Investigation of hydrogen sensing properties of graphene/Al-SnO2 composite nanotubes derived from electrospinning

Graphene-based device/sensor made of multifunctional nanomaterials is an emerging technology due to its huge impact on the engineering materials. Herein, we report the synthesis of pristine SnO2, Al-doped SnO2 (Al-SnO2), and graphene-embedded Al-SnO2 (G-Al-SnO2) nanotubes by one-step electrospinning method and studied their physical and gas sensing characteristics. The synthesized tubular structure was confirmed by scanning electron microscope (SEM) and transmission electron microscope (TEM). Structural, chemical binding, pore size, and chemical composition/elemental states were estimated by the X-ray diffraction, Raman, BET, and X-ray photoelectron spectroscopy, respectively. The performance of the gas sensing based on SnO2, Al-SnO2 , and G-Al-SnO2 materials for H-2 detection was investigated, and the G-Al-SnO2 composite nanotubes exhibit the superior sensitivity at 300 degrees C. The sensing response reaches about 23.8 at H-2 concentration of 100 ppm with a shorter response time of about 2.2 s and recovery time of about 1.4 s. The gas sensing performance of the G-Al-SnO2 nanotubes is much better than that of the pristine SnO2 and Al-SnO2 nanotubes, which is probably attributed to the relatively smaller diameter of about 100 nm, better thermal and electronic conductivity, and relatively high oxygen vacancy, induced by graphene and Al-doping. The prepared H-2 sensor is a simple, compact and highly sensitive, which holds high promising in many fields. (C) 2018 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.