Solid-state properties of thin film electrochromic cobalt–nickel oxide

✍ Scribed by Paul M.S. Monk; Shehnilah Ayub

• Publisher: Elsevier Science
• Year: 1997
• Tongue: English
• Weight: 473 KB
• Volume: 99
• Category: Article
• ISSN: 0167-2738
• DOI: 10.1016/s0167-2738(97)00148-3

✦ Synopsis

Thin film mixtures of cobalt(II) 1 nickel(II) oxyhydroxide have been prepared by electrodeposition from water on to platinum. The chemical diffusion coefficient D of the hydroxide ion through the mixed oxide has a marked temperature dependence; and Eyring-type graphs have two linear regions. The temperature at which there is a change from one linear ŕegion to the other corresponds to the Neel transition temperature T for cobalt-nickel oxide. It is seen that the chemical N diffusion coefficient D decreases with increasing temperature at some compositions rich in NiO, and this is discussed in 21 2

terms of an increased mobility of oxide (or maybe Ni ) species competing with the movement of OH in an anionic type of 'mixed alkali' effect. It is suggested that systems evincing both a Neel transition (at T ) and a Verwey transition (at T ) N V ought to show T ¯T .