Ethanol gas sensing properties of hydrothermally grown α-MnO2 nanorods

• Published in: Journal of alloys and compounds 2017-12, Vol.727, p.362-369
• Main Authors: Liu, Chenshitao, Navale, S.T., Yang, Z.B., Galluzzi, M., Patil, V.B., Cao, P.J., Mane, R.S., Stadler, F.J.
• Format: Article
• Language: English
• Subjects: Gas sensing properties; Hydrothermal synthesis; Metal oxides; MnO2; Nanorods
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2017.08.150

In the present work, nanorods of alpha-manganese dioxide (α-MnO2 NRs) have been successfully synthesized using simple and cost-effective hydrothermal method, which further are utilized as a potential ethanol gas sensing material. As-synthesized α-MnO2 NRs are characterized for their structure and morphology by means of X-ray diffraction, Raman spectroscopy, energy dispersive X-ray spectroscopy, field-emission scanning electron microscopy, transmission electron microscopy, and atomic force microscopy measurement techniques, respectively. Structural elucidation confirms the formation of phase-pure tetragonal α-MnO2. Randomly distributed α-MnO2 NRs demonstrate average diameter of ∼50–60 nm and length ∼1–1.5 μm. Gas sensing properties of α-MnO2 NRs carried out systematically, as a function of time, towards various target gases and operating temperatures, corroborate excellent selectivity towards ethanol at 180 °C as an optimum operating temperature in addition to detect as little as 10 ppm ethanol gas. Furthermore, α-MnO2 NRs sensor shows the superior reproducibility and stability in response upon consecutive exposure of ethanol at 180 °C. Gas sensing study reveals the applicability of α-MnO2 NRs as a promising sensing material in the developing ethanol-based gas sensors. [Display omitted] •Simple and cost-effective hydrothermal synthesis strategy of α-MnO2 NRs.•Structural elucidation supports the formation of phase-pure tetragonal α-MnO2.•Formation of α-MnO2 NRs, ∼50–60 nm in diameter and ∼1–1.5 μm in length, was corroborated through morphological analysis.•As-fabricated α-MnO2 NRs sensor is highly selective to C2H5OH @180 °C.•α-MnO2 NRs sensor exhibit excellent repeatability, and stability in response upon consecutive exposure of C2H5OH @180 °C.