化的影响。分别采用CeO 2纳米棒、纳米颗粒和纳米立方体（主要暴露于{110）、{111）和（100）晶面）通过吸附法吸附具有可调尺寸的Pt纳米颗粒。对甲苯的催化氧化进行了评价。它们的催化性能表现出显着的载体形状依赖性的行为，和Pt/CeO 2-r样品表现出最好的催化活性，由于最好的还原性和最高浓度的表面氧空位。此外，还计算了基于Pt分散度和表面氧空位浓度的两类TOF，结果表明氧化铈表面的氧空位控制着反应速率。此外，原位紫外拉曼光谱表明，活性氧的供应控制着反应速率，表面氧空位起到补充气相活性氧物种和加速氧循环的作用。
The present work elucidated the shape effect of Pt/CeO2 catalysts toward catalytic oxidation of toluene. CeO2 nanorods, nanoparticles, and nanocubes, dominantly exposed {110), {111), and (100) facet, respectively, were employed to immobilize Pt nanoparticles with tunable size by the adsorption method. The catalytic oxidation of toluene was evaluated. Their catalytic performance shows significantly support-shape-dependent behaviour, and the Pt/CeO2-r sample exhibits the best catalytic activity due to the best reducibility and highest concentration of surface oxygen vacancies. Furthermore, two types of TOFs based on the Pt dispersion and the concentration of surface oxygen vacancies were calculated, and the results suggest the oxygen vacancies on ceria surface control the reaction rate. In addition, in situ UV Raman spectroscopy demonstrates that the supply of active oxygen controls the reaction rate and the surface oxygen vacancies play the role to replenish active oxygen species from gaseous phase and accelerate oxygen cycle for the toluene oxidation.