The Macromolecules Research Group, Department of Chemistry, National University of Colombia, Bogotá 111321, Colombia.
Grupo de Electroquímica y Termodinámica Computacional, Department of Chemistry, National University of Colombia, Bogotá 111321, Colombia.
Sensors (Basel). 2020 Mar 3;20(5):1385. doi: 10.3390/s20051385.
Two Covalent Organic Frameworks (COF), named TFP-BZ and TFP-DMBZ, were synthesized using the imine condensation between 1,3,5-triformylphloroglucinol (TFP) with benzidine (BZ) or 3,3-dimethylbenzidine (DMBZ). These materials were deposited, such as films over interdigitated electrodes (IDE), by chemical bath deposition, giving rise to TFP-BZ-IDE and TFP-DMBZ-IDE systems. The synthesized COFs powders were characterized by Powder X-Ray Diffraction (PXRD), Fourier Transform Infrared spectroscopy (FT-IR), solid-state Nuclear Magnetic Resonance (ssNMR), nitrogen adsorption isotherms, Scanning Electron Microscopy (SEM), and Raman spectroscopy, while the films were characterized by SEM and Raman. Ammonia and low molecular weight amine sensing were developed with the COF film systems using the impedance electrochemical spectroscopy (EIS). Results showed that the systems TFP-BZ-IDE and TFP-DMBZ-IDE detect low molecular weight amines selectively by impedimetric analysis. Remarkably, with no significant interference by other atmospheric gas compounds such as nitrogen, carbon dioxide, and methane. Additionally, both COF films presented a range of sensitivity at low amine concentrations below two ppm at room temperature.
两种共价有机框架（COF），分别命名为 TFP-BZ 和 TFP-DMBZ，是通过 1,3,5-均苯三甲醛（TFP）与联苯（BZ）或 3,3-二甲基联苯（DMBZ）之间的亚胺缩合反应合成的。这些材料通过化学浴沉积在叉指电极（IDE）上沉积成膜，得到 TFP-BZ-IDE 和 TFP-DMBZ-IDE 体系。合成的 COF 粉末通过粉末 X 射线衍射（PXRD）、傅里叶变换红外光谱（FT-IR）、固态核磁共振（ssNMR）、氮气吸附等温线、扫描电子显微镜（SEM）和拉曼光谱进行了表征，而薄膜则通过 SEM 和拉曼进行了表征。使用阻抗电化学光谱法（EIS），用 COF 薄膜系统开发了对氨气和低分子量胺的传感。结果表明，TFP-BZ-IDE 和 TFP-DMBZ-IDE 系统通过阻抗分析选择性地检测低分子量胺。值得注意的是，在室温下，在低于 2ppm 的低胺浓度下，这两种 COF 薄膜都表现出一定的灵敏度。
