20.500.12556/ReVIS-13775 Interactions of azole molecules with copper ions and copper surfaces covered with chemisorbed H, O, Oh or Cl doctoral dissertation Interakcije azolnih molekul z bakrovimi ioni in bakrenimi površinami, prekritimi s kemisorbiranim H, O, OH ali Cl In real environments, copper and other metal surfaces are never clean. Even during active dissolution in corrosion, they are likely to be covered with adsorbed corrosion-relevant species such as O, OH, H, and Cl. To explore the impact of such species on the bonding of imidazole, used herein as an archetypal model of azole corrosion inhibitors on Cu(111), we conducted a systematic computational study based on the Density-Functional Theory. Over 400 diverse adsorption configurations were considered, with close attention paid to the effects of variables such as surface coverage, the type of corrosion-relevant species, and the distance between the imidazole molecule and the corrosion-relevant species. We demonstrate that O and Cl enhance the adsorption bonding of imidazole, while H has almost no effect, and OH either diminishes or has a negligible impact on the imidazole adsorption. The effect of the adsorbed corrosion-relevant species on the imidazole adsorption usually diminishes with the increasing distance between adsorbed species and imidazole, and with decreasing coverage of corrosion-relevant species. We identified three coadsorption effects of O, OH, H, and Cl on the non-dissociative adsorption of imidazole, including hydrogen bond formation, enhancement of the N–Cu bond, and work-function change induced by coadsorbates. We also found that if the coverage of corrosion-relevant species is too high, then the chemisorption of imidazole is prevented either sterically or due to the unavailability of free surface sites. Moreover, our study shows that chemisorbed O and OH species promote deprotonation of azole molecules on the investigated copper surfaces, as exemplified by benzotriazole, imidazole, and Cu(111). The N–H bond cleavage is involved in such deprotonation. By undergoing molecular deprotonation during adsorption, the resulting adsorption states are more stable, which increases the persistence of chemisorbed azole molecules. Our findings demonstrate that deprotonated benzotriazole molecules exhibit stability that is roughly 1 eV higher on O/Cu(111) and OH/Cu(111), compared to an adsorbed intact molecule on bare Cu(111). However, for imidazole, the degree of stabilization is significantly weaker and ranges from 0.1 to 0.5 eV. Further, we investigated the formation of coordination complexes between copper central ions and 19 different N-heterocyclic inhibitor molecules in an aqueous medium, using a cluster/continuum model, which involves a few explicit water molecules and the surrounding water described implicitly. Our results indicate that most of the investigated ligands have the potential to coordinate with Cu(I) and Cu(II) ions, forming stable two- or fourcoordinated complexes, respectively. The thermodynamic stability of these coordination compounds was also evaluated. V naravi baker in druge kovinske površine niso nikoli čiste. Tudi med aktivnim raztapljanjem pri koroziji so verjetno prekrite s korozijsko pomembnimi zvrstmi, kot so O, OH, H in Cl, adsorbiranimi na površini materiala. Da bi raziskali vpliv takšnih zvrsti na vezavo imidazola, ki smo ga uporabili kot arhetipski model azolnih inhibitorjev korozije na Cu(111), smo izvedli sistematično modelno študijo, ki temelji na teoriji gostotnega funkcionala. Upoštevali smo več kot 400 različnih adsorpcijskih konfiguracij, pri čemer smo posebno pozornost namenili vplivu spremenljivk, kot so pokritost površine, vrsta korozijsko pomembnih zvrsti ter razdalja med molekulo imidazola in korozijsko pomembno zvrstjo. Dokazali smo, da O in Cl ojačata adsorpcijo imidazola, medtem ko H skoraj nima učinka, OH pa bodisi oslabi adsorpcijo imidazola bodisi ima zanemarljiv vpliv nanjo. Pokazali smo, da se vpliv adsorbiranih korozijsko pomembnih zvrsti na adsorpcijo imidazola zmanjšuje z večanjem razdalje med adsorbiranimi zvrstmi in imidazolom ter z zmanjševanjem pokritosti korozijsko pomembnih zvrsti. Na podlagi naših raziskav smo izluščili tri učinke, ki jih imajo zvrsti O, OH, H, in Cl na adsorpcijo imidazola. To so: nastanek vodikove vezi, ojačitev vezi N–Cu in spememba izstopnega dela, ki jo povzročijo omenjeni koadsorbati. Pokazali smo, da se imidazol ne more kemisorbirati na Cu(111), če je pokritost s korozijsko pomembnimi vrstami prevelika, bodisi zaradi steričnih preprek bodisi zaradi nerazpoložljivosti prostih mest na površini materiala. Na primeru inhibitorjev benzotriazola in imidazola ter površine Cu(111) ugotavljamo, da kemisorbirana O in OH spodbujata deprotonacijo adsorbiranih azolnih molekul. Deprotonacija vključuje cepljenje vezi N–H pri benzotriazolu in v manjši meri vezi C–H pri imidazolu. Z molekulsko deprotonacijo med adsorpcijo lahko nastanejo stabilnejša adsorpcijska stanja, kar poveča obstojnost kemisorbiranih molekul. Naše ugotovitve kažejo, da je stabilnost deprotonirane molekule benzotriazola na O/Cu(111) in OH/Cu(111) za približno 1 eV višja v primerjavi z adsorbirano molekulo v nespremenjeni osnovni obliki na čisti površini Cu(111). Na primeru imidazola je stopnja stabilizacije bistveno šibkejša in znaša od 0,1 do 0,5 eV. Nadalje smo raziskali nastanek koordinacijskih kompleksov med bakrovimi ioni in 19 različnimi N-heterocikličnimi molekulami inhibitorjev v vodnih medijih z uporabo gručno/ kontinuirnega modela, kjer je nekaj molekul vode opisanih ekplicitno, ostala voda pa je upoštevana implicitno. Naši rezultati kažejo, da večina preučevanih ligandov koordinira z ioni Cu(I) in Cu(II), pri čemer Cu(I) tvori stabilne dvokoordinirane, Cu(II) pa štirikoordinirane komplekse. Ocenili smo tudi termodinamično stabilnost teh koordinacijskih kompleksov. copper corrosion azole corrosion doctoral dissertation baker ioni interakcije azolne molekule korozija doktorska dela disertacije true false false M. Dlouhy Angleški jezik Slovenski jezik Doktorska disertacija 2026-05-06 14:03:14 2026-05-06 14:03:15 2026-05-07 03:18:40 0000-00-00 00:00:00 2023 0 Ljubljana 2023 Ljubljana Besedilo v angl. jeziku; XXIII, 89 f. 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 546.56:620.193(043.3) 153574147 DR_Dlouhy_Matjaz_2023.pdf DR_Dlouhy_Matjaz_2023.pdf 1 2994B36253226BD406E849B51FBF2EDC 2b7709312dc71fd6d3ed5611bce480a27730daaf90550eb1e2a996a8572ffc0d 9482befd-4943-11f1-8a5a-001a4af901a5 https://revis.openscience.si/Dokument.php?lang=slv&id=16647 Mednarodna podiplomska šola Jožefa Stefana 0 0 0