Electrochemical, spectrochemical and electrocatalytic properties of newly synthesized phthalocyanine compounds with 1,1’-thiobis(2-napthol) groups


Arucu S., Orman E. B. , Sağlam M. B. , Özkaya A. R.

1st International Balkan Chemistry Congress, Edirne, Turkey, 17 - 20 September 2018, pp.265

  • Publication Type: Conference Paper / Summary Text
  • City: Edirne
  • Country: Turkey
  • Page Numbers: pp.265

Abstract

Metal-free and metallo phthalocyanine (Pc) compounds involving a conjugated 18-π electron system have technological applicability in many areas due to their superior properties such as high thermal stability, chemical resistance, high coloring property, semi-conductivity, photoconductivity and catalytic activity. While some of these compounds display only Pc ring based reduction-oxidation processes, the others show central metal-based redox processes [1]. While the electrochemical techniques such as cyclic voltammetry and controlled-potential coulometry give important clues for identification of the nature of these processes, i.e., whether these reactions are ligand or metal based, in situ spectroelectrochemical techniques provide additional support for this identification. In this study, the redox properties of a novel group of Pc compounds including 1,1'-Thiobis(2-naphtol) moieties have been investigated in a suitable organic solvent environment with electrochemical techniques such as cyclic voltammetry and square wave voltammetry. In addition, in order to determine the usability of Pc compounds as electrochromic materials, in situspectroelectrochemical and electrocolorimeric measurements were carried out. The compounds exhibited one-electron reversible or quasi -reversible metal and/or ligand based reduction and oxidation processes, associated with the net colour changes. One of the key tasks of current research on fuel cell and metal-air battery applications is the availability of efficient, stable and low cost electrocatalysts that support the reduction of the oxygen molecule by four electrons. Pc complexes are also receiving increasing attention in the field of fuel cells and metal air cells due to their high electrocatalytic activity in oxygen reduction [2]. For this reason, the catalytic performances of the metal Pc compounds in oxygen reduction were also tested by dynamic voltammetry using a rotating ring-disc electrodecouple potentiostat combined system in an environment similar to fuel cell operating conditions. Fig.1. Molecular structure of the phthalocyanine compounds including 1,1'-Thiobis(2-naphtol) groups