electrochromism, bismuth tungstate, nickel tungstate, injection, extraction.

How to Cite

Smilyk , V., Fomaniyk, S., Kolbasov , G., Rysetskiy , I., & Danilov , M. (2021). PHOTOELECTROCHEMICAL PROPERTIES OF FILMS BASED ON BISMUTH AND COPPER VANADATES. Ukrainian Chemistry Journal, 87(1), 3-12.


Films of bismuth and nickel tungstates were obtained by chemical and electrochemical synthesis. Bismuth tungstate was obtained by ionic layering and electrochemical deposition. Nickel tungstate (NiWO4) was obtained by combined synthesis methods: 1st - electrochemical synthesis and 2nd - combined electrochemical and thermochemical synthesis. The obtained materials have good adhesion with an optically transparent SnO2 substrate. It is shown that the mechanism of electrochemical formation of Bi2WO6 and NiWO4 films is similar to the processes of WO3 formation as a result of electroreduction of peroxide-complex compounds based on tungstate ions, which were studied in detail in. From the data of coloring kinetics the speed, efficiency and stability of electrochromic material depending on its cycling time are estimated. It is shown that tungstates can cycle for a long time with galvanostatic current change and different potentials. Comparison of electrochromic properties of nickel and bismuth tungstate films obtained by ionic stratification, electrodeposition and combined electrochemical and thermochemical methods showed that polycrystalline films have a lower color contrast compared to films obtained by electrodeposition. Using X-ray phase analysis, it was found that the structure of the obtained materials depended on the method of production. Comparison of X-ray diffraction data for chemically and electrochemically obtained Bi2WO6 showed that the films obtained by electrochemical deposition have more amorphous structure, possibly with inclusions of orthorhombic Bi2WO6 and hexagonal WO3 crystallites, while the films obtained by ionic layering have a layer of polycrystals, indicates the fine-grained obtained crystallites. The studied properties of Bi2WO6 and NiWO4 meet the requirements for electrochromic materials in terms of providing high color contrast in the visible part of the spectrum.


1. Granqvist C.G., Green S., Niklasson G.A., Mlyuka N.R., Kr.mer S., Georen P. Advances in chromogenic materials and devices. Thin Solid Films. 2010. 518: 3046.
2. Yakovleva D. S. Electrochromic effect in hydrated vanadium pentoxide. Avtoreferat disertacії. 2015.
3. Pereira L. Electrochromic materials for smart devices. EPOSS Anual Forum Lisbon. 2010. URL:
4. Granqvist C.G. Handbook of Inorga­nic Electrochromic Materials. Amsterdam. 2002. 272: 650.
5. Dinh N.N., Ninh D.H., Thao T.T., Vo-Van T. Mixed Nanostructured Ti-W Oxi­des Films for Efficient Electrochromic Windows. Journal of Nanomaterials. 2012. 2012:7.
6. Wyckoff, R. W. G. The Structure of Crystals. Interscience Publishers, Inc. 1951. 3: 41.
7. Kazemzadeha A., Eskandaria A., Goudarzia F. Structural and Optical characterization Of Nickel Tungstate Nano Crystallites Synthesized Via Polyol Method. The 4th International Conference on Nanostructures (ICNS4). 2012. 26: 10.
8. Meulenkamp E. A.. Mechanism of WO3 electrodeposition from peroxy-tungstate solution. Journal of the Electrochemical Society. 1997. 144: 1664.
9. Vas’ko A. T., Pacyuk F. N., Shkarav­skij YU. F. Influence of electrolysis conditions on the tungsten content in the galvanic deposit. Elektrohimiya vodnyh rast­vorov. 1981. 117: 73.
10. Vas’ko A. T., Krasnov YU. S., Pacyuk F. N., Chumak S. M. Control of the deposition of optically inhomogeneous films by the method of two-beam laser interferometry. Ukrainskij himicheskij zhurnal. 1985. 51 (2): 152.
11. Patsyuk F.N. Electroreduction of wolfram (VI) and investigation of the electrochemical properties of cathode deposits: avtoref. dis. kand. him. nauk. 1984. 1: 20.
12. Sych O. A., Krasnov YU. S., Vas’ko A. T., Pacyuk F. N., Lastochkina I. E . Ultimate excitation overvoltage on electrochromic films of amorphous tungsten trioxide. Ukrainskij himicheskij zhurnal. 1991. 57 (6): 628.
13. Liang L., Zhang J., Zhou Y., Xie J. High-performance flexible electrochromic device based on facile semiconductor-to-metal transition realized by WO3•2H2O ultrathin nanosheets. Scientific Reports. 2013. 3: 11.
14. Krasnov Yu. S., Kolbasov G. Ya. Electrochromism and reversible changes in the position of fundamental absorption edge in cathodically deposited amorphous WO3. Electrochimica Acta. 2004. 49 (15): 2425.
15. Campos W. Ed., Nobre F. X. High Photocatalytic Activity under Visible Light for a New Morphology of Bi2WO6 Microcrystals. Catalysts. 2019. 9: 667.
16. Mulik R.N., et al. Hydrothermal synthesis of tungsten oxide (WO3) for the detection of NO2 gas. 17th International Meeting on Chemical Sensors. 2018. 17: 531.


Download data is not yet available.