The ability to match two complementary polymers constitutes an important step forward in the design of electrochromic devices (ECDs). Here we show that the necessary control over the color, brightness, and environmental stability of an electrochromic window can be achieved through the careful design of anodically coloring polymers. For this purpose, we have constructed ECDs based on dimethyl substituted poly(3,4-propylenedioxythiophene) (PProDOT-Me 2 ) as a cathodically coloring layer, along with poly[3,6-bis(2-ethylenedioxythienyl)-N-methyl-carbazole] (PBEDOT-NMeCz) and N-propane sulfonated poly(3,4-propylenedioxypyrrole) (PProDOP-NPrS) as anodically coloring polymers. Comparison of the results shows that using PProDOP-NPrS as the high band gap polymer has several advantages over the carbazole counterpart. The main benefit is the opening of the transmissivity window throughout the entire visible spectrum by moving the π-π* transition of the neutral anodically coloring material into the ultraviolet region. Another advantage of the PProDOPNPrS based device is the noticeable increase in the optical contrast as evidenced by an increase in the transmittance change of the device (∆%T) from 56% to 68%, as measured at 580 nm. These devices exhibit a 60% change in luminance along with half-second switching times for full color change. Moreover, they were found to retain up to 86% of their optical response after 20 000 double potential steps, opening up new directions in optical technology.

A series of poly (3,4-alkylenedioxypyrrole)s are reported as a new class of electronically conducting polymers exhibiting especially low oxidation potentials from ca. -0.6 to -0.4 V vs Fc/Fc + (equivalent to -0.15 to +0.05 V vs SCE) as desired for ambient stability of the doped and conducting states. These polymers exhibit unique combinations of multicolor electrochromism, switching from a red or orange neutral state to a light blue/gray doped state, passing through a darker intermediate state (brown), as examined by in situ colorimetry. High spectral contrast ratios have been measured throughout the visible region with a maximum ∆%T ) 76% at 534 nm for poly[3,4-(2,2-dimethylpropylenedioxy)pyrrole) (PProDOP-(CH3)2). PProDOP-(CH3)2 exhibits outstanding redox switching stability, being able to undergo 40 000 deep double-potential switches between its doped and neutral states (1 s, ∆%Tmax ) 76%) while retaining more than 90% of its electroactivity. A high level of stability to overoxidation has also been observed as these materials show limited degradation of their electroactivity at potentials 2 V above their half-wave potential. Triflate-doped free-standing films of PEDOP and PProDOP, having high electrical conductivities of 83 and 95 S/cm, respectively, have been obtained by galvanostatic deposition at low temperature (-7 °C).