D. Louloudakis; D. Vernardou; G. Papadimitropoulos; D. Davazoglou; E. Koudoumas
Abstract
Results are presented regarding the development of functional electrochromic WO3 thin layers, using a simple, one step and fast process without the need of template or seed layers or even post-annealing, factors favoring large scale industrial deposition. In particular, low-pressure chemical vapor deposition ...
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Results are presented regarding the development of functional electrochromic WO3 thin layers, using a simple, one step and fast process without the need of template or seed layers or even post-annealing, factors favoring large scale industrial deposition. In particular, low-pressure chemical vapor deposition (LPCVD) was employed to develop gama-monoclinic WO3 crystalline phase of granular agglomerations structure, with a thickness from 60 nm up to 160 nm onto FTO coated glass substrates. The effect of growth time and oxygen flow on the structural, morphological and electrochemical properties of WO3 thin layers was investigated. It was found that a deposition time of 15min and an O2 flow rate through the reactor of 0.1 l/min result in a more stable behavior during the interchange charge circles.
Dimitra Vernardou; Emmanouil Spanakis; Nikolaos Katsarakis; Emmanouil Koudoumas
Abstract
Vanadium oxides were electrodeposited on fluorine doped tin dioxide glass substrates using an aqueous solution of ammonium metavanadate at room temperature for various growth periods keeping the current density constant. The deposition period was found to affect the structure and the morphology of the ...
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Vanadium oxides were electrodeposited on fluorine doped tin dioxide glass substrates using an aqueous solution of ammonium metavanadate at room temperature for various growth periods keeping the current density constant. The deposition period was found to affect the structure and the morphology of the oxides indicating low crystalline quality and smooth surfaces respectively for periods < 2000 s. It has been found that crystalline vanadium pentoxide grown for 2000 s presented the highest amount of charge, being 0.43 0 C interchanged between the oxide and the electrolyte with a respective specific capacitance of 286 F g -1 having a satisfactory stability after 500 continuous scans. The significance of achieving crystalline low-cost vanadium pentoxide at room temperature with enhanced electrochemical properties for applications as electroactive material is highlighted.