Gas sensing properties of zinc stannate (Zn2SnO4) nanowires prepared by carbon assisted thermal evaporation process.

Zn 2 SnO 4 nanowires are successfully synthesized by a carbon assisted thermal evaporation process with the help of a gold catalyst under ambient pressure. The as-synthesized nanowires are characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM) equipped with an energy dispersive X-ray spectroscopy (EDS). The XRD patterns and elemental mapping via TEM–EDS clearly indicate that the nanowires are Zn 2 SnO 4 with face centered spinel structure. HRTEM image confirms that Zn 2 SnO 4 nanowires are single crystalline with an interplanar spacing of 0.26 nm, which is ascribed to the d-spacing of (3 1 1) planes of Zn 2 SnO 4 . The optimum processing condition and a possible formation mechanism of these Zn 2 SnO 4 nanowires are discussed. Additionally, sensor performance of Zn 2 SnO 4 nanowires based sensor is studied for various test gases such as ethanol, methane and hydrogen. The results reveal that Zn 2 SnO 4 nanowires exhibit excellent sensitivity and selectivity toward ethanol with quick response and recovery times. The response of the Zn 2 SnO 4 nanowires based sensors to 50 ppm ethanol at an optimum operating temperature of 500 °C is about 21.6 with response and recovery times of about 116 s and 182 s, respectively. [ABSTRACT FROM AUTHOR]