Electrophoretic Deposition of SnO2 Nanoparticles and Its LPG Sensing Characteristics

Abstract

Homogenized SnO<inf>2</inf> nanoparticles (60 nm) in acetylacetone mediums, both with and without iodine, were deposited onto platinum coated alumina substrate and interdigital electrodes using the electrophoretic deposition (EPD) method for gas sensor applications. Homogeneous and porous film layers were processed and analyzed at various coating times and voltages. The structure of the deposited films was characterized by a scanning electron microscopy (SEM). The gas sensing properties of the SnO<inf>2</inf> films were investigated using liquid petroleum gas (LPG) for various lower explosive limits (LEL). The results showed that porous, crack-free, and homogeneous SnO<inf>2</inf> films were achieved for 5 and 15 sec at 100 and 150 V EPD parameters using an iodine-free acetylacetone based SnO<inf>2</inf> suspension. The optimum sintering for the deposited SnO<inf>2</inf> nanoparticles was observed at 500°C for 5 min. The results showed that the sensitivity of the films was increased with the operating temperature. The coated films with EPD demonstrated a better sensitivity for the 20 LEL LPG concentrations at a 450°C operating temperature. The maximum sensitivity of the SnO<inf>2</inf> sensors at 450°C to 20 LEL LPG was 30. © 2015 Göktuʇ Günkaya et al.