Electrochromic materials hybrid

Stabilization of the redox cycle is relatively important in construction of potentially useful electrochromic materials, because the molecules needed for application require high redox-stability. Recently, S. Hiinig et al. proposed the concept of violene-cyanine hybrid to produce stabilized organic electrochromic materials (3). The hybrid is constructed by a violene-type redox system containing delocalized closed-shell polymethine dyes as end groups. The hybrid is expected to exhibit the color of a cyanine dye, by an overall two-electron... 

In addition to the previous architectures, two more alternatives are possible for the structure of an electrochromic device (1) the solution configuration, including an electrochemical cell having an electrochromic material (or two) dissolved in a liquid or gel electrolyte (Figure 20.7b), and (2) the hybrid... 

Nanocarbon hybrids have recently been introduced as a new class of multifunctional composite materials [18]. In these hybrids, the nanocarbon is coated by a polymer or by the inorganic material in the form of a thin amorphous, polycrystalline or single-crystalline film. The close proximity and similar size domain/volume fraction of the two phases within a nanocarbon hybrid introduce the interface as a powerful new parameter. Interfacial processes such as charge and energy transfer create synergistic effects that improve the properties of the individual components and even create new properties [19]. We recently developed a simple dry wrapping method to fabricate a special class of nanocarbon hybrid, W03 /carbon nanotube (CNT) coaxial cable structure (Fig. 17.2), in which W03 layers act as an electrochromic component while aligned... 

Not surprisingly, the research field of electrochromic compounds is very broad and includes inorganic, organic, and polymeric as well as several hybrid materials. We shall therefore attempt to give a brief overview of past and current achievements before we present our own contributions. Due to its scope, this chapter cannot be considered comprehensive, and the reader is referred to recent review articles for a more detailed description. [26,27,33]. 

The combination of favorable properties of PANI and TiO opens the possibility for various applications of PANI/TiO nanocomposite materials, such as piezoresistivity devices [41], electrochromic devices [99,118], photoelectrochemical devices [43,76], photovoltaic devices/solar cells [44,50,60,61,93,119], optoelectronic devices/UV detectors [115], catalysts [80], photocatalysts [52,63,74,75,78,84,87,97,104,107,121,122,125], photoelectrocatalysts [122,123], sensors [56,61,65,69,85,86,95,120,124], photoelectrochemical [110] and microbial fuel cells [71], supercapacitors [90,92,100,109,111], anode materials for lithium-ion batteries [101,102], materials for corrosion protection [82,113], microwave absorption materials [77,87,89], and electrorheological fluids [105,106]. In comparison with PANI, the covalently bonded PANI/TiO hybrids showed significant enhancement in optical contrast and coloration efficiency [99]. It was observed that the TiO nanodomains covalently bonded to PANI can act as electron acceptors, reducing the oxidation potential and band gap of PANI, thus improving the long-term electrochromic stability [99]. Colloidal... 

In a dual polymer ECD, the redox-active material at both electrodes is an electrochromic polymer, while in a hybrid device the material at the working electrode is an electrochromic polymer and the material at the counter electrode is an inorganic (e.g., WO3 or PB) or molecular organic (e.g., polyviologen) electrochrome [4,5,16,239,249,250]. 

Thakur VK, Ding G, Ma J, Lee PS, Lu X. Hybrid materials and polymer electrolytes for electrochromic device applications. Adv Mater 2012 24 4071-4096. 

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