Physical chemical studies of cobalt electrodeposition as a contribution to the understanding of the fundamental steps of electrodeposition

• Grant number: 12/05563-0
• Support Opportunities: Regular Research Grants
• Start date: March 01, 2013
• End date: February 28, 2015
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Physical-Chemistry
• Principal Investigator: Paulo Teng An Sumodjo
• Grantee: Paulo Teng An Sumodjo
• Host Institution: Instituto de Química (IQ). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Besides the usual applications, metals and metallic alloys thin films are used in the electronic and information technology for making miniaturized devices and computer chips and magnetic data storage systems. Co-based magnetic alloys are excellent alternatives to the corresponding Fe alloys in the sense that they are less susceptible to suffer corrosion. Among the many possible ways of thin films synthesis, electrodepositon presents many advantages such as obtention of uniform our nanostructured deposits on surfaces with a complex geometry. Although electrodeposition has been used industrially for over 170 years, many of the fundamentals of the kinetics and mechanisms of the initial elementary steps are still not thoroughly understood. Many authors have recently reported studies covering those aspects for different electrodeposition processes. This is understandably, as knowledge of the initial elementary steps of the electrodeposition process is the key to controlling the growth of the deposits and, therefore, to obtaining deposits with desired morphology and microstructure and consequently, with desired properties. To contribute to knowledge of electrodeposition processes, this proposal has the objective to study the initial steps of the electrochemical deposition of Co in the presence of additives such as glycine and 5-sulfosalicylic acid in the plating bath. Additives, although widely used in electrodeposition, their role in the process has not been rationalized yet. This project proposes to use electrochemical conventional techniques, the FTIR spectroelectrochemistry technique and surface morphology and microstructure analysis ex-situ techniques such as SEM, TEM, AFM and XRD to carry on the proposed study. Furthermore, the many powerful techniques developed to study surfaces, ranging from spectroscopic to scanning probe techniques, have been more recently employed in-situ during electrochemical studies. Thus, it is also planned to study the use of the techniques available at the Laboratório Nacional de Luz Síncroton, LNLS, X-ray absorption spectroscopy (XAS) and surface-ray scattering (SXS), in electrodepostion studies. (AU)