{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T02:36:21Z","timestamp":1760236581806,"version":"build-2065373602"},"reference-count":29,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2021,12,2]],"date-time":"2021-12-02T00:00:00Z","timestamp":1638403200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>Films of 2-(azulen-1-yldiazenyl)-5-phenyl-1,3,4-thiadiazole (T) were successfully deposited on glassy carbon surfaces to prepare chemically modified electrodes (CMEs). Their surface characterization was analyzed by electrochemical impedance spectroscopy (EIS), atomic force microscopy (AFM), and scanning electron microscopy (SEM). This complexing monomer has been deposited through direct electropolymerization in conditions established during the electrochemical characterization of T performed by cyclic voltammetry (CV), differential pulse voltammetry (DPV) and rotating disk electrode voltammetry (RDE). These methods put in evidence the high degree of asymmetry of oxidation and reduction curves, which is due to the irreversible processes occurring at opposite potentials. The film formation was confirmed by ferrocene redox assay probe. The properties of the electrodes modified with T (T-CMEs) were investigated for sensing heavy metal (HM) ions in water solutions, with promising results for Pb(II) among Cd(II), Cu(II), and Hg(II) ions.<\/jats:p>","DOI":"10.3390\/sym13122292","type":"journal-article","created":{"date-parts":[[2021,12,2]],"date-time":"2021-12-02T02:56:14Z","timestamp":1638413774000},"page":"2292","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Surface Characterization of New Azulene-Based CMEs for Sensing"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0009-0000-1377-5620","authenticated-orcid":false,"given":"Veronica","family":"An\u0103st\u0103soaie","sequence":"first","affiliation":[{"name":"Faculty of Applied Chemistry and Materials Science, Doctoral School of Applied Chemistry and Material Science, University \u201cPolitehnica\u201d of Bucharest, Gheorghe Polizu 1-7, Sector 1, 011061 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Cristian","family":"Omocea","sequence":"additional","affiliation":[{"name":"Faculty of Applied Chemistry and Materials Science, Doctoral School of Applied Chemistry and Material Science, University \u201cPolitehnica\u201d of Bucharest, Gheorghe Polizu 1-7, Sector 1, 011061 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Laura-Bianca","family":"Enache","sequence":"additional","affiliation":[{"name":"Faculty of Applied Chemistry and Materials Science, Doctoral School of Applied Chemistry and Material Science, University \u201cPolitehnica\u201d of Bucharest, Gheorghe Polizu 1-7, Sector 1, 011061 Bucharest, Romania"},{"name":"Center for Surface Science and Nanotechnology, University \u201cPolitehnica\u201d of Bucharest, Splaiul Independentei 313, 060042 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1145-2948","authenticated-orcid":false,"given":"Liana","family":"Anic\u0103i","sequence":"additional","affiliation":[{"name":"Center for Surface Science and Nanotechnology, University \u201cPolitehnica\u201d of Bucharest, Splaiul Independentei 313, 060042 Bucharest, Romania"},{"name":"OLV Development SRL, Brasoveni 3, 023613 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Eleonora-Mihaela","family":"Ungureanu","sequence":"additional","affiliation":[{"name":"Faculty of Applied Chemistry and Materials Science, Doctoral School of Applied Chemistry and Material Science, University \u201cPolitehnica\u201d of Bucharest, Gheorghe Polizu 1-7, Sector 1, 011061 Bucharest, Romania"},{"name":"Center for Surface Science and Nanotechnology, University \u201cPolitehnica\u201d of Bucharest, Splaiul Independentei 313, 060042 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jacobus (Koos) Frederick","family":"van Staden","sequence":"additional","affiliation":[{"name":"Laboratory of Electrochemistry and PATLAB, National Institute of Research and Development for Electrochemistry and Condensed Matter, 202 Splaiul Independentei Street, 060021 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8451-8231","authenticated-orcid":false,"given":"Marius","family":"En\u0103chescu","sequence":"additional","affiliation":[{"name":"Center for Surface Science and Nanotechnology, University \u201cPolitehnica\u201d of Bucharest, Splaiul Independentei 313, 060042 Bucharest, Romania"},{"name":"Academy of Romanian Scientists, 54 Spaiul Independentei, 050094 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Rydz, J., \u0160i\u0161kov\u00e1, A., and Eckstein, A.A. 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