1 Thiazole derivatives as corrosion inhibitors for copper Gy. Vastag*, E. Szőcs, A. Shaban, E. Kálmán Chemical Research Center, HAS, Bp., H-1525, P. O. Box 17, Hungary *University of Novi Sad, Faculty of Natural Sciences and Mathematics, Yu. ABSTRACT In-situ information at nanometer levels on corrosion and inhibition processes can be obtained by different methods. During this investigation, we applied electrochemical measurements, in-situ electrochemical scanning probe microscopy (SPM combination with electrochemical quartz crystal microbalance (EQCM) measurements. Those methods are very useful due to their high sensitivity and excellent resolution. Potentiostatic polarization experiments were conducted in order to evaluate the inhibition effectiveness of the additives. The determination of the effectiveness of several potential inhibitors at acidic media was focused on. The aggressive solution was 0.1 M Na 2 SO 4 . The investigated thiazole derivative functional groups contain heterocyclic atoms such and oxygen. 5-benzylidene-2,4-dioxo tetrahydro-1,3- thiazole (BDT) 5-(4 ’ -isopropylbenzylidene)-2,4-dioxotetrahydro-1,3-thiazole (IPBDT), 5-(3 ’ - thenylidene)-2,4-dioxotetrahydro-1,3-thiazole (TDT) and 5-(3 ’ ,4 ’ -dimetoxybenzylidene)-2,4- dioxotetrahydro-1,3-thiazole (MBDT) were tested for copper corrosion inhibition properties. The inhibitor effectiveness was monitored and corrosion rates were determined. The presence of the isopropyl group in the case of IPBDT produced far better protection against copper corrosion in acidic sulfate containing media than the rest of the derivatives. IPBDT was very effective due to the adsorption through the sulfur atom and the longer chain served as an umbrella forming a mono or sub-mono layer on the electrode surface. Dynamic EC-STM and AFM measurements on Cu single crystal electrode with and without the addition of some inhibitors were performed. KEY WORDS: copper corrosion, inhibition, quartz crystal microbalance, AFM, STM.