Coloration efficiency

An important way to assess the many iasertion/extraction films known is to compare spectral coloration efficiencies, CE(X), for the visible region. 

It is important, however, to realize that whilst many types of chemical species exhibit electro-chromism, only those with favorable electrochromic performance parameters1 are potentially useful in commercial applications. Thus, most applications require electrochromic materials with a high contrast ratio, coloration efficiency, cycle life, and write-erase efficiency.1 Some performance parameters are application dependent displays need low response times, whereas smart windows can tolerate response times of up to several minutes. 

Bhandari, S. Deepa, M. Srivastava, A. K. Lai, C. Kant, R., Poly(3,4-Ethylenedioxythiophene) (Pedot)-Coated Mwcnts tethered to conducting substrates Facile electrochemistry and enhanced coloring efficiency. Macromol Rapid Commun 2009, 30,138-138. 

In addition to their immense variability, conducting polymers are characterized by several other key advantages, such as fast (subsecond) switching times, high coloration efficiency, durability, mechanical flexibility, and facile process-ability. 

Gaupp, C.L., Welsh, D.M., Ranh, R.D., and Reynolds, J.R. 2002. Composite coloration efficiency measurements of electrochromic polymers based on 3,4-alkylenedioxythio-phenes. Chemistry of Materials 14, 3964—3970. 

Where C.I, the color intensity is the sum of absorbance at 420, 520,620 nm, and o.d 280 is the absorbance measured at 280nm (in a 1cm quartz cell) after a one hundred fold dilution. This index is in fact measuring the coloring efficiency of the phenolic compounds present in red wines. 

The coloration efficiency of photochromic spirocompounds may be enhanced by careful selection of additional chromophoric substituents. Tomasulo et al. reported amplification of coloration efficiency of photochromic oxazines using a bichromo-phoric approach [25],... 

The UV-mediated photolysis of the C-0 bond produced simultaneously two chromophores (see Fig. 6.4) phenolate anion (chromophore 1) and indolium cation (chromophore 2), which absorb in the same region of the visible spectrum resulting in an amplification (doubling) of the coloration efficiency. 

Composition Color Efficiency -X-ray Excit. Peak.nm X-ray Response... 

The successful application of Ir(ppy)3 as a phosphorescent dopant has led to a number of synthetic modifications of the parent complex. Most of the new derivatives were prepared in order to alter the luminescent properties (color, efficiency, stability, etc.) or to further characterize the excited-state properties of these materials. Tris-cyclometal-lated Ir complexes can be prepared using two general methods, either by direct formation in a one-step reaction or with a two-step synthesis that uses a /t-dichloro-bridged dimeric complex as an isolated intermediate. The first efficient direct synthesis to be reported involved the reaction of Ir(acac)3 (acac = acetylacetonate) with an excess of... 

The quantum yield of photolysis of carbon tetrabromlde could be determined by gas chromatographic measurements and the coloration efficiency could be determined by spectrophotometrical monitoring of the formation of the pyrylium salt at 630 nm. By comparison of both values It appears that approximately 50% of the decomposed carbon tetrabromlde produces hydrogen bromide, which is responsible for the formation of dye molecules. A typical Imaging system based on these materials gives a sensitivity of... 

Green color efficiency and lifetime improvement at Kodak as a function of year. Data at 20mA/cm. ... 

Blue color efficiency and lifetime improvement at Kodak as a function of year. Numbers in parentheses are ClEx,y values. Black points have CIEy values below 0.17, grey points have CIEy points above 0.17. Data at 20mA/cm. ... 

Higher coloration efficiency, larger charge capacity, enhanced cycling stability and faster color-bleach rates were observed for nanofibrUlar PANI films, obtained by electropolymerization from an aqueous medium in the presence of an ionic liquid (1-ethyl, 3-methylimidazolium bromide), as compared to that shown by nonfibrillar PANI films fabricated from PEG solution [279]. 

S. Bhandari, M. Deepa, A.K. Srivastava, C. Lai, and R. Kant, Poly(3,4-ethylenedioxythio-phene) (pedot)-coated MWCNTs tethered to conducting substrates Facile electrochemistry and enhanced coloring efficiency, Macromol. Rapid Commun., 29(24), 1959-1964 (2008). 

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