High contrast solid state electrochromic devices based on Ruthenium Purple nanocomposites fabricated by layer-by-layer assembly

Abstract

Electrochromic Ruthenium Purple-polymer nanocomposite films, fabricated by multilayer assembly, were found to exhibit sub-second switching speed and the highest electrochromic contrast reported to date for any inorganic material.

A WO3–poly(butyl viologen) layer-by-layer film/ruthenium purple film based electrochromic device switching by 1 volt application

“…8b). The value at λ max is comparable with reported highest coloration efficiency of 205 cm 2 C À 1 for a solid-state electrochromic device based on RP nanocomposite [33]. The digital photographs of (i) the as-deposited RP film, (ii) fully bleached (E ¼ À0.8 V), and (iii) fully colored (E ¼ þ1.0 V) states of RP are shown in Fig.…”

“…In the past, RP thin films were electrodeposited from a solution containing a soluble RP colloid, prepared by dissolving FeCl 3 and potassium hexacyanoruthenium(II) in water [30]. Linear polyethylene imine (LPEI)-RP multilayered nanocomposites were also fabricated in the past using LbL technique and a transmittance change of 84% at 560 nm and a coloration efficiency of 205 cm 2 C À 1 were reported [33].…”

Synthesis, characterisation and in situ colorimetry of electrochromic Ruthenium purple thin films

“…The peaks at 17.0° (200), 24.5° (220), 34.1°(400), and 44.8° (420) are in close agreement with those found for bulk synthesis of RP powder in the present work and from the literature [19]. The RP can be indexed as a face-centred cubic structure and belongs to the space group Fm3m [19].…”

“…Although thin-film PB is readily available through electrochemical reduction of solutions containing iron(III) and hexacyanoferrate(III) ions [6][7][8][9], synthesis of RP films [10][11][12][13][14][15][16][17][18][19] is less straightforward. Salts of the analogous hexacyanoruthenate(III) ion are not commercially available, and although preparation by chemical or electrochemical oxidation of hexacyanoruthenate(II) is possible, the resulting solution is unstable.…”

Fast switching electrochromism from colloidal indium tin oxide in tungstate-based thin film assemblies

“…A variety of functional thin films have been produced using the LbL technique, including antimicrobials [31,32], gas barriers [33,34], sensors [35,36], membranes for fuel cells [37][38][39], drug delivery [40][41][42], field-effect transistors [43,44], and electrically conductive coatings [45,46]. Additionally, many electrochromic thin films have been prepared using the LbL method with poly(3,4-ethylenedioxythiophene) [47], Ruthenium Purple [48], Prussian Blue [49], poly(aniline-N-butylsulfonate)s [50], and viologen [51]. The tungstate anion goes through an analogous color change to WO 3 and can be deposited using LbL methodology.…”