Ion-in-Conjugation: Squaraine as an Ultrasensitive Ammonia Sensor Material

Xin Xiao; Xue-Feng Cheng; Xiang Hou; Jing-Hui He; Qing-Feng Xu; Hua Li; Na-Jun Li; Dong-Yun Chen; Jian-Mei Lu

doi:10.1002/smll.201602190

Ion-in-Conjugation: Squaraine as an Ultrasensitive Ammonia Sensor Material

Small. 2017 Jan;13(2). doi: 10.1002/smll.201602190. Epub 2016 Oct 18.

Authors

Xin Xiao¹, Xue-Feng Cheng¹, Xiang Hou¹, Jing-Hui He¹, Qing-Feng Xu¹, Hua Li¹, Na-Jun Li¹, Dong-Yun Chen¹, Jian-Mei Lu¹

Affiliation

¹ College of Chemistry, Chemical Engineering and Materials Science, Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou, 215123, P. R. China.

PMID: 27754595
DOI: 10.1002/smll.201602190

Abstract

An organic thin-film gas sensor based on squaraine detects ammonia as low as 40 ppb with impressive reversibility and stability. The resonance-stabilized zwitterionic characteristics offer squaraines high affinity and sensitivity toward electron-rich analytes without irreversible chemical binding, while the embedded squaric ring makes SA-CH₃ highly sensitive. The symmetric molecular geometry and good crystallinity also contribute to the high performance.

Keywords: ammonia sensors; organic thin-film; resonance-stabilized; squaraine; zwitterionic.