The Influence of Benzotriazole and Tolyltriazole on the Copper Electrodeposition on Polycrystalline Platinum from Acidic Chloride Solutions

Abstract

Benzotriazole (BTAH) and tolyltriazole (TTAH) are well known as highly efficient inhibitors for preventing the corrosion of copper and its alloys as well as important additives for Cu plating baths. The attention of most authors in the last decade was focused on the mechanism of anodic processes in the presence of BTAH using various electrochemical and surface techniques. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] Protecting properties of TTAH were investigated in iodide medium. 8,9 It is generally accepted that BTAH impedes corrosion of copper by the formation of a protective film on the surface, which involves precipitation of cuprous ions as highly insoluble Cu(I)-benzotriazole complexes in polymeric form. Very recently, Vogt et al. 17 confirmed the formation of a thick, inhibiting Cu(I)-BTA film on the Cu(100) surface in HCl solutions at potentials more positive than Ϫ0.35 V vs. SCE, using in situ scanning tunneling microscopy (STM) and Fourier-transform infrared (FTIR) techniques. Orientation of BTAH and TTAH on Cu(100) was studied by Walsh et al. 19 by the near-edge X-ray absorption fine structure (NEXAFS) technique. At submonolayer coverage, BTAH was found to adsorb with the molecular plane close to perpendicular to the surface. At multilayer coverage, BTAH was oriented with the molecular plane tilted by approximately 45Њ from the plane of the substrate.Although anodic behavior of metals in the presence of corrosion inhibitors is of primary interest, the influence of the same additives on their electrodeposition is also essential for understanding the inhibition mechanism. However, the influence of BTAH on the copper electrodeposition has received scant attention. To our knowledge, the cathodic deposition of copper in the presence of BTAH was studied only from acidic sulfate solutions. [20][21][22] This paper refers to the cathodic deposition of copper on platinum from chloride solutions with different quantities of BTAH or TTAH. These investigations were undertaken in order to determine the potential range of adsorption/desorption of these compounds on platinum and to gain a deeper understanding of the complicated mechanism of the inhibiting effect on the deposition of copper. The chloride medium was chosen in order to separate the successive electrode reactions which occur in different potential ranges in this medium. This behavior results from an important stabilization of Cu(I) species by formation of relatively strong chloride complexes. 23 Conversely, Cu(II) and chloride ions form only weak complexes. 24 In order to avoid the development of Cu 2 O layer on the electrode surface, the solutions were acidified with HCl to pH 3. It should be stressed that copper electrodeposition from chloride media has remained of interest for a practical reason originating in the feasibility of obtaining dense copper deposits at acceptable current densities. 25 Depending on pH, benzotriazole can exist in aqueous solutions as either protonated cationic species BTAH 2 ϩ , neutral molecule BTAH, or di...

Electrochemical and Quantum Chemical Studies of 1, 2, 3-Benzotriazole as Inhibitor for Copper and Steel in Simulated Tap Water

“…Also, the BTAH is dominantly present at the BTA − ion in the simulated synthetic tap water due to the pH of 8.5 52) so that the complex formation can be generated directly. The protective layer formed by BTAH was mainly consisted of the complex formation.…”

The thiazole and triazole derivatives as inhibitors of metal corrosion: Part II

“…Osim toga, predložena je i adsorpcija i formiranje kompleksa u isto vreme, pri čemu je utvrđeno da dominantan mehanizam zavisi od primenjene koncentracije inhibitora, potencijala i pH vrednosti rastvora [9]. pH vrednost ima uticaj na naelektrisanje benzotriazola u kojem je pretežno zastupljen u rastvoru [10]:…”

Inhibition Effect of 1-Butyl-4-Methylpyridinium Tetrafluoroborate on the Corrosion of Copper in Phosphate Solutions

“…Such pretreatment of the disk was repeated after each voltammetric measurement. Other details were published in [53][54][55][56]. All the surface-area-dependant values are normalized with respect to the geometric surface area of the working electrode.…”