IN-SITU RESONANCE RAMAN MEASUREMENTS OF A HYBRID ELECTROCHROMIC CELL WITH A GEL REDOX (I3-/I-) ELECTROLYTE

IN-SITU RESONANCE RAMAN MEASUREMENTS OF A HYBRID ELECTROCHROMIC CELL WITH A GEL REDOX (I₃^-/I^-) ELECTROLYTE

Angela Šurca Vuk, Boris Orel,*

National Institute of Chemistry, Hajdrihova 19, SI–1000 Ljubljana, Slovenia

Philippe Colomban

LADIR UMR 7075 CNRS & Paris VI University, 2 Rue Henry Dunant, 94320 Thiais, France

Abstract

A hybrid electrochromic (HEC) device was constructed from optically active nanocrystalline WO₃ film and transparent platinised SnO₂:F-glass electrodes encapsulating a gel redox electrolyte. The electrolyte was prepared from an organic-inorganic ICS-PPG precursor that was synthesized from bis end-capped triethoxy silane and poly(propyleneglycol)-bis-(2-amino-propyl)ether (MW = 4000). KI and I₂ in a molar ratio KI:I₂ = 10:1 were a source of an I₃^-/I^- redox pair while valeric acid was used as a catalyst for the solvolysis reactions of the ICS-PPG precursor. The stability and kinetics of colouring/bleaching changes of the HEC device were determined by using in-situ UV-visible spectroelectrochemical measurements between +2 and –2 V (CV, CC).