A 4+3 <i>β</i> ‐Ketoenamine‐Linked Covalent Organic Framework Membrane for High‐Performance Film‐Based Fluorescent NO <sub>2</sub> Sensor
Abstract
Abstract Developing compact and structurally simple sensors for reliable and rapid monitoring of nitrogen dioxide (NO 2 ) remains a challenge. In this study, we synthesized a novel β ‐ketoenamine‐linked 4 + 3 covalent organic framework (COF) membrane with unique topology structure using tetrakis(4‐aminophenyl)ethene (ETTA) and 1,3,5‐triformylphloroglucinol (TP) as monomers through liquid‐liquid interfacial polymerization. The sensitive NO 2 response of the ETTA‐TP COF membrane enables the creation of the first and high‐performance NO 2 film‐based fluorescent sensor, achieving fastest response/recovery time (1.5 s/2.0 s) and a high selectivity (over 16 potential interferents). This sensor realizes a low detection limit of 0.1 ppm and a broad detection range from 0.1 to 50 ppm, while maintaining stable performance over 5000 continuous tests. Furthermore, it demonstrates on‐site, real‐time monitoring of NO 2 emissions from automotive exhaust and waste incineration. The sensing mechanism studies reveal that the carbonyl groups of β ‐ketoenamine structure can bind NO 2 via electrostatic interactions and undergoes an energy‐level‐matching photoinduced electron transfer process under photoexcitation. The responses of other carbonyl‐containing fluorescent molecules and COF materials to NO 2 corroborate the generality of this mechanism. This study offers valuable insights into the development of oxidizing gas sensors characterized by fast response time, high sensitivity, and robust in situ online monitoring capabilities.
Article Details
Authors (13)
Xiangquan Liu
Key Laboratory of Applied Surface and Colloid Chemistry of Ministry of Education, School of Chemistry and Chemical Engineering, Shaanxi Key Laboratory of New Concept Sensors and Molecular Materials Shaanxi Normal University Xi'an 710119 P.R. China
Zhicong Zhang
State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000 P.R. China
Lingya Peng
Jinglun Yang
Department of Materials Science and Engineering
Yan Jiang
Experimental Center for Advanced Materials, School of Materials Science and Engineering
Rongrong Huang
Fluorescence Research Group, Singapore University of Technology and Design, 8 Somapah Road, Singapore 487372, Singapore
Yan Luo
Laboratory of Advanced Materials, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, State Key Laboratory of Porous Materials for Separation and Conversion, Fudan University, 220 Handan, Shanghai 200433, P. R. China
Dongxu Xue
Key Laboratory of Applied Surface and Colloid Chemistry of Ministry of Education, School of Chemistry and Chemical Engineering, Shaanxi Key Laboratory of New Concept Sensors and Molecular Materials Shaanxi Normal University Xi'an 710119 P.R. China
Sanyuan Ding
State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000 P.R. China
Daqiang Yuan
State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter
Xiaoyan Liu
Liping Ding
Yu Fang