Dynamic catalysts for the production of clean energy

DYCAT研究项目旨在研究催化活性金属（Pt和Pd）与作为载体的CeO2之间的相互作用。我们最近发现，在温和的温度下，基于短期交替还原/氧化序列，采用合适的催化剂预处理可以优化铂的结构和电子性能。这种“动态催化剂”的概念可以定制和稳定高效的纳米颗粒进行催化。DYCAT项目的目标是阐明并将这一创新概念进一步应用于能源生产中的关键催化反应，如氢气生产的水气转换反应和CH4的清洁催化燃烧。对于开发高活性催化剂，主要考虑的是CeO2的表面性质及其与Pt和Pd的相互作用。科学的方法是基于先进的原位/操作表征技术、动力学/催化性能和理论建模之间的耦合。基于同步加速器的高时间和空间分辨率技术，如x射线吸收/发射光谱（XAS, ME-XAS， HERFD-XANES或V2C-XES）将用于获取电子状态，局部配位环境，与反应物的相互作用以及应用反应条件下贵金属粒度变化的信息。纳米尺度上活性位点动态变化的补充信息将在新一代高时间分辨率的环境透射电子显微镜（像差校正）上获得。这两种表征方法之间的协同作用是必不可少的，非常具有创新性，并且对法德合作具有明显的附加价值。此外，将这些前沿方法与系统催化测试和理论计算相结合，有望显著提高对贵金属/铈界面动力学行为的基本认识，这是制备高效WGS和CH4氧化反应的operando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.