{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T05:35:50Z","timestamp":1790573750043,"version":"4.1.0"},"reference-count":51,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2025,11,21]],"date-time":"2025-11-21T00:00:00Z","timestamp":1763683200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100007620","name":"the Educational Department of Liaoning Province","doi-asserted-by":"crossref","award":["JYTMS20231703"],"award-info":[{"award-number":["JYTMS20231703"]}],"id":[{"id":"10.13039\/501100007620","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100007620","name":"the Educational Department of Liaoning Province","doi-asserted-by":"crossref","award":["JYTQN2023427"],"award-info":[{"award-number":["JYTQN2023427"]}],"id":[{"id":"10.13039\/501100007620","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100007620","name":"the Educational Department of Liaoning Province","doi-asserted-by":"crossref","award":["LJKQZ20222291"],"award-info":[{"award-number":["LJKQZ20222291"]}],"id":[{"id":"10.13039\/501100007620","id-type":"DOI","asserted-by":"crossref"}]},{"name":"the Natural Science Foundation of Anshan Normal University","award":["23kyxm027"],"award-info":[{"award-number":["23kyxm027"]}]},{"name":"the Natural Science Foundation of Anshan Normal University","award":["23kyxm031"],"award-info":[{"award-number":["23kyxm031"]}]},{"name":"the Doctoral Scientific Research Foundation of Anshan Normal University","award":["22b11"],"award-info":[{"award-number":["22b11"]}]},{"name":"the Doctoral Scientific Research Foundation of Anshan Normal University","award":["22b12"],"award-info":[{"award-number":["22b12"]}]},{"name":"the Natural Science Foundation of Liaoning Province","award":["2023-BS-173"],"award-info":[{"award-number":["2023-BS-173"]}]},{"name":"Startup Fund of Scientific Research of Dalian Polytechnic University for High-Level Talents"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Inherent conductivity and high redox activity endow polyaniline (PANI) with great potential to serve as a cathode material for aqueous zinc-ion batteries. However, compared with traditional strongly acidic electrolytes (pH &lt; 1), its electrochemical performances are moderated in weakly acidic zinc salt electrolytes (pH &gt; 3) because of spontaneous deprotonation. Herein, a carboxyl-modified PANI was designed and synthesized by introducing carboxyl groups at the para-position of the terminal benzene rings within the polymer chains. In this conjugated system, the electron density in the polymer chains was redistributed with a higher one around the substituent due to the electron-withdrawing effect of carboxyl groups and meanwhile carboxyl groups characterized by a proton donor render PANI achieve a proton-involved electrochemical reaction. Consequently, the carboxyl-modified PANI cathode, in a Zn\/\/PANI cell, delivers an impressive specific capacity of 226 mAh g\u22121 along with excellent rata capability and cycling stability. This work presented some new insights into the molecule structure design of PANI-based polymers applied in advanced aqueous batteries.<\/jats:p>","DOI":"10.3390\/molecules30234498","type":"journal-article","created":{"date-parts":[[2025,11,21]],"date-time":"2025-11-21T11:04:31Z","timestamp":1763723071000},"page":"4498","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["A Carboxyl-Modified Polyaniline Cathode for High-Performance Aqueous Zinc-Ion Batteries"],"prefix":"10.3390","volume":"30","author":[{"ORCID":"https:\/\/orcid.org\/0009-0008-3268-6701","authenticated-orcid":false,"given":"Zhen","family":"Sun","sequence":"first","affiliation":[{"name":"Liaoning Key Laboratory of Development and Utilization for Natural Products Active Molecules, School of Chemistry and Life Science, Anshan Normal University, Anshan 114005, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shijun","family":"Tang","sequence":"additional","affiliation":[{"name":"School of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Haixu","family":"Wang","sequence":"additional","affiliation":[{"name":"Liaoning Key Laboratory of Development and Utilization for Natural Products Active Molecules, School of Chemistry and Life Science, Anshan Normal University, Anshan 114005, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shiyu","family":"Liu","sequence":"additional","affiliation":[{"name":"Hegang Science and Technology Intelligence Research Institute, Hegang 154100, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-2006-1234","authenticated-orcid":false,"given":"Xiang","family":"Cai","sequence":"additional","affiliation":[{"name":"Liaoning Key Laboratory of Development and Utilization for Natural Products Active Molecules, School of Chemistry and Life Science, Anshan Normal University, Anshan 114005, China"},{"name":"School of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,11,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2310393","DOI":"10.1002\/adfm.202310393","article-title":"Advances and Perspectives of Ion-Intercalated Vanadium Oxide Cathodes for High-Performance Aqueous Zinc Ion Battery","volume":"34","author":"Bai","year":"2024","journal-title":"Adv. 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