Enhanced CO gas sensing properties of Cu doped SnO2 nanostructures prepared by a facile wet chemical method

Abstract

We report the synthesis of Cu doped SnO₂ nanostructures with enhanced CO gas sensing properties by a facile wet chemical method. The effects of Cu doping on the structural and optical properties of SnO₂ nanostructures were investigated using X-ray diffraction, field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and high resolution TEM (HRTEM) with energy dispersive X-ray spectroscopy, Raman spectroscopy and photoluminescence spectroscopy. FESEM studies revealed the presence of nanosheets and nanodisc-like structures in Cu doped SnO₂ samples. Gas sensing studies showed that the sensor prepared using 1% Cu doped SnO₂ nanostructures exhibits highly enhanced CO gas sensing properties as compared to pure SnO₂ nanostructures and shows excellent selectivity for CO with negligible interference from CH₄, CO₂ and NO₂. The possible mechanism for the enhanced CO gas sensing properties of Cu doped SnO₂ nanostructures is proposed.