| Title: | Sulfur-Doped Titanium Carbide MXenes for Room-Temperature Gas Sensing |
| Author(s): | Shuvo SN; Ulloa Gomez AM; Mishra A; Chen WY; Dongare AM; Stanciu LA; |
| Address: | "Purdue University, West Lafayette, Indiana 47907, United States. University of Connecticut, Storrs, Connecticut 06269, United States. Birck Nanotechnology Center, West Lafayette, Indiana 47907, United States" |
| DOI: | 10.1021/acssensors.0c01287 |
| ISSN/ISBN: | 2379-3694 (Electronic) 2379-3694 (Linking) |
| Abstract: | "Two-dimensional titanium carbide MXenes, Ti(3)C(2)T(x), possess high surface area coupled with metallic conductivity and potential for functionalization. These properties make them especially attractive for the highly sensitive room-temperature electrochemical detection of gas analytes. However, these extraordinary materials have not been thoroughly investigated for the detection of volatile organic compounds (VOCs), many of which hold high relevance for disease diagnostics and environmental protection. Furthermore, the insufficient interlayer spacing between MXene nanoflakes could limit their applicability and the use of heteroatoms as dopants could help overcome this challenge. Here, we report that S-doping of Ti(3)C(2)T(x) MXene leads to a greater gas-sensing performance to VOCs compared to their undoped counterparts, with unique selectivity to toluene. After S-doped and pristine materials were synthesized, characterized, and used as electrode materials, the as-fabricated sensors were subjected to room-temperature dynamic impedimetric testing in the presence of VOCs with different functional groups (ethanol, hexane, toluene, and hexyl-acetate). Unique selectivity to toluene was obtained by both undoped and doped Ti(3)C(2)T(x) MXenes, but an enhancement of response in the range of approximately 214% at 1 ppm to approximately 312% at 50 ppm (3-4 folds increase) was obtained for the sulfur-doped sensing material. A clear notable response to 500 ppb toluene was also obtained with sulfur-doped Ti(3)C(2)T(x) MXene sensors along with excellent long-term stability. Our experimental measurements and density functional theory analysis offer insight into the mechanisms through which S-doping influences VOC analyte sensing capabilities of Ti(3)C(2)T(x) MXenes, thus opening up future investigations on the development of high-performance room-temperature gas sensors" |
| Keywords: | Electrodes *Sulfur Temperature *Titanium MXenes chemi-resistive gas sensors interdigitated electrodes scanning/transmission electron microscopy volatile organic compounds; |
| Notes: | "MedlineShuvo, Shoumya Nandy Ulloa Gomez, Ana Maria Mishra, Avanish Chen, Winston Yenyu Dongare, Avinash M Stanciu, Lia A eng 2020/08/14 ACS Sens. 2020 Sep 25; 5(9):2915-2924. doi: 10.1021/acssensors.0c01287. Epub 2020 Aug 25" |
