Chua, M. H., Soo, X. Y. D., Goh, W. P., Png, Z. M., Zhu, Q., & Xu, J. (2022). Thioxanthylium Cations: Highly Reversible Hydrochromic Mate‐rials with Tunable Color and Moisture Sensitivity. Chemistry – A European Journal, 28(65). Portico. https://doi.org/10.1002/chem.202201975
Abstract:
AbstractHydrochromic materials, which change color in response to moisture, are highly sought‐after due to some unique applications such as moisture detection, humidity monitoring, anti‐counterfeiting, and sweat‐pore mapping. We herein report a new thioxanthene‐9‐ols/thioxanthylium cations hydrochromic system. The hydrochromic thioxanthylium cations can be generated/regenerated by exposing a chemically stable thioxanthene‐9‐ol to trifluoroacetic acid (TFA). The intensely colored thioxanthylium cations can be chemically reverted to the colorless thioxanthene‐9‐ol. Interestingly, the conversion between thioxanthene‐9‐ol and its cation species was found to be highly reversible in most cases (up to 50 activation‐deactivation cycles). The color and moisture‐sensitivity of thioxanthylium cations were also validated to be tunable via functionalization of the thioxanthene core with different aliphatic and aromatic groups at its 9 or 2,7‐positions. Finally, paper probes were prepared using solution‐immersion and inkjet‐printing techniques to demonstrate the system's potential applications in humidity sensing and anti‐counterfeiting
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Publisher Copyright
Funding Info:
This research / project is supported by the A*STAR - A*STAR 2020 Career Development Fund
Grant Reference no. : C210112042
Description:
This is the peer reviewed version of the following article: Chua, M. H., Soo, X. Y. D., Goh, W. P., Png, Z. M., Zhu, Q., & Xu, J. (2022). Thioxanthylium Cations: Highly Reversible Hydrochromic Mate‐rials with Tunable Color and Moisture Sensitivity. Chemistry – A European Journal, 28(65). Portico. https://doi.org/10.1002/chem.202201975, which has been published in final form at doi.org/10.1002/chem.202201975. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. This article may not be enhanced, enriched or otherwise transformed into a derivative work, without express permission from Wiley or by statutory rights under applicable legislation. Copyright notices must not be removed, obscured or modified. The article must be linked to Wiley’s version of record on Wiley Online Library and any embedding, framing or otherwise making available the article or pages thereof by third parties from platforms, services and websites other than Wiley Online Library must be prohibited