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Title: Redox‐Triggered Orientational Responses of Liquid Crystals to Chlorine Gas
Abstract Surface‐supported liquid crystals (LCs) that exhibit orientational and thus optical responses upon exposure to ppb concentrations of Cl2gas are reported. Computations identified Mn cations as candidate surface binding sites that undergo redox‐triggered changes in the strength of binding to nitrogen‐based LCs upon exposure to Cl2gas. Guided by these predictions, μm‐thick films of nitrile‐ or pyridine‐containing LCs were prepared on surfaces decorated with Mn2+binding sites as perchlorate salts. Following exposure to Cl2, formation of Mn4+(in the form of MnO2microparticles) was confirmed and an accompanying change in the orientation and optical appearance of the supported LC films was measured. In unoptimized systems, the LC orientational transitions provided the sensitivity and response times needed for monitoring human exposure to Cl2gas. The response was also selective to Cl2over other oxidizing agents such as air or NO2and other chemical targets such as organophosphonates.  more » « less
Award ID(s):
1435195 1720415
PAR ID:
10063625
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie International Edition
Volume:
57
Issue:
31
ISSN:
1433-7851
Page Range / eLocation ID:
p. 9665-9669
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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