(Invited) Durability of Electrochromic Films: Aging Kinetics and Rejuvenation. (7th July 2017)

• Record Type: Journal Article
• Authors: Niklasson, Gunnar A.; Wen, Rui-Tao; Qu, Hui-Ying; Arvizu, Miguel A; Granqvist, Claes-Goran
• Is Part Of: ECS transactions. Volume 77:Number 11(2017)
• Page Start: 1659
• Page End: 1669
• Publication Date: 2017-07-07
• Subjects: Electrochemistry -- Periodicals; Electrochemistry; Periodicals; Electronic journals; Electronic journal; 541.37
• DOI: 10.1149/07711.1659ecst
• Languages: English
• ISSNs: 1938-5862

Abstract

Abstract : A major challenge for energy-efficient smart window technology is to ensure the durability of electrochromic (EC) devices over a service life of more than 20 years. In this paper, we report recent results from a fundamental study of the aging kinetics of EC tungsten oxide and nickel oxide thin films and describe electrochemical rejuvenation mechanisms that are able to restore the films to their initial state. The aging kinetics displays an approximate power-law decrease of the charge capacity as a function of cycle number. This decay of charge capacity can be understood in terms of models built on so-called dispersive chemical kinetics. Tungsten oxide and nickel oxide EC films can be rejuvenated by applying a high electrochemical potential or a small constant current. Trapped ions in the bulk or at the surface of the films can be released by these procedures.