{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,4]],"date-time":"2026-06-04T14:16:51Z","timestamp":1780582611518,"version":"3.54.1"},"reference-count":24,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2025,7,2]],"date-time":"2025-07-02T00:00:00Z","timestamp":1751414400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["22308026"],"award-info":[{"award-number":["22308026"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["CSTB2023NSCQ-MSX0609"],"award-info":[{"award-number":["CSTB2023NSCQ-MSX0609"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Beijing Institute of Technology Research Fund Program for Young Scholars","award":["22308026"],"award-info":[{"award-number":["22308026"]}]},{"name":"Beijing Institute of Technology Research Fund Program for Young Scholars","award":["CSTB2023NSCQ-MSX0609"],"award-info":[{"award-number":["CSTB2023NSCQ-MSX0609"]}]},{"name":"Natural Science Foundation of Chongqing, China","award":["22308026"],"award-info":[{"award-number":["22308026"]}]},{"name":"Natural Science Foundation of Chongqing, China","award":["CSTB2023NSCQ-MSX0609"],"award-info":[{"award-number":["CSTB2023NSCQ-MSX0609"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Membranes"],"abstract":"<jats:p>Excessive carbon dioxide (CO2) emissions represent a critical challenge in mitigating global warming, necessitating advanced separation technologies for efficient carbon capture. Silica-based membranes have attracted significant attention due to their exceptional chemical, thermal, and mechanical stability under harsh operating conditions. In this study, we introduce a novel layered hybrid membrane designed based on amine-functionalized silica precursors, where a distinct affinity gradient is engineered by incorporating two types of amine-functionalized materials. The top layer was composed of high-affinity amine species to maximize CO2 sorption, while a sublayer with milder affinity facilitated smooth CO2 diffusion, thereby establishing a continuous solubility gradient across the membrane. A dual approach, combining comprehensive experimental testing and rigorous theoretical modeling, was employed to elucidate the underlying CO2 transport mechanisms. Our results reveal that the hierarchical structure significantly enhances the intrinsic driving force for CO2 permeation, leading to superior separation performance compared to conventional homogeneous facilitated transport membranes. This study not only provides critical insights into the design principles of affinity gradient membranes but also demonstrates their potential for scalable, high-performance CO2 separation in industrial applications.<\/jats:p>","DOI":"10.3390\/membranes15070201","type":"journal-article","created":{"date-parts":[[2025,7,2]],"date-time":"2025-07-02T07:55:43Z","timestamp":1751442943000},"page":"201","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Hierarchical Affinity Engineering in Amine-Functionalized Silica Membranes for Enhanced CO2 Separation: A Combined Experimental and Theoretical Study"],"prefix":"10.3390","volume":"15","author":[{"given":"Zhenghua","family":"Guo","sequence":"first","affiliation":[{"name":"Beijing Key Laboratory of Photoelectronic\/Electrophotonic Conversion Materials, Key Laboratory of Cluster Science, Ministry of Education, Beijing Institute of Technology Chongqing Innovation Center, Advanced Research Institute of Multidisciplinary Science, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qian","family":"Li","sequence":"additional","affiliation":[{"name":"Beijing Key Laboratory of Photoelectronic\/Electrophotonic Conversion Materials, Key Laboratory of Cluster Science, Ministry of Education, Beijing Institute of Technology Chongqing Innovation Center, Advanced Research Institute of Multidisciplinary Science, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kaidi","family":"Guo","sequence":"additional","affiliation":[{"name":"Beijing Key Laboratory of Photoelectronic\/Electrophotonic Conversion Materials, Key Laboratory of Cluster Science, Ministry of Education, Beijing Institute of Technology Chongqing Innovation Center, Advanced Research Institute of Multidisciplinary Science, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China"},{"name":"Beijing Institute of Technology, Zhengzhou Academy of Intelligent Technology, Zhengzhou 450000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9071-6277","authenticated-orcid":false,"given":"Liang","family":"Yu","sequence":"additional","affiliation":[{"name":"Beijing Key Laboratory of Photoelectronic\/Electrophotonic Conversion Materials, Key Laboratory of Cluster Science, Ministry of Education, Beijing Institute of Technology Chongqing Innovation Center, Advanced Research Institute of Multidisciplinary Science, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China"},{"name":"Beijing Institute of Technology, Zhengzhou Academy of Intelligent Technology, Zhengzhou 450000, China"},{"name":"Beijing Institute of Technology, Zhuhai 519088, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,7,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"11","DOI":"10.1016\/j.memsci.2008.12.017","article-title":"Biogas, membranes and carbon dioxide capture","volume":"328","author":"Favre","year":"2009","journal-title":"J. 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