Electrochromism switching time

Nanomaterials of undoped vanadia employed in electrochromic studies include nanowires [35-37], inverse opals [34], and mesoporous films [38]. Similar attempts were undertaken for NiO devices [39 2]. Although these recent attempts brought about an improvement in electrochromic performance, the reported switching times remained 1-2 orders of magnitude above the desired video rate of 24 frames per second [34-38]. This is mainly due to the use of sub-optimal MO morphologies in terms of their structural dimension, connectivity and integrity. 

Chen, X., Xu, Z., Mi, S., Zheng, J., Xu, C., 2015b. Spray-processable red-to-transmissive electrochromic polymers towards fast switching time for display applications. New I. Chem. 39,5389-5394. 

PEDOT is dark opaque blue in its reduced form and transmissive light blue in its oxidized form [ 107]. On this basis, efforts directed to the application of EDOT-based polymers in electrochromic devices have been focused on the improvement of the solubility, stability, switching time, and optical contrast [58,291,292]. 

Electrospun conducting polymer nanofibers (diameter ca. 120 nm) also exhibited a desirable electrochromic property [438]. The electrospun conducting polymer nanofibers formed an interconnected network by solid/ swollen-state oxidative crosslinking without significant perturbation of the morphology. Nanofibers showed relatively fast switching times of 2-3 s. 

The best performing is pMeT. Switching it between 2.5 and 4 V vs Li shows an electrochromic efficiency at 530 nm of 240mC cm, a very high value. Its electrochromic response time is also satisfactory, the transmittance... 

The production of patterned, rapid-switching, reflective ECDs has been demonstrated by Aubert et al. with active electrochromic materials such as PEDOT, (PProDOT) and the dimethyl-substituted derivative PProDOT-Me2, whose resulting switching times were 0.1-0.2 s (5-10 Hz) [51, 56]. In another dual-type polymer PEDOT and PBEDOT-B(OCi2H2s)2 reflective device, a 2 x 2 pixelated lateral configuration has been shown. 

Dual-type polymer electrochromic devices based on copolymers of 2-benzyl-5,12-dihydro-27f-pyrrolo [3, 4 2,3] [1, 4]dioxocino[6,7-6]quinoxaline (DPOQ) and 5,12-dihydrothieno[3, 4 2,3] [1, 4]dithiocino [6,7- >]quinoxaline (DTTQ) with bithiophene were developed. P (DPOQ-co-BT) and P(DTTQ-co-BT) were used as the anodically coloring and PEDOT as the cathodically coloring electrochromic materials [81]. Each device performed with a favorable switching time, optical contrast, open-circuit memory and stability. 

Dual-type absorptive/transmissive polymer electrochromic devices based on poly[thiophen-3-ylacetic acid 4-pyrrol-1-ylphenyl ester (TAPE)-co-A -methylpyrrole (NMPy)] and PEDOT have been assembled, which exhibit good optical memory, stability with moderate switching times and light yellow and green colors upon doping and dedoping, respectively [82],... 

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