One-Dimensional MoS2-Decorated TiO2 nanotube gas sensors for efficient alcohol sensing

• Published in: Journal of alloys and compounds Vol. 674; pp. 252 - 258
• Main Authors: Zhao, P.X., Tang, Y., Mao, J., Chen, Y.X., Song, H., Wang, J.W., Song, Y., Liang, Y.Q., Zhang, X.M.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 25-07-2016
• Subjects: Gas sensor; MoS2; p-n heterojunction; TiO2 nanotubes; TiO2 nanotubes; Gas sensor; MoS2; p-n heterojunction
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2016.03.029

One-Dimensional (1D) MoS2-decorated TiO2 nanotubes were synthesized by the anodization of TiO2 nanotubes followed by a hydrothermal process for MoS2-decoration. The structure, morphology and surface characteristics of the MoS2-TiO2 composites were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and Brunauer–Emmett–Teller (BET). The results showed that TiO2 nanotubes can be filled and covered by flake-like MoS2 nanostructure. The numbers of the MoS2 layers ranged from 1 to 3. The TiO2 nanotube sensor shows a normal n-type response to reducing ethanol gas, whereas MoS2-TiO2 exhibits p-type response with excellent sensing performances. Specially, the sensitivity for the MoS2-TiO2 heterojunction increased almost 11 times than TiO2 nanotubes. This conversion of sensing behavior can be explained by the formation of p-n heterojunction structures.
•The TiO2 nanotubes were modified by MoS2 nanofalkes using a hydrothermal process.•The MoS2-TiO2 composites possess higher specific surface area than TiO2 nanotubes.•The MoS2-TiO2 composites show excellent sensing performance towards ethanol vapors.•The formation of p-n heterojunction contributes to the high sensing property.