{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,6]],"date-time":"2026-02-06T03:24:16Z","timestamp":1770348256805,"version":"3.49.0"},"reference-count":18,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2023,2,15]],"date-time":"2023-02-15T00:00:00Z","timestamp":1676419200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Romanian National Authority for Scientific Research","award":["124705"],"award-info":[{"award-number":["124705"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>Previous studies performed on 2-(azulen-1-yldiazenyl)-5-phenyl-1,3,4-thiadiazole (T) showed that T is a ligand with complexing properties towards heavy metals (HMs) in solution and can be attached to electrode surfaces. Films of T were deposited on glassy carbon to obtain chemically modified electrodes (T-CMEs), either through scanning or using controlled potential electrolysis in tetrabutylammonium perchlorate in acetonitrile. They were investigated using cyclic voltammetry (CV), differential pulse voltammetry (DPV), electrochemical impedance spectroscopy (EIS), and spectroelectrochemistry. All methods provided evidence for showing the formation of insulating films, with properties depending on their electropolymerization potential. CV and EIS studies of T-CMEs in tetrabutylammonium perchlorate in acetonitrile as supporting electrolyte, and in the presence of a ferrocene redox probe resulted in a thickness of ~10 \u00b5m, an active surface area about 6 times higher than the geometrical one, and conductivity of about 10\u22126 S\/cm. This characterization performed using voltammetric techniques reveals the symmetry of the reversible anodic and cathodic redox CV peaks for the polymer, while spectroelectrochemistry shows the intensification of the charge transport process through polarons, due to the anodic polarization of the film.<\/jats:p>","DOI":"10.3390\/sym15020514","type":"journal-article","created":{"date-parts":[[2023,2,15]],"date-time":"2023-02-15T03:09:21Z","timestamp":1676430561000},"page":"514","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Electrochemical Studies of Azulene Modified Electrodes"],"prefix":"10.3390","volume":"15","author":[{"given":"Veronica","family":"An\u0103st\u0103soaie","sequence":"first","affiliation":[{"name":"National Institute of Research and Development in Microtechnology\u2014IMT Bucharest, 126A, Erou Iancu Nicolae Street, 077190 Voluntari, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9226-0170","authenticated-orcid":false,"given":"Ovidiu Teodor","family":"Matica","sequence":"additional","affiliation":[{"name":"Faculty of Chemical Engineering and Biotechnologies, University \u201cPolitehnica\u201d of Bucharest, Gheorghe Polizu Str. 1-7, Sector 1, 011061 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Cecilia","family":"Lete","sequence":"additional","affiliation":[{"name":"Institute of Physical Chemistry \u201cIlie Murgulescu\u201d of the Romanian Academy, 202 Splaiul Independentei, 060021 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Raluca","family":"Isopescu","sequence":"additional","affiliation":[{"name":"Faculty of Chemical Engineering and Biotechnologies, University \u201cPolitehnica\u201d of Bucharest, Gheorghe Polizu Str. 1-7, Sector 1, 011061 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6525-9820","authenticated-orcid":false,"given":"Vesna","family":"Miskovic-Stankovic","sequence":"additional","affiliation":[{"name":"Faculty of Ecology and Environmental Protection, University Union-Nikola Tesla, Cara Dusana 62-64, 11158 Belgrade, Serbia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Eleonora-Mihaela","family":"Ungureanu","sequence":"additional","affiliation":[{"name":"Faculty of Chemical Engineering and Biotechnologies, University \u201cPolitehnica\u201d of Bucharest, Gheorghe Polizu Str. 1-7, Sector 1, 011061 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3222","DOI":"10.1021\/ma035335q","article-title":"Stimuli-Responsive Conjugated Copolymers Having Electro-Active Azulene and Bithiophene Units in the Polymer Skeleton: Effect of Protonation and p-Doping on Conducting Properties","volume":"37","author":"Wang","year":"2004","journal-title":"Macromolecules"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"2091","DOI":"10.1002\/1521-3935(20001001)201:15<2091::AID-MACP2091>3.0.CO;2-4","article-title":"Azulene appended cellulose: Synthesis, optical and chiroptical properties, film formation by electrochemical oxidation","volume":"210","author":"Redl","year":"2000","journal-title":"J. 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