Nanocomposites and nanomaterials

Effect of morphology of SnO2 nanostructures on their sensing properties to H2
S.V. Nahirniak1, T.A. Dontsova1
1Department of Chemistry, National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute”, Prospect Peremogy 37, Kiev-03056, Ukraine. 
E-mail: nagirnyak_sv@ukr.net

Tin (IV) oxide nanostructures were synthesized by chemical vapor deposition method from tin (II) oxalate in nitrogen atmosphere. Obtaining of structures of different morphology, round-shaped (0DSnO2) and wire-liked (1DSnO2), was achieved by varying synthesis conditions, in particular precursor type and heating rate of furnace [1].
To study the influence of morphology on sensor respond, obtained samples were tested in the presence of different hydrogen concentrations in the range 1000-10000 ppm. As can be seen from Fig. 1, the sensor response slightly increased with the increasing of H2 concentration and reached constant values at 4000 ppm. The sensitivity strongly depends on the morphology of tin (IV) oxide nanostructures. The values of sensitivity of 1DSnO2 sample increases from 60 till 80 with increasing of hydrogen concentration, while sensor respond of 1DSnO2 sample is in the range 20-40. Thus, wire-like sample characterized by almost twice higher sensitivity values and more preferable in the use as gas sensing layers.

Fig. 1 Sensor respond of SnO2 nanostructures to hydrogen at 50 ˚C

1.	Dontsova T.A., Nagirnyak S.V., Zhorov V.V., Yasiievych Y.V. SnO2 nanostructures: effect of processing parameters on their structural and functional properties // NanoScale Research Letters. – 2017. – 12:332 – P. 1-7.