Fabrication of SnO 2 particle-layer on the glass substrate using electrospray pyrolysis method and the gas sensitivity for H 2

Abstract

The tin-dioxide particle-layer is deposited on the pyrex glass substrate using the electrospray pyrolysis (ESP) method. The solution concentrations examined are 1×10 −4, 1×10 −3, and 1×10 −2 mol dm −3. The layer thickness increases linearly with spray time. At 1×10 −3 mol dm −3, the deposition rate is 0.40 (4) μm h −1. The layer thickness is determined by the amount of solute sprayed on the substrate. The sizes of the composing particles in the scanning electron microscope (SEM) observation are 110 (30), 160 (40), and 150 (35) nm at 1×10 −4, 1×10 −3, and 1×10 −2 mol dm −3, respectively. The gas sensitivity measurements are carried out for 0.5% H 2 balanced with dry air. The particle-layer deposited from 1×10 −3 mol dm −3 solution exhibits the maximum sensitivity of 20 (4) regardless of the spraying time over 1 h. The sensitivity is independent of the spray time but dependent on the concentration of the solution, in which the precursor concentration is considered to affect the size of crystallites constituting the secondary particles observed in SEM.