{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,11]],"date-time":"2026-02-11T11:15:25Z","timestamp":1770808525108,"version":"3.50.0"},"reference-count":41,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,2,9]],"date-time":"2026-02-09T00:00:00Z","timestamp":1770595200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012166","name":"National Key R&D Program of China","doi-asserted-by":"crossref","award":["2022YFE0204100"],"award-info":[{"award-number":["2022YFE0204100"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100006769","name":"Russian Science Foundation","doi-asserted-by":"publisher","award":["25-13-00185"],"award-info":[{"award-number":["25-13-00185"]}],"id":[{"id":"10.13039\/501100006769","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Polymer films of nickel Schiff-base complexes were investigated to clarify degradation mechanisms induced by coordinating impurities\u2014specifically, the protic solvents methanol and isopropanol. Films of poly[Ni(Salen)] and its sterically protected derivatives were electropolymerized in situ and subjected to cyclic voltammetry (CV) and electrochemical quartz crystal microbalance (EQCM) measurements in dry acetonitrile electrolyte with 1% vol. alcohol added. In situ monitoring of redox activity and mass changes revealed something. It was revealed that traces of alcohols act as axial ligands to the Ni center. This disrupts the conjugated \u03c0-system and conductivity of the polymer. The rate of electrochemical stability strongly depends on the complex structure. The unsubstituted poly[Ni(Salen)] film showed the fastest loss of capacity in both methanol and isopropanol, whereas complexes with methyl substituents in the diimine bridge (poly[Ni(Salpn-1,2)] and poly[Ni(Saltmen)]) exhibited significantly improved stability. EQCM measurements revealed irreversible changes in the mass of all polymer films upon exposure to alcohol-containing electrolytes. These observations are consistent with the axial coordination of alcohol molecules to the Ni centers and the concomitant ingress of solvent species into the polymer matrix. The results demonstrate that molecular design\u2014specifically, introducing steric hindrance around the metal center\u2014markedly enhances resistance to coordinating impurities.<\/jats:p>","DOI":"10.3390\/ijms27041685","type":"journal-article","created":{"date-parts":[[2026,2,9]],"date-time":"2026-02-09T16:13:32Z","timestamp":1770653612000},"page":"1685","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Effect of Coordinating Impurities on the Electrochemical Stability of Polymeric Nickel(II) Schiff-Base Complexes"],"prefix":"10.3390","volume":"27","author":[{"given":"Ulyana M.","family":"Rodionova","sequence":"first","affiliation":[{"name":"Institute of Chemistry, Saint-Petersburg University, 199034 Saint-Petersburg, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1989-6236","authenticated-orcid":false,"given":"Daniil A.","family":"Lukyanov","sequence":"additional","affiliation":[{"name":"Institute of Chemistry, Saint-Petersburg University, 199034 Saint-Petersburg, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Peixia","family":"Yang","sequence":"additional","affiliation":[{"name":"MIIT Key Laboratory of Critical Materials, Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ruopeng","family":"Li","sequence":"additional","affiliation":[{"name":"MIIT Key Laboratory of Critical Materials, Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4538-316X","authenticated-orcid":false,"given":"Oleg V.","family":"Levin","sequence":"additional","affiliation":[{"name":"Institute of Chemistry, Saint-Petersburg University, 199034 Saint-Petersburg, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6337-7719","authenticated-orcid":false,"given":"Elena V.","family":"Alekseeva","sequence":"additional","affiliation":[{"name":"Institute of Chemistry, Saint-Petersburg University, 199034 Saint-Petersburg, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"108199","DOI":"10.1016\/j.matdes.2019.108199","article-title":"Review of the use of transition-metal-oxide and conducting polymer-based fibres for high-performance supercapacitors","volume":"186","author":"Azman","year":"2020","journal-title":"Mater. Des."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"012105","DOI":"10.1088\/1757-899X\/561\/1\/012105","article-title":"Supercapacitor technology and its applications: A review","volume":"561","author":"Shetty","year":"2019","journal-title":"IOP Conf. Ser. Mater. Sci. Eng."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1605902","DOI":"10.1002\/adma.201605902","article-title":"Coordination Polymers Derived General Synthesis of Multishelled Mixed Metal-Oxide Particles for Hybrid Supercapacitors","volume":"29","author":"Guan","year":"2017","journal-title":"Adv. Mater."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"281","DOI":"10.1016\/j.jpowsour.2018.09.023","article-title":"Advanced metal-organic frameworks (MOFs) and their derived electrode materials for supercapacitors","volume":"402","author":"Du","year":"2018","journal-title":"J. Power Sources"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"e1602076","DOI":"10.1126\/sciadv.1602076","article-title":"A highly stretchable, transparent, and conductive polymer","volume":"3","author":"Wang","year":"2017","journal-title":"Sci. Adv."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"4218","DOI":"10.1039\/C5CE02510A","article-title":"Smart, stretchable and wearable supercapacitors: Prospects and challenges","volume":"18","author":"Zheng","year":"2016","journal-title":"Cryst. Eng. Comm."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"100520","DOI":"10.1016\/j.mser.2019.100520","article-title":"Polymers for supercapacitors: Boosting the development of the flexible and wearable energy storage","volume":"139","author":"Wang","year":"2020","journal-title":"Mater. Sci. Eng. R. Rep."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"319","DOI":"10.1016\/j.jpowsour.2011.08.112","article-title":"Polypyrrole\/carbon nanotube nanocomposite enhanced the electrochemical capacitance of flexible graphene film for supercapacitors","volume":"197","author":"Lu","year":"2012","journal-title":"J. Power Sources"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"550","DOI":"10.1016\/j.electacta.2014.05.051","article-title":"Synthesis of spherical PANI particles via chemical polymerization in ionic liquid for high-performance supercapacitors","volume":"135","author":"Li","year":"2014","journal-title":"Electrochim. Acta"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"348","DOI":"10.1016\/j.tsf.2015.01.055","article-title":"In-situ polymerization of polyaniline on the surface of graphene oxide for high electrochemical capacitance","volume":"584","author":"Li","year":"2015","journal-title":"Thin Solid Film."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"788","DOI":"10.1002\/pat.1578","article-title":"Organic acid doped polythiophene nanoparticles as electrode material for redox supercapacitors","volume":"22","author":"Gnanakan","year":"2011","journal-title":"Pol. Adv. Tech."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"15987","DOI":"10.1039\/c1jm12986d","article-title":"Compositional effects of PEDOT-PSS\/single walled carbon nanotube films on supercapacitor device performance","volume":"21","author":"Antiohos","year":"2011","journal-title":"J. Mater. Chem."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1392","DOI":"10.1021\/cm902876u","article-title":"Graphene\/Polyaniline Nanofiber Composites as Supercapacitor Electrodes","volume":"22","author":"Zhang","year":"2010","journal-title":"Chem. Mater."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"10923","DOI":"10.1039\/C4TA01245C","article-title":"Flexible, sandwich-like Ag-nanowire\/PEDOT:PSS-nanopillar\/MnO2 high performance supercapacitors","volume":"2","author":"Yu","year":"2014","journal-title":"J. Mater. Chem. A"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1338","DOI":"10.1007\/s11426-012-4585-y","article-title":"Electropolymerization of Ni(salen) on carbon nanotube carrier as a capacitive material by pulse potentiostatic method","volume":"55","author":"Li","year":"2012","journal-title":"Sci. China Chem."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"616","DOI":"10.1016\/j.jcis.2023.06.056","article-title":"Salen-based porous aromatic frameworks with multi-active sites as anode materials for lithium-ion batteries","volume":"648","author":"Wang","year":"2023","journal-title":"J. Colloid Interface Sci."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"9911","DOI":"10.1021\/jp500249t","article-title":"Electrochemical polymerization and energy storage for poly[Ni(salen)] as supercapacitor electrode material","volume":"118","author":"Yan","year":"2014","journal-title":"J. Phys. Chem. C"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.electacta.2012.03.182","article-title":"Electropolymerization and electrochemical performance of Salen-type redox polymer on different carbon supports for supercapacitors","volume":"76","author":"Zhang","year":"2012","journal-title":"Electrochim. Acta"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"3143","DOI":"10.1007\/s11581-018-2472-z","article-title":"Enhanced electrochemical performance of nitrogen-doped graphene and poly[Ni(Salen)] composite electrodes for supercapacitors","volume":"24","author":"Li","year":"2018","journal-title":"Ionics"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"5325","DOI":"10.1021\/acs.jpcc.8b00434","article-title":"Pseudocapacitive Energy Storage in Schiff Base Polymer with Salphen-Type Ligands","volume":"122","author":"Deng","year":"2018","journal-title":"J. Phys. Chem. C"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"427","DOI":"10.5796\/electrochemistry.84.427","article-title":"Effects of potential modes on performances of electrodeposited poly[Ni(Salen)]\/MWCNTs composite as supercapacitor electrode material","volume":"84","author":"Zhu","year":"2016","journal-title":"Electrochemistry"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"525","DOI":"10.1021\/acsami.8b13742","article-title":"Nickel-Salen-Type Polymer as Conducting Agent and Binder for Carbon-Free Cathodes in Lithium-Ion Batteries","volume":"11","author":"Karushev","year":"2019","journal-title":"ACS Appl. Mater. Interfaces"},{"key":"ref_23","first-page":"389","article-title":"Oxidative Electropolymerization of Metal Schiff-Base Complexes","volume":"160","author":"Horwitz","year":"1988","journal-title":"Mol. Cryst. Liq. Cryst."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"2371","DOI":"10.1016\/S0040-4039(00)77617-9","article-title":"Polymer Supported Transition-Metal Complexes for Catalytic Epoxidation of Olefins","volume":"34","author":"De","year":"1993","journal-title":"Tetrahedron Lett."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"6722","DOI":"10.1016\/j.electacta.2008.01.079","article-title":"Preparation and characterization of poly Ni(Salen)(crown receptor)\/multi-walled carbon nanotube composite films","volume":"53","author":"Tedim","year":"2008","journal-title":"Electrochim. Acta"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"218","DOI":"10.1134\/S102319351002014X","article-title":"In situ Electrochemical Microbalance Studies of Polymerization and Redox Processes in Polymeric Complexes of Transition Metals with Schiff Bases","volume":"46","author":"Krasikova","year":"2010","journal-title":"Russ. J. Elchem."},{"key":"ref_27","first-page":"e20210128","article-title":"Schiff-bases for sustainable battery and supercapacitor electrodes","volume":"2","author":"Troschke","year":"2022","journal-title":"Exploration"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1101","DOI":"10.1007\/s11175-005-0188-7","article-title":"Structuring redox polymers poly M(Schiff) (M = Ni, Pd; Schiff = Schiff bases) on a molecular level: Methods and results of an investigation","volume":"41","author":"Rodyagina","year":"2005","journal-title":"Russ. J. Elchem."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"167","DOI":"10.1149\/08701.0167ecst","article-title":"Dependence of Stability of the Polymerizesd Nickel Complexes with Schiff Bases on the Structure of the Ligand Diimine Bridge","volume":"87","author":"Alekseeva","year":"2018","journal-title":"ECS Trans."},{"key":"ref_30","first-page":"697","article-title":"Redox and Conducting Polymers Based on Salen-Type Metal Units-Electrochemical Study and Some Characteristics","volume":"16","author":"Audebert","year":"1992","journal-title":"N. J. Chem."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"269","DOI":"10.1016\/0022-0728(92)80428-7","article-title":"Electrochemical Polymerization of Several Salen-Type Complexes-Kinetic-Studies in the Microsecond Time Range","volume":"338","author":"Audebert","year":"1992","journal-title":"J. Electroanal. Chem."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"11822","DOI":"10.1021\/jp111831y","article-title":"Preparation and Characterization of a Poly Ni(salen)\/Multiwalled Carbon Nanotube Composite by in Situ Electropolymerization as a Capacitive Material","volume":"115","author":"Gao","year":"2011","journal-title":"J. Phys. Chem. C"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"7460","DOI":"10.1021\/la034525r","article-title":"Electrochemical behavior of a new precursor for the design of poly[Ni(Salen)]-based modified electrodes","volume":"19","author":"Santos","year":"2003","journal-title":"Langmuir"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"117310","DOI":"10.1016\/j.jelechem.2023.117310","article-title":"Uncovering the mechanism of water-promoted electrochemical degradation of NiSalen polymers","volume":"935","author":"Alekseeva","year":"2023","journal-title":"J. Electroanal. Chem."},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Novoselova, J.V., Beletskii, E.V., Lukyanov, D.A., Filippova, S.S., Rodionova, U.M., Sizov, V.V., Alekseeva, E.V., and Levin, O.V. (2025). Sterically Induced Enhancement in the Electrochemical Stability of Salen-Type Cathode Materials. Polymers, 17.","DOI":"10.3390\/polym17020178"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"277","DOI":"10.1134\/S1070363218020147","article-title":"Effect of Structure of Polymeric Nickel Complexes with Salen-Type Ligands on the Rate of Their Electroactivity Decay in Solutions of Water-Containing Electrolytes","volume":"88","author":"Ershov","year":"2018","journal-title":"Russ. J. Gen. Chem."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"80","DOI":"10.1016\/j.electacta.2015.07.123","article-title":"Nickel-N,N\u2032-bis(salicylidene)-1,3-propanediamine (Ni-Salpn) film-modified electrodes. Influence of electrodeposition conditions and of electrode material on electrochemical behaviour in aqueous solution","volume":"178","author":"Martin","year":"2015","journal-title":"Electrochim. Acta"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"75","DOI":"10.1016\/j.electacta.2019.05.075","article-title":"Structure-reactivity requirements with respect to nickel-Salen based polymers for enhanced electrochemical stability","volume":"315","author":"Pieta","year":"2019","journal-title":"Electrochim. Acta"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"111","DOI":"10.1016\/j.electacta.2018.02.085","article-title":"A redox conducting polymer of a meso-Ni(II)-SaldMe monomer and its application for a multi-composite supercapacitor","volume":"268","author":"Pieta","year":"2018","journal-title":"Electrochim. Acta"},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"104","DOI":"10.1016\/j.ccr.2019.05.014","article-title":"Metallo(Salen) complexes as versatile building blocks for the fabrication of molecular materials and devices with tuned properties","volume":"394","author":"Freire","year":"2019","journal-title":"Coord. Chem. Rev."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"25159","DOI":"10.1039\/D2TA04847G","article-title":"The impact of residual solvent on catholyte performance in solid-state batteries","volume":"10","author":"Shen","year":"2022","journal-title":"J. Mater. Chem. A"}],"container-title":["International Journal of Molecular Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1422-0067\/27\/4\/1685\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,2,11]],"date-time":"2026-02-11T05:35:35Z","timestamp":1770788135000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1422-0067\/27\/4\/1685"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,2,9]]},"references-count":41,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2026,2]]}},"alternative-id":["ijms27041685"],"URL":"https:\/\/doi.org\/10.3390\/ijms27041685","relation":{},"ISSN":["1422-0067"],"issn-type":[{"value":"1422-0067","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,2,9]]}}}