Abstract—Electrochromic iridium oxide thin films were deposited by spray pyrolysis technique onto indium-doped tin oxide (ITO) coated glass substrates using iridium chloride as an aqueous solution. The influence of the substrate temperature, the deposition period of time and the solution molarity have been investigated as related to the film’s electrochromic (EC) performance. The electrochromic properties of the films were investigated in a (0.5M H₂SO₄) aqueous electrolytic solution using cyclic voltammetry (CV). The transmittance has been measured over the spectral wavelength range between 300 and 2400 nm. The substrate temperature (T_sub), the deposition period of time, the solution molarity and the colouration and bleaching potentials were optimized and found to be 400 oC, 10 min, 0.02 M, ±0.8 V, respectively. The films have acquired a maximum transmittance solar modulation ΔTs and a maximum visible modulation ΔTv at 630 nm optimal optical modulation. The iridium oxide thin films have demonstrated a pronounced anodic electrochromic behavior owing to Ir⁺⁴ =Ir⁺³ intervalance charge transitions.

Index Terms—Electrochromic iridium oxide, cyclic voltammetry, solar and visible modulation, coloration and bleaching.

S. A. Mahmoud and A. S. Riad are with the Physics Department, Faculty of Science, Hail University, Hail, Kingdome of Saudi Arabia (e-mail: samahmoud2002@yahoo.com, asr_rizk@hotmail.com).
M. M. El-Deeb is with Chemistry Department, Faculty of Science, Hail University, Hail, Kingdome of Saudi Arabia and Chemistry Department, Faculty of Science, Beni-Suef University, 62514 Beni-Suef, Egypt.
Tarek Ben Nasrallah is with the Physics Department, Faculty of Science, Hail University, Hail, Kingdome of Saudi Arabia and Université de Tunis El Manar, Faculté des Sciences de Tunis, Unité de physique des dispositifs à semi-conducteurs, Tunis, Tunisie (e-mail: nasrallah.tarek@gmail.com).

Cite: S. A. Mahmoud, A. S. Riad, M. M. El-Deeb, and Tarek Ben Nasrallah, "Influence of Some Preparative Parameters on Microstructure and Electrochromic Behavior of Sprayed Iridium Oxide Films," International Journal of Applied Physics and Mathematics vol. 3, no. 6, pp. 381-386, 2013.