Black electrochromic ink with a straightforward method using copper oxide nanoparticle suspension.

Content Provider	Europe PMC
Author	Jeong, Chan Yang Watanabe, Hiroshi Tajima, Kazuki
Abstract	Electrochromic (EC) materials for smart windows must exhibit a dark colour and block visible light (wavelength = 380-780 nm) to reduce environmental impact. In particular, black tones are also desired, and there are many reports of attempts to create these dark tones using organic materials such as polymers. However, their fabrication methods are complicated, expensive, and may even use hazardous substances; moreover, they are often not sufficiently durable, such as upon exposure to ultraviolet light. There are some reported cases of black materials using the CuO system as an inorganic material, but the synthesis method was complicated and the functionality was not stable. We have found a method to synthesize CuO nanoparticles by simply heating basic copper carbonate and adjusting the pH with citric acid to easily obtain a suspension. The formation and functionality of CuO thin films were also demonstrated using the developed suspension. This research will enable the creation of EC smart windows using existing inorganic materials and methods, such as printing technology, and is the first step towards developing environment-friendly, cost-effective, and functional dark inorganic materials.
Journal	Scientific Reports [Sci Rep]
Volume Number	13
DOI	10.1038/s41598-023-34839-9
PubMed Central reference number	PMC10182978
Issue Number	1
PubMed reference number	37179398
e-ISSN	20452322
Language	English
Publisher	Nature Publishing Group
Publisher Date	2023-05-13
Publisher Place	London
Access Restriction	Open
Subject Keyword	Nanoparticles Synthesis and processing
Content Type	Text
Resource Type	Article
Subject	Multidisciplinary