title: New Insights into CO2 Absorption Mechanisms with Amino-Acid Ionic Liquids.
abstract: The last decade saw an explosion of interest in using amine-functionalized materials for CO2 capture and conversion, and it is of great importance to elucidate the relationship between the molecular structure of amine-functionalized materials and their CO2 capacity. In this work, based on a new quantitative analysis method for the CO2 absorption mechanism of amino-acid ionic liquids (ILs) and quantum chemical calculations, we show that the small difference in the local structure of amine groups in ILs could lead to much different CO2 absorption mechanisms, which provides an opportunity for achieving higher CO2 capacity by structure design. This work revealed that the actual CO2 absorption mechanism by amino-acid ILs goes beyond the apparent CO2 /amine stoichiometry; a rigid ring structure around the amine group in ILs creates a unique electrostatic environment that inhibits the deprotonation of carbamic acid and enables actually equimolar CO2 /amine absorption.
authors.affiliation: Key Laboratory of Biomass Chemical Engineering of Ministry of Education, Colleague of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China.
authors.forename: Qiwei
authors.initials: Q
authors.lastname: Yang
authors.affiliation: Key Laboratory of Biomass Chemical Engineering of Ministry of Education, Colleague of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China.
authors.forename: Zhiping
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Key Laboratory of Biomass Chemical Engineering of Ministry of Education, Colleague of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China.
authors.forename: Zongbi
authors.initials: Z
authors.lastname: Bao
authors.affiliation: Key Laboratory of Biomass Chemical Engineering of Ministry of Education, Colleague of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China.
authors.forename: Zhiguo
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Biomass Chemical Engineering of Ministry of Education, Colleague of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China.
authors.forename: Yiwen
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Key Laboratory of Biomass Chemical Engineering of Ministry of Education, Colleague of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China.
authors.forename: Qilong
authors.initials: Q
authors.lastname: Ren
authors.affiliation: Key Laboratory of Biomass Chemical Engineering of Ministry of Education, Colleague of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China. xinghb@zju.edu.cn.
authors.forename: Huabin
authors.initials: H
authors.lastname: Xing
authors.affiliation: Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, United States.|Department of Chemistry, University of Tennessee, Knoxville, TN, 37966, United States.
authors.forename: Sheng
authors.initials: S
authors.lastname: Dai
mesh_terms: D000596:Amino Acids / Q000737:chemistry*; D002245:Carbon Dioxide / Q000737:chemistry*; D052578:Ionic Liquids / Q000737:chemistry*; D009943:Organophosphorus Compounds / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D000596:Amino Acids; D052578:Ionic Liquids; D009943:Organophosphorus Compounds; D002245:Carbon Dioxide
keywords: absorption; amine; capture; carbon dioxide; ionic liquids