K. Muthumalai, Mathankumar Manoharan, Kamaraj Govindharaj, Poovarasan Saravanan, Yuvaraj Haldorai, Zdeněk Sofer and Ramasamy Thangavelu Rajendra Kumar*,
{"title":"Development of Dual-Selective Chemiresistive Sensor for NH3 and NOx at Room Temperature Using MoS2/MoO2 Heterostructures","authors":"K. Muthumalai, Mathankumar Manoharan, Kamaraj Govindharaj, Poovarasan Saravanan, Yuvaraj Haldorai, Zdeněk Sofer and Ramasamy Thangavelu Rajendra Kumar*, ","doi":"10.1021/acsanm.4c01701","DOIUrl":null,"url":null,"abstract":"<p >Molybdenum oxides and sulfides stand out as promising materials for chemiresistive gas sensors. In this study, we tailored MoS<sub>2</sub>/MoO<sub>2</sub> heterostructures, adapting pyrolysis-assisted in situ sulfidation of hydrothermally grown MoO<sub>3</sub> by tuning the concentration of the sulfur source. The MoS<sub>2</sub> flakes adorning a MoO<sub>2</sub> cuboid rod heterostructure represent the n-type semiconducting property, confirmed by Hall measurement. Notably, the sensor demonstrated dual selectivity toward NH<sub>3</sub> and NO<sub><i>x</i></sub> at room temperature. To our knowledge, the dual selectivity of the MoS<sub>2</sub>/MoO<sub>2</sub> heterostructure has not been reported previously. The heterostructure, characterized by a higher carrier concentration, displayed enhanced sensitivity, yielding responses of 10.3 and 8.4% to 10 ppm of NH<sub>3</sub> and NO<sub><i>x</i></sub>, respectively. The lowest detection limits were 0.32 ppm for NH<sub>3</sub> and 0.29 ppm for NO<sub><i>x</i></sub>. Furthermore, the heterostructure sensor exhibited commendable cyclic stability and device reproducibility. A long-term stability assessment over 50 days revealed that the response of the sensor remained at 98.6 and 98.4% toward NH<sub>3</sub> and NO<sub><i>x</i></sub>, respectively. Our results show that the optimized n–n heterojunction between MoO<sub>2</sub> and MoS<sub>2</sub> offers superior sensitivity to NH<sub>3</sub> and NO<sub><i>x</i></sub> at room temperature. The results could have potential for the development of dual gas sensors suitable for real-time applications.</p>","PeriodicalId":6,"journal":{"name":"ACS Applied Nano Materials","volume":null,"pages":null},"PeriodicalIF":5.3000,"publicationDate":"2024-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"ACS Applied Nano Materials","FirstCategoryId":"88","ListUrlMain":"https://pubs.acs.org/doi/10.1021/acsanm.4c01701","RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATERIALS SCIENCE, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
Molybdenum oxides and sulfides stand out as promising materials for chemiresistive gas sensors. In this study, we tailored MoS2/MoO2 heterostructures, adapting pyrolysis-assisted in situ sulfidation of hydrothermally grown MoO3 by tuning the concentration of the sulfur source. The MoS2 flakes adorning a MoO2 cuboid rod heterostructure represent the n-type semiconducting property, confirmed by Hall measurement. Notably, the sensor demonstrated dual selectivity toward NH3 and NOx at room temperature. To our knowledge, the dual selectivity of the MoS2/MoO2 heterostructure has not been reported previously. The heterostructure, characterized by a higher carrier concentration, displayed enhanced sensitivity, yielding responses of 10.3 and 8.4% to 10 ppm of NH3 and NOx, respectively. The lowest detection limits were 0.32 ppm for NH3 and 0.29 ppm for NOx. Furthermore, the heterostructure sensor exhibited commendable cyclic stability and device reproducibility. A long-term stability assessment over 50 days revealed that the response of the sensor remained at 98.6 and 98.4% toward NH3 and NOx, respectively. Our results show that the optimized n–n heterojunction between MoO2 and MoS2 offers superior sensitivity to NH3 and NOx at room temperature. The results could have potential for the development of dual gas sensors suitable for real-time applications.
期刊介绍:
ACS Applied Nano Materials is an interdisciplinary journal publishing original research covering all aspects of engineering, chemistry, physics and biology relevant to applications of nanomaterials. The journal is devoted to reports of new and original experimental and theoretical research of an applied nature that integrate knowledge in the areas of materials, engineering, physics, bioscience, and chemistry into important applications of nanomaterials.