Electrochromic Properties of a Metallo-supramolecular Polymer Derived from Tetra(2-pyridyl-1,4-pyrazine) Ligands Integrated in Thin Multilayer Films

CLÓVIS DA SILVA; MARCIO VIDOTTI; PABLO A. FIORITO; SUSANA I. CÓRDOBA DE TORRESI; ROBERTO M. TORRESI

LANGMUIR

AMER CHEMICAL SOC

Lugar: Washington; Año: 2012 vol. 28 p. 3332 - 3337

0743-7463

The electrochromic behavior of iron complexes derived from tetra-2-pyridyl-1,4-pyrazine (TPPZ) and a hexacyanoferrate species in polyelectrolytic multilayer adsorbed films is described for the first time. This complex macromolecule was deposited onto indium?tin oxide (ITO) substrates via self-assembly, and the morphology of the modified electrodes was studied using atomic force microscopy (AFM), which indicated that the hybrid film containing the polyelectrolyte multilayer and the iron complex was highly homogeneous and was approximately 50 nm thick. The modified electrodes exhibited excellent electrochromic behavior with both intense and persistent coloration as well as a chromatic contrast of approximately 70%. In addition, this system achieved high electrochromic efficiency (over 70 cm2 C?1 at 630 nm) and a response time that could be measured in milliseconds. The electrode was cycled more than 103 times, indicating excellent stability.