The lanthanide doping effect on toluene catalytic oxidation over Pt/CeO2 catalyst.
The lanthanide doping effect on toluene catalytic oxidation over Pt/CeO2 catalyst.
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DOI：
10.1016/j.jcis.2022.01.071
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发表时间：
2022-01
影响因子：
9.9
通讯作者：
Ruosi Peng;Haozhi Zhang;Yanjie Guo;Weiqing Huang;You Zhang;Junliang Wu;Mingli Fu;Chenglong Yu-Chenglong-Y
中科院分区：
文献类型：
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作者：
Ruosi Peng;Haozhi Zhang;Yanjie Guo;Weiqing Huang;You Zhang;Junliang Wu;Mingli Fu;Chenglong Yu-Chenglong-Y
本工作旨在了解稀土元素掺杂对Pt/CeO 2催化剂物化性质及其甲苯氧化催化活性的影响。采用水热法将La、Pr、Nd、Sm和Gd等一系列镧系离子引入到CeO 2晶格中，并成功地将相同质量的Pt纳米粒子负载到不同的CeO 2基载体上。它们对甲苯氧化的催化性能表现出显著的镧系元素掺杂效应，且催化活性与掺杂离子的半径和价态密切相关。由于Gd的离子半径较小，价态较低，其掺杂会形成较多的Gd-Ce络合物和较少的GdO 8型络合物，产生较多的氧空位，促进氧的补充。此外，高浓度的氧空位会促使电子从载体转移到金属上，从而得到有利于甲苯吸附和解离的富电子、配位不足的Pt粒子。鉴于上述有利因素，Gd的掺杂可有效提高Pt/CeO 2催化剂对甲苯的催化氧化性能。此外，Pt/CeGdO 2样品具有良好的反应稳定性和抗浓度冲击性。
The present work was undertaken to know the lanthanide doping effect on the physicochemical properties of Pt/CeO2catalysts and their catalytic activity for toluene oxidation. A series of lanthanide ions (La, Pr, Nd, Sm and Gd) were incorporated into ceria lattice by hydrothermal method, and the Pt nanoparticles with equal quality were successfully loaded on various ceria-based supports. Their catalytic performance toward toluene oxidation shows a remarkable lanthanide-doping effect, and the activity is much dependent on the ion radius and valence state of dopants. Owing to smaller ion radius and low valence state, the dopant of Gd would form more Gd-Ce complex and less GdO8-type complex, generating more oxygen vacancies and then promoting oxygen replenishment. Furthermore, the high concentration of oxygen vacancy would drive electrons to transfer from support to metal, and thus electron-rich and under-coordinated Pt particles that are favorable for toluene adsorption and dissociation are obtained. Attributing to above positive factors, the doping of Gd would effectively enhance the catalytic oxidation of toluene over Pt/CeO2catalyst. In addition, the Pt/CeGdO2sample exhibits an excellent reaction stability and resistance of concentration impact.