| Title: | Highly Selective Chloromethanes Detection Based on Quartz Crystal Microbalance Gas Sensors with Ba-MOFs |
| Author(s): | Liu Y; Fan Y; Hou C; Du W; Zhang D; Liu Y; Xu J; Bai YL; |
| Address: | "NEST Lab, Department of Chemistry, College of Sciences, Shanghai University, Shanghai 200444, P.R. China. International Center for Quantum and Molecular Structures, College of Sciences, Shanghai University, Shanghai 200444, P.R. China" |
| DOI: | 10.1021/acs.inorgchem.1c02185 |
| ISSN/ISBN: | 1520-510X (Electronic) 0020-1669 (Linking) |
| Abstract: | "Three new metal-organic frameworks (MOFs), (CH(3)NH(3))(3)[Ba(2)(TTHA)(NO(3))(H(2)O)(2)].2H(2)O (1), (CH(3)NH(3))(4)[Ba(3)(HTTHA)(2)(H(2)O)(7)].3H(2)O (2), and [Ba(7)(TTHA)(2)(NO(3))(2)(H(2)O)(10)].2H(2)O (3) (H(6)TTHA = 1,3,5-triazine-2,4,6-triamineh-exaacetic acid) have been synthesized and characterized. The sensing properties of 1-3 were explored with regard to volatile organic compounds (VOCs) by the quartz crystal microbalance (QCM) technique. The results indicated that 1 and 2 have a much higher selectivity and response to chloromethanes (CH(2)Cl(2), CHCl(3), and CCl(4)) compared with H(2)O, CH(3)OH, CH(3)CH(2)OH, CH(3)CN, (CH(3))(2)CO, C(6)H(6), C(6)H(5)CH(3), C(6)H(5)CH(2)CH(3), and C(6)H(5)Cl at room temperature. Furthermore, 1 and 2 sensing film also exhibits excellent reversibility and stability, and the response and recovery times are almost within 10 s. 3 displays a lower response and poor selectivity to the above VOCs. The significant difference may be caused by their different structural characteristics. The Ba(2+) ions are all decacoordinated in 1 and 2, while Ba(2+) ions have more open metal sites in 3. So, the high selectivity and response of 1 and 2 may be due to the exchange of coordination water molecules with chloromethanes and possible electrostatic effects between (CH(3)NH(3))(+) cations and chloromethanes containing more electronegative Cl atoms. DFT calculation results show that the bond energy of Ba-Cl and Ba-O is not much different, so chloromethanes at high concentrations may exchange coordination water to form weak Ba...Cl interactions and show higher response values. 3 has no obvious VOCs selectivity and higher response due to more open sites of Ba(2+) ions and smaller pore size. This work develops a fast and effective method to detect chloromethanes, providing a new opportunity for designing QCM gas sensors coated with different MOF materials" |
| Notes: | "PubMed-not-MEDLINELiu, Yanan Fan, Yu Hou, Chaoyi Du, Wei Zhang, Dan Liu, Yu Xu, Jiaqiang Bai, Yue-Ling eng 2021/10/23 Inorg Chem. 2021 Nov 1; 60(21):16370-16377. doi: 10.1021/acs.inorgchem.1c02185. Epub 2021 Oct 22" |
