Quantifying Microenvironment Effect on Metal Electronic Structure With Experimentally Accessible Descriptor: Examples of MOF‐Incorporated Pt Catalysts
Abstract
ABSTRACT The chemical microenvironment surrounding metal nanoparticles (NPs) plays crucial roles in regulating their electronic structures. However, due to the lack of quantitative descriptor, such effect has been understood largely in a qualitative manner. To address this issue, a series of reticular metal‐organic frameworks (MOFs) with diverse functional groups (MIP‐206‐X, X = OH, OCH 3 , H, Cl, and F) were synthesized, and Pt NPs with similar sizes and loadings were incorporated to afford Pt@MIP‐206‐X for ammonia borane methanolysis. X‐ray absorption near edge structure (XANES) was adopted to determine the d‐orbital occupancy of Pt, and the electronic contribution from MOFs was quantified as the descriptor Δe , which was demonstrated to accurately describe the Pt‐methanol adsorption strength (quantified by activation entropy and methanol desorption temperature) and exhibit an excellent linear correlation with catalytic activity. Isotopic analyses and DFT calculations revealed that a larger Δe strengthens methanol adsorption on Pt, promotes O─H bond cleavage as the rate‐determining step (RDS), and leads to enhanced activity.
Article Details
Authors (9)
Weidong Zhang
Department of Materials Science and Engineering
Jiajia Huang
Hefei National Research Center for Physical Sciences at the Microscale, Department of Chemistry, University of Science and Technology of China
Ruichao Xu
National Synchrotron Radiation Laboratory University of Science and Technology of China Hefei P. R. China
Wentao Han
Fang Zongxi Center for Marine Evo-Devo and MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, China.
Mingyang Shen
Hefei National Research Center for Physical Sciences At the Microscale, Department of Chemistry University of Science and Technology of China Anhui P. R. China
Zhongyuan Lin
Hefei National Research Center for Physical Sciences at the Microscale, Department of Chemistry, University of Science and Technology of China
Jing‐Yao Liu
Institute of Theoretical Chemistry College of Chemistry Jilin University Changchun Jilin P. R. China
Zhihu Sun
National Synchrotron Radiation Laboratory, University of Science and Technology of China
Hai‐Long Jiang
Hefei National Research Center for Physical Sciences At the Microscale, Department of Chemistry University of Science and Technology of China Anhui P. R. China