Disclosing Ce-In synergy and VO dynamic by XAS/XRD study on MOF-derived In2O3/CeZrOx catalyst for CO2-to-CH3OH conversion

In the race towards CO2 emission reduction, its conversion to methanol is of great interest due to the latter market potential as valuable chemical. Oxide-supported metal catalysts have been widely applied in methanol synthesis and extensively studied for decades. To improve control over the dispersion of catalytic active sites, we have developed a strategy involving thermal decomposition of metal-supported Ce/Zr-based Metal-Organic Frameworks (MOFs) to prepare In2O3 catalyst supported on different CeO2-ZrO2 solid solutions. We here propose to combine quasi-simultaneous XAS/PXRD measurements under reaction relevant conditions (10 bar of CO2:H2 (1:3), 573K) at BM23 to disclose the activation/deactivation mechanisms related to In and Ce reduction and particles agglomeration. Moreover, to track active and transient active species kinetics, we will apply Modulated Excitation of reactants on isolated XAS and PXRD experiments which we successfully already employed previously.

在全球推进二氧化碳减排的进程中，将二氧化碳转化为甲醇因其作为高价值化学品的广阔市场前景而备受关注。氧化物负载型金属催化剂已被广泛应用于甲醇合成领域，并在数十年来得到了深入研究。为实现对催化活性位点分散性的精准调控，我们开发了一种通过热分解负载金属的铈/锆基金属有机框架（Metal-Organic Frameworks, MOFs）的策略，用于制备负载于不同CeO₂-ZrO₂固溶体上的氧化铟（In₂O₃）催化剂。我们提出将在BM23光束线站的反应工况条件（10 bar，CO₂与H₂体积比为1:3，573 K）下，开展准同步X射线吸收光谱（X-ray Absorption Spectroscopy, XAS）/粉末X射线衍射（Powder X-ray Diffraction, PXRD）联合测量，以揭示与铟、铈还原及颗粒团聚相关的催化剂活化与失活机制。此外，为追踪活性物种与瞬态活性物种的动力学演化过程，我们将在独立开展的XAS与PXRD实验中应用反应物调制激发技术——该技术已在我们此前的研究中成功应用。