1 research outputs found
Terpyridine-Based Monolayer Electrochromic Materials
Novel
electrochromic (EC) materials were developed and formed by a two-step
chemical deposition process. First, a self-assembled monolayer (SAM)
of 2,2′:6′,2″-terpyridin-4′-ylphosphonic
acid, L, was deposited on the surface of a nanostructured conductive
indium–tin oxide (ITO) screen-printed support by simple
submerging of the support into an aqueous solution of L. Further reaction
of the SAM with Fe or Ru ions results in the formation of a monolayer
of the redox-active metal complex covalently bound to the ITO support
(Fe–L/ITO and Ru–L/ITO, respectively). These novel light-reflective
EC materials demonstrate a high color difference, significant durability,
and fast switching speed. The Fe-based material shows an excellent
change of optical density and coloration efficiency. The results of
thermogravimetric analysis suggest high thermal stability of the materials.
Indeed, the EC characteristics do not change significantly after heating
of Fe–L/ITO at 100 °C for 1 week, confirming the excellent
stability and high EC reversibility. The proposed fabrication approach
that utilizes interparticle porosity of the support and requires as
low as a monolayer of EC active molecule benefits from the significant
molecular economy when compared with traditional polymer-based EC
devices and is significantly less time-consuming than layer-by-layer
growth of coordination-based molecular assemblies