Ce0.6Zr0.3Y0.1O2 nanorod supported gold and palladium alloy nanoparticles: high-performance catalysts for toluene oxidation
Ce0.6Zr0.3Y0.1O2 nanorod supported gold and palladium alloy nanoparticles: high-performance catalysts for toluene oxidation
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Ce0.6Zr0.3Y0.1O2纳米棒负载金钯合金纳米颗粒：高性能甲苯氧化催化剂
DOI：
10.1039/c5nr00614g
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发表时间：
2015
期刊：
影响因子：
6.7
通讯作者：
Dai Hongxing
中科院分区：
文献类型：
--
作者：
Tan Wei;Deng Jiguang;Xie Shaohua;Yang Huanggen;Jiang Yang;Guo Guangsheng;Dai Hongxing
采用十六烷基三甲基溴化铵辅助水热还原法和聚乙烯醇保护还原法分别制备了Ce0.6Zr0.3Y0.1O2（CZY）纳米棒及其负载的金钯合金（zZrPdy/CZY; z = 0.80- 0.93wt%; x或y = 0，1，2）纳米粒子（NPs）。通过多种分析技术表征了样品的物理化学性质，并评价了它们对甲苯氧化的催化活性。结果表明，在zirconium Pdy/CZY中的CZY是立方晶体结构，CZY和zirconium Pdy/CZY的表面积在68-77 m2 g-1的范围内，并且具有4.6-5.6 nm尺寸的Au-Pd纳米颗粒高度分散在CZY纳米棒的表面上。在所有样品中，0.90Au1Pd2/CZY具有最高的吸附氧浓度和最好的低温还原性，并且表现最好：在20 000 mL（g h）−1的空速下，T50%和T90%（达到50%和90%的甲苯转化率所需的温度）分别为190和218 °C。 由于水蒸气的引入导致的部分失活是可逆的。活性位点可以是CZY上的表面氧空位、氧化的贵金属NPs和/或贵金属NPs与CZY之间的界面。在0.90- 0.93 μ Pdy/CZY催化剂上甲苯氧化的表观活化能（37-43 kJ mol−1）远低于CZY催化剂上甲苯氧化的表观活化能（88 kJ mol −1）。结果表明，0.90Au1Pd2/CZY的优异催化性能与其高的吸附氧物种浓度、良好的低温还原性、Au-Pd纳米颗粒与CZY纳米棒之间的强相互作用以及Au-Pd纳米颗粒良好的分散性有关。
The Ce0.6Zr0.3Y0.1O2 (CZY) nanorods and their supported gold and palladium alloy (zAuxPdy/CZY; z = 0.80–0.93 wt%; x or y = 0, 1, 2) nanoparticles (NPs) were prepared using the cetyltrimethyl ammonium bromide-assisted hydrothermal and polyvinyl alcohol-protected reduction methods, respectively. Physicochemical properties of the samples were characterized by means of numerous analytical techniques, and their catalytic activities were evaluated for the oxidation of toluene. It is shown that the CZY in zAuxPdy/CZY was cubic in crystal structure, surface areas of CZY and zAuxPdy/CZY were in the range 68–77 m2 g−1, and the Au–Pd NPs with a size of 4.6–5.6 nm were highly dispersed on the surface of CZY nanorods. Among all the samples, 0.90Au1Pd2/CZY possessed the highest adsorbed oxygen concentration and the best low-temperature reducibility, and performed the best: T50% and T90% (temperatures required for achieving toluene conversions of 50 and 90%) were 190 and 218 °C at a space velocity of 20 000 mL (g h)−1, respectively. The partial deactivation due to water vapor introduction was reversible. The active sites might be the surface oxygen vacancies on CZY, oxidized noble metal NPs, and/or interfaces between noble metal NPs and CZY. The apparent activation energies (37–43 kJ mol−1) obtained over 0.90–0.93AuxPdy/CZY were much lower than that (88 kJ mol−1) obtained over CZY for toluene oxidation. It is concluded that the excellent catalytic performance of 0.90Au1Pd2/CZY was associated with its high adsorbed oxygen species concentration, good low-temperature reducibility, and strong interaction between Au–Pd NPs and CZY nanorods as well as good dispersion of Au–Pd NPs.