Multistep colorization of Co(OH)2/Ni(OH)2 electrochromic film prepared by a simple chemical bath deposition method
M Alvien Ghifari (a*), Desti Riandiani (a), Juwita Sari (a), I Putu Mahendra (a), Demi Dama Yanti (a), Indah Puspita Sari (b) Yayuk Astuti (c) Adi Darmawan (c)

a) Department of Chemistry, Faculty of Science, Institut Teknologi Sumatera, Jalan Terusan Ryacudu, Lampung Selatan, 35365, Indonesia
*m.ghifari[at]ki.itera.ac.id
b) Department of Cosmetic Engineering, Faculty of Production and Industry Technology, Institut Teknologi Sumatera, Jalan Terusan Ryacudu, Lampung Selatan, 35365, Indonesia
c) Department of Chemistry, Faculty of Science and Mathematic, Diponegoro University, Jalan Prof. Prof Sudharto, SH, Semarang 50275, Indonesia

Abstract

Electrochromic-based smart windows offer the controlling ability of sunlight irradiation under applied voltage. In this study, electrochromic film of Co(OH)2/Ni(OH)2 composites on ITO glass was successfully synthesized by simple chemical bath deposition. Two different processes were conducted to investigate the optical character of the deposited film. The characteristics of the composites were analyzed by UV-Vis, XRD, and SEM. All Co(OH)2/Ni(OH)2 films exhibit stepping colorizations under various applied voltages. The transmittance change (\triangle\T) and optical density (\triangle\OD) of the mixed Co(OH)2/Ni(OH)2 at 500 nm under 0.15 and 0.75 V are 11.10 % and 0.09, and 50.14 %, and 0.91 . Meanwhile, \triangle\T and &\triangle\OD of the double-layer Co(OH)2/Ni(OH)2 are 1.36 % and 0.13, and 9.64 % and 9.31 under same conditions. The results show that Co(OH)2 addition is beneficial to get step colorization in Ni(OH)2 electrochromic film. The mixed Co(OH)2/Ni(OH)2 has better optical modulation than double-layer Co(OH)2/Ni(OH)2.

Keywords: Electrochromic, composite, Co(OH)2, Ni(OH)2, chemical bath

Topic: Inorganic Chemistry