Advanced Transmission Electron Microscopy Application in Non-Noble Catalyst Materials for CO2 Hydrogenation

Transmission electron microscopy (TEM) now has become one of the most influential techniques in nanoscience and nanoengineering characterization fields, which can be used to study the structure, component or valence at sub-angstrom scale. We involved the advanced Cs-corrected S/TEM to reveal the microstructural evolution of the non-noble catalyst for carbon dioxide hydrogenation. Firstly, we designed a porous Co@C catalysts derived from a novel layered metal-organic framework (MOF) with tunable pore sizes for CO₂ hydrogenation. Pointing out the dependence of the durability on the pore size. Secondly, we find the partial loss of catalytic activity of non-noble CoFe alloy catalysts, as exposed to oxygen, can be attributed to the migration of Co element from the core region of CoFe alloy to the surface. The adsorption energy of H for CoFe₂O₄ shell is stronger than Fe₃O₄ shell, so it is harder to fully desorb for H in the follow reaction process. Lastly, we revealed the non-noble catalyst structure stability optimization strategies and mechanisms in long-term reaction process for CO₂ hydrogenation. The studies above provide a new viewpoint to design high-performance catalyst and modify their structures.