Hydrothermal Synthesis and Gas Sensing Properties of CuO Nanorods

This paper describes a simple method for growing well crystallined rod-like Copper oxide (CuO) nanoparticles by a hydrothermal method. The structure of CuO nanostructure has been examined by X-ray diffraction. Further, Retvield refinement and selected area electron diffraction (SAED) confirm the single phase and monoclinic structure of the CuO nanostructure. Scanning electron microscope and transmission electron microscope observations reveal that the CuO nanostructure is rod-like nature with the length and diameter of about 106 nm and 28 nm, respectively. The optical band gap of the nanorods has been estimated as 2.49 eV using Tauc's plot. Vibrating sample magnetometer analysis confirms that the synthesized nanorods possess weak ferromagnetism. The gas sensing properties of synthesized CuO nanorods have been studied for different gases, viz ammonia, methanol and ethanol from RT, 75 degrees C and 100 degrees C. The sensor responded to all the three gases and exhibited high sensitivity at 75 degrees C. Further, the quick response (8 min) and recovery (9 min) times have been observed for methanol at room temperature compared to other two gases.