A Benzimidazole-Containing Covalent Organic Framework-Based QCM Sensor for Exceptional Detection of CEES

• DOI: 10.1021/acs.cgd.9b00409
• Publication Date: 2019-05-01T14:59:36Z
• Authors: Zi-Hao He; Shi-Da Gong; Song-Liang Cai; Yi-Lun Yan; Gui Chen; Xin-Le Li; Sheng-Run Zheng; Jun Fan; Wei-Guang Zhang
• Keywords: Quartz Crystal Microbalance; Benzimidazole; Covalent organic framework

Mustard gas poses a substantial concern for homeland security, and the development of sensors facile, rapid, highly sensitive, selective detection mustard simulant is much desirable. Herein, new benzimidazole-containing covalent organic framework (COF), termed BABE-TFPy COF, was synthesized by Schiff base condensation 1-(4,7-bis(4-aminophenyl)-1H-benzoimidazole-2-yl)ethan-1-ol (BABE) with 1,3,6,8-tetrakis(4-formylphenyl)pyrene (TFPy). By virtue its crystallinity, high porosity, excellent chemical stability, abundant accessible benzimidazole sites, an unprecedented COF coated quartz crystal microbalance (QCM) sensor judiciously fabricated various volatile compounds (VOCs). Remarkably, resultant QCM exhibited significantly higher sensitivity to 2-chloroethyl ethyl sulfide (CEES), typical hazardous simulant, than those other common VOCs. Moreover, frequency changes were linearly related concentrations CEES vapor within range 5.6–19.7 ppm, derived strikingly low limit 0.96 ppm (signal-to-noise ratio = 3), rendering it extraordinary CEES. The enthalpy change indicated temperature-varying microgravimetric experiment, along Gaussian theoretical calculation, suggests dual-hydrogen bonding formed between molecule accounts such exceptional recognition