Two-step synthesis and ethanol sensing properties of Zn2SnO4SnO2 nanocomposites

Nearly monodispersed ZnSn(OH)6 nanocubes of about 30 nm in edge length as precursors are hydrothermally prepared in the presence of PVP surfactant. Thermal decomposition of the nanocube precursors at a temperature of 800 °C under inert gas protection leads to the formation of ultrafine nanoparticles of Zn2SnO4-SnO2. The as-produced nanoparticles are roughly spherical and structurally porous. The electrical conductivity measurements demonstrate that thin-film type sensor based on this material has high sensitivity and durability to ethanol, with its optimized sensing properties at a working temperature of 300 °C. Response of the sensor element tends to saturate above an ethanol concentration of 500 ppm.