Dalian Institute of Chemistry has achieved new progress in nano-catalytic catalytic theory

Recently, researchers at the State Key Laboratory of Catalysis of Dalian Institute of Chemical Physics, Chinese Academy of Sciences Xiao Jianping, Pan Xiulian, and Academician of the Chinese Academy of Sciences Bao Xinhe have made new progress in the research of nano-confined catalytic theory based on carbon nanotubes. Related results were recently published by the American Chemical Society. (J. Am. Chem. Soc. 2015, 137, 477−482) was published and selected as a spotlight article (J. Am. Chem. Soc. 2015, 137, 1-1).

The team's experimental study found that the nano-tubes of carbon nanotubes composed of curved graphene sheets can lead to changes in the characteristics of the metal nanoparticles assembled inside, and may change the molecular adsorption activation mode or even the reaction pathway, and thus adjust the Catalytic Performance (PNAS 2013, 100, 14861; Angew. Chem. Int. Ed. 2013, 52, 317; Energy Environ. Sci. 2011, 4, 4500; J. Am. Chem. Soc. 2008, 130, (9414; Nat. Mater. 2007, 6, 507, etc.). Based on this, he first proposed the new concept of “cooperative confinement catalysis” for carbon nanotubes (ChemComm., 2008, 6271-6281, Acc. Chem. Res. 2011, 44, 553). In recent years, the team has further adopted the Density Functional Theory (Density Functional Theory) and combined it with experiments to study the limited effect of carbon nanotubes on a series of transition metal Fe, FeCo, RhMn, Ru and other electronic structures and their catalysis. The regularity and nature of the performance modulation function, the concept of the limited-range energy proposed can be used to predict the modulating effects of confined domains on the performance of catalytic reactions.

The results show that the unique electronic structure of the nanospace forms a unique limited microenvironment, leading to the downward movement of the d-band center of the confined metal, weakening the dissociative adsorption of molecules such as CO, N2, and O2, leading to catalysis The volcano-type curve of the reaction shifts in the direction of high binding energy, and the degree of shift is related to the metal species and the diameter of the carbon nanotubes. The results of this study verified the limited range effect of the experimentally observed on the redox properties of the restricted metal, and the different modulation laws of the reactions of CO hydrogenation, NH3 decomposition and ammonia synthesis, and provided important for the design of high-efficiency nanocatalysts in the future. Scientific reference.

The above research has been funded by the National Natural Science Foundation of China, the Ministry of Science and Technology, and the pilot project of the Chinese Academy of Sciences.