Improving the reducibility of CeO2/TiO2 by high-temperature redox treatment: the key role of atomically thin CeO2 surface layers,Journal of Materials Chemistry A

当前位置： X-MOL 学术 › J. Mater. Chem. A › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Improving the reducibility of CeO2/TiO2 by high-temperature redox treatment: the key role of atomically thin CeO2 surface layers
Journal of Materials Chemistry A ( IF 10.7 ) Pub Date : 2022-06-09 , DOI: 10.1039/d1ta08348a
Ramón Manzorro ₁ , José M. Montes-Monroy ₁ , D. Goma-Jiménez ₁ , José J. Calvino ₁ , José A. Pérez-Omil ₁ , S. Trasobares ₁

Affiliation

CeO₂/TiO₂ catalysts treated in reaction environment at high temperatures evolve into complex and diverse systems, where several mixed oxides are formed. To analyze the redox behavior of this system, multiple oxidations and reducing thermal treatments have been applied. Results from the temperature-programmed reduction studies revealed a clear shift at lower temperatures on the reduction peak when the sample was previously reduced at high temperatures and oxidized under mild conditions. Meanwhile, the reduction peak was moved to high temperatures when the sample was previously reduced and oxidized at severe temperatures. The study, which was aimed at correlating this behavior with its chemical structure, was conducted using advanced electron microscopy, including high-resolution TEM and STEM imaging and spectroscopic techniques such as X-EDS and EELS. The data presented here comparing structures at the atomic level and chemical properties have uniquely unveiled that besides the cerium–titanium mixed oxides, a very thin layer up to a single monolayer was deposited along the TiO₂ surface, which indeed was responsible for the improvement of the reducing temperature.

中文翻译：

通过高温氧化还原处理提高 CeO2/TiO2 的还原性：原子级薄 CeO2 表面层的关键作用

CeO ₂ /TiO ₂在高温反应环境中处理的催化剂演变成复杂多样的体系，其中形成了几种混合氧化物。为了分析该系统的氧化还原行为，已经应用了多次氧化和还原热处理。程序升温还原研究的结果表明，当样品先前在高温下还原并在温和条件下氧化时，还原峰在较低温度下会发生明显变化。同时，当样品先前在严酷温度下被还原和氧化时，还原峰移至高温。该研究旨在将这种行为与其化学结构相关联，使用先进的电子显微镜进行研究，包括高分辨率 TEM 和 STEM 成像以及 X-EDS 和 EELS 等光谱技术。₂表面，这确实是提高还原温度的原因。

更新日期：2022-06-09

点击分享查看原文

点击收藏

公开下载

阅读更多本刊最新论文本刊介绍/投稿指南11