Dynamic catalysts for the production of clean energy

DYCAT研究项目旨在研究催化活性金属(铂和钯)与用作载体的CeO2之间的相互作用。我们最近发现，通过在温和的温度下应用基于短期交替还原/氧化序列的合适的催化剂预处理，可以优化铂的结构和电子性质。这种动态催化剂的概念可以为催化量身定做和稳定高效的纳米颗粒。DYCAT项目的目标是解开这一创新概念，并将其转移到能源生产中的进一步关键催化反应中，例如用于制氢的水-气变换反应和CH4的清洁催化燃烧。在开发高活性催化剂时，主要考虑CeO2的表面性质及其与铂、钯的相互作用。这一科学方法是基于先进的原位/操纵性表征技术、动力学/催化性能和理论模型之间的耦合。具有高时间和空间分辨率的同步加速器技术，如X射线吸收/发射光谱(XAS、ME-XAS、HERFD-XANES或V2C-XES)将被用于获取有关电子态、局部配位环境、与反应物的相互作用以及在所应用的反应条件下贵金属颗粒尺寸变化的信息。在具有高时间分辨率的新一代环境透射电子显微镜(经像差校正)上，将获得关于纳米尺度上活性中心动态变化的补充信息。这两种表征方法之间的协同是至关重要的、非常创新的，并且对法德合作具有明显的附加值。此外，将这些前沿方法与系统的催化测试和理论计算相结合，有望显著提高对贵金属/CeO2界面动力学行为的基本理解，这是操作法形成WGS和CH4氧化反应高效催化剂的先决条件。

The DYCAT research project aims to investigate the interaction between a catalytically active metal (Pt and Pd) and CeO2, used as a support. We have recently found that the structure and electronic properties of platinum can be optimized by applying a suitable catalyst pretreatment based on short-term alternating reducing/oxidizing sequences at mild temperatures. This concept of “dynamic catalysts” can tailor and stabilize efficient nanoparticles for catalysis. The DYCAT project objective is to unravel and transfer this innovative concept to further key catalytic reactions in energy production, such as the water-gas shift reaction for H2 production and the clean catalytic combustion of CH4. For developing highly active catalysts, mainly the CeO2 surface properties and its interaction with Pt and Pd will be considered. The scientific approach is based on the coupling between advanced in-situ/operando characterization techniques, kinetics/catalytic performance and theoretical modelling. Synchrotron based techniques with high time and spatial resolutions like X-ray absorption / emission spectroscopy (XAS, ME-XAS, HERFD-XANES or V2C-XES) will be used to access information on the electronic state, local coordination environment, interaction with reactants and noble metal particle size variation under applied reaction conditions. Complementary information on the dynamic variations of active sites at the nanoscale will be obtained on a new generation of Environmental Transmission Electron Microscope (aberration-corrected) with a high temporal resolution. The synergy between these two families of characterization methods is essential, very innovative, and a clear added value to the Franco-German collaboration. Furthermore, the coupling of these cutting-edge methods with systematic catalytic tests and theoretical calculations is expected to significantly improve the fundamental understanding of the noble metal/ceria interface dynamic behaviour, which is the prerequisite for operando shaping efficient catalysts for WGS and CH4 oxidation reactions.