Tungsten trioxide films

Solarska R, Santato C, Jorand-Sartoretti C, M. Ulmann and J. Augustynski (2005) Photoelectrolytic oxidation of organic species at mesoporous tungsten trioxide film electrodes under visible light illumination. J Appl Electrochem 35 715-721... 

Santato, C., Ulmann, M., Augustynski, J. Photoelectrochemical properties of nanostructured tungsten trioxide films. J. Phys. Chem. B 105, 936 (2001)... 

Smith, D., Falconer, R., Wittman, E. L. Vetelino, J. F. (1993). StabiUty, sensitivity and selectivity of tungsten trioxide films for sensing apphcations. Sensors and Actuators B, Vol. 13-14, pp. 264-268... 

Among the most reviewed oxide layers used for electrochromic layers are tungsten trioxide films [22-26], WO3 forming bilayers [27] or coatings based on... 

Members of the ion-insertion/extraction group, as inorganic or organic thin films, especially the former, have attracted the widest interest most recently. Tungsten trioxide was the eadiest exploited inorganic compound (4), even before the mechanism of its electrochromic response was understood (5). It is stiU the best known of the important ion-insertion/extraction group. 

Figure 23 Photograph of a working tandem device based on a thin film of polycrystalline tungsten trioxide...

Figure 8.1 Beer s law-type plot of change in optical absorbance against charge density q for the cell WO3 polymer electrolyte Prussian Blue. Reprinted from Inaba, H Iwaka, M., Nakase, K., Yasukawa, H., Seo, I. and Oyama, N., Electrochromic display device of tungsten trioxide and Prussian Blue films using polymer gel electrolyte of methacrylate , Electrochim. Acta, 40, 227-232 (1995), Copyright 1995, with permission from Elsevier Science.

Figure 8.14 Huggins analysis of a Warburg element in a Nyquist plot such as that shown in Figure 8.12(a), for the diffusion of Li" ions through solid-state WO3. The traces for Z and Z" against will not be parallel for features other than that of the Warburg. From Ho, C., Raistrick, I. D. and Huggins, R. A., Application of AC techniques to the study of lithium diffusion in tungsten trioxide thin films , J. Electrochem. Soc., 127, 343-350 (1980). Reproduced by permission of The Electrochemical Society, Inc.

The author was brought up in Hastings, on England s south coast, where he attended a local comprehensive school. Despite this education, he achieved entrance to the University of Exeter to read Chemistry. Having obtained a B.Sc. degree and then a doctorate (in 1989) on the electrochemistry of the viologens, he was awarded a fellowship at the University of Aberdeen to study the electrochromism of thin films of tungsten trioxide. 

Pure tungsten trioxide, WO3, is very pale yellow and practically colourless in thin films, whilst the reflected colour of the reduction product, is... 

Tungsten trioxide thin films activated by gold layers have also been used for NOj. detection.115 This material possesses excellent sensitivity towards nitric oxide and nitrogen dioxide. An automobile exhaust gas NO sensor that uses a gold-platinum alloy electrode has also been reported.116... 

Metal oxide films which change color in an electrolyte with change in applied potential [11, 115-123,127, 128, 137] have attracted a lot of attention in the past 15 years or so because of their potential application in electrochromic displays. Tungsten trioxide was the first oxide to receive significant attention in this regard [115-119] and, later, Ir oxide films [11, 120, 121, 127,... 

A tandem device that achieves the direct cleavage of water into hydrogen and oxygen by visible light was developed in collaboration with two partner groups from the Universities of Geneva and Bern [123]. This is based on the in-series connection of two photosystems. A thin transparent film of nanocrystalline tungsten trioxide or ferric oxide absorbs the blue part of the solar spectrum (Eq. (63)). 

N. Leventis Y. C. Chung, Preparation And Characterization Of Tungsten Trioxide Dibenzyl Viologen Polymer Bilayer Electrochromic Films. J. Mater. Chem. 1993, 3, 833-839. 

Preliminary work on electrosynthesis of mesoporous tungsten trioxide (WO3) and titanium dioxide (Ti02) films from a peroxo-stabilized electrol using ionic surfactants has at last shown definitive evidence of highly structured materials (July 2002)... 

Cathodic Electrochromic Materials—Tungsten Trioxide. Figure 4.3.20 shows electrochemical impedance spectra on both amorphous and crystalline Li containing WO3 films together with fits to the Randles circuit (Strpmme Mattsson [2000]). For the amorphous film the high frequency semicircle overlaps with the diffusion response. In the case of the crystalline film, only a part of the semicircle due to Cdi and Ra, can be observed. As is obvious from the displayed spectra, the charge transfer resistance is much larger for the crystalhne sample than for the disordered one at an equilibrium potential of 2.9 V vs. the Li reference electrode used in the experiment. Impedance spectra were taken at several equihbrium potentials, and in all cases the impedance response corresponded to that of the Randles circuit with a Zd of semi-infinite type. 

P. M. S. Monk [1999] Charge Movement through Electrochromic Thin Film Tungsten Trioxide. Crit. Rev. Solid State Mater. Sci. 24, 193—226. 

Diffusion in Tungsten Trioxide Thin Films, J. Electrochem. Soc. 129, 2349-2354. 

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