A [Ni(cyclam)]2+-functionalised poly(3,4-ethylenedioxythiophene): Synthesis, electropolymerisation and characterisation of the polymer by cyclic voltammetry and in situ reflectance FTIR spectroscopy

A 1,4,8,11-tetraazacyclotetradecane (cyclam) derivative of 3,4-ethylenedioxythiophene (EDOT) has been synthesised. Its square planar Ni(II) tetrafluoroborate complex has been electrochemically polymerised, with EDOT itself, to give a highly stable conducting polymer with covalently attached [Ni(cyclam)]2+ moieties. The cyclic voltammogram shows redox behaviour typical of a functionalised PEDOT, with the reversible Ni(II)–Ni(III) process of the [Ni(cyclam)]2+ complex superimposed. Reflectance in situ FTIR spectroscopy (RIFTIRS) shows that the presence of the metal complex has a profound influence upon the behaviour of the electronic band of the oxidised form of the polymer, and of the vibrational signature due to the charge carriers.

Graphical abstractA redox-active poly-3,4-ethylenedioxythiophene derivative bearing covalently attached [Ni(cyclam)]2+ (cyclam = 1,4,8,11-tetraazacyclotetradecane) moieties has been electrochemically deposited upon Pt working electrodes. The PEDOT polymer and the Ni complex are reversibly redox-active; the Ni(II)/Ni(III) redox couple is a function of the available co-ligands (coordinating solvent; anions).Figure optionsDownload full-size imageDownload as PowerPoint slide