Title: | GC-like Graphene-Coated Quartz Crystal Microbalance Sensor with Microcolumns |
Author(s): | Son J; Ji S; Kim S; Kim S; Kim SK; Song W; Lee SS; Lim J; An KS; Myung S; |
Address: | "Thin Film Materials Research Center, Korea Research Institute of Chemical Technology (KRICT), Daejeon 305-600, Republic of Korea. Department of Chemical Engineering, Hannam University, Daejeon 34430, Republic of Korea" |
Journal Title: | ACS Appl Mater Interfaces |
ISSN/ISBN: | 1944-8252 (Electronic) 1944-8244 (Linking) |
Abstract: | "Many research groups have been interested in the quartz crystal microbalance (QCM)-based gas sensors due to their superb sensitivity originated from direct mass sensing at the ng level. Despite such high sensitivities observed from QCM sensors, their ability to identify gas compounds still needs to be enhanced. Herein, we report a highly facile method that utilizes microcolumns integrated on a QCM gas-responsive system with enhanced chemical selectivity for sensing and ability to identify volatile organic compound single gases. Graphene oxide (GO) flakes are coated on the QCM electrode to substantially increase the adsorption of gas molecules, and periodic polydimethylsiloxane microcolumns with micrometer-scale width and height were installed on the GO-coated QCM electrode. The observed frequency shifts upon sensing of various single gas molecules (such as ethanol, acetone, hexane, etc.) can be analyzed accurately using a simple exponential model. The QCM sensor system with and without the microcolumn both exhibited high detection response values above 50 ng/cm(2) for sensing of the gases. Notably, the QCM sensor equipped with the microcolumn features gas identification ability, which is observed as distinct diverging behavior of time constants upon detection of different gases caused by the difference in diffusional transfer of molecules through the microcolumns. For example, the difference in the calculated time constant between ethanol and acetone increased from 22.6 to 92.1 s after installation of the microcolumn. This approach provides an easy and efficient method for identification of single gases, and it may be applied in various advanced sensor systems to enhance their gas selectivity" |
Keywords: | chemical sensor gas chromatography microcolumn quartz crystal microbalance single-gas sensor; |
Notes: | "PubMed-not-MEDLINESon, Jieun Ji, Seulki Kim, Sungho Kim, Soyoung Kim, Seong K Song, Wooseok Lee, Sun Sook Lim, Jongsun An, Ki-Seok Myung, Sung eng 2021/01/14 ACS Appl Mater Interfaces. 2021 Jan 27; 13(3):4703-4710. doi: 10.1021/acsami.0c19010. Epub 2021 Jan 13" |