Highly Sensitive NO 2 Gas Sensors Based on MoS 2 @MoO 3 Magnetic Heterostructure

• Published in: Nanomaterials (Basel, Switzerland) Vol. 12; no. 8
• Main Authors: Li, Wei, Shahbazi, Mahboobeh, Xing, Kaijian, Tesfamichael, Tuquabo, Motta, Nunzio, Qi, Dong-Chen
• Format: Journal Article
• Language: English
• Published: Switzerland 11-04-2022
• Subjects: molybdenum disulfides; nitrogen dioxide; 2D materials; gas sensor; sulfurization; molybdenum trioxide; heterostructure
• ISSN: 2079-4991; 2079-4991

Recently, two-dimensional (2D) materials and their heterostructures have attracted considerable attention in gas sensing applications. In this work, we synthesized 2D MoS
@MoO
heterostructures through post-sulfurization of α-MoO
nanoribbons grown via vapor phase transport (VPT) and demonstrated highly sensitive NO
gas sensors based on the hybrid heterostructures. The morphological, structural, and compositional properties of the MoS
@MoO
hybrids were studied by a combination of advanced characterization techniques revealing a core-shell structure with the coexistence of 2H-MoS
multilayers and intermediate molybdenum oxysulfides on the surface of α-MoO
. The MoS
@MoO
hybrids also exhibit room-temperature ferromagnetism, revealed by vibrating sample magnetometry (VSM), as a result of the sulfurization process. The MoS
@MoO
gas sensors display a
-type-like response towards NO
with a detection limit of 0.15 ppm at a working temperature of 125 °C, as well as superb selectivity and reversibility. This
-type-like sensing behavior is attributed to the heterointerface of MoS
-MoO
where interfacial charge transfer leads to a
-type inversion layer in MoS
, and is enhanced by magnetic dipole interactions between the paramagnetic NO
and the ferromagnetic sensing layer. Our study demonstrates the promising application of 2D molybdenum hybrid compounds in gas sensing applications with a unique combination of electronic and magnetic properties.