Nanorods to nanosheets structural evolution of NixZn1-xO for NO2 gas sensing application

• Published in: Journal of alloys and compounds 2018-10, Vol.766, p.941-951
• Main Authors: Jagadale, Supriya B., Patil, Vithoba L., Mali, Sawanta S., Vanalakar, Sharadrao A., Hong, Chang K., Patil, Pramod S., Deshmukh, Harish P.
• Format: Article
• Language: English
• Subjects: Gas sensor; Nanorods; Nanosheets
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2018.07.040

In the present study the efforts are taken to fabricate NixZn1-xO nanostructures (x = 0.04, 0.08, 0.12, 0.16 and 0.2) thin film by simple hydrothermal method. The prepared thin films were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDX), photoluminescence (PL) spectroscopy and two probe resistivity technique. Interestingly, it was found that the morphology of the nanostructures evolved from rod-like to sheet-like structures with variation in the concentration of Ni in ZnO from x = 0.04 to 0.16. The NixZn1-xO thin films of all compositions were tested for the gas sensing behavior for the oxidizing gas; NO2 (Nitrogen dioxide). It is found that, the sensing response increases with increase in the Ni2+ concentration up to x = 0.16, and then it decreases slightly for further increment in Ni2+. The Ni0.16Zn0.84O film shows higher response (S) = 9.01 for 8 ppm NO2 at comparatively low operating temperature. Additionally, NixZn1-xO thin film sensor has potentially detected 1 ppm of NO2 gas with admirable response ∼1.45. [Display omitted] •Effect of morphology evolution nanorods to nanosheets on NO2 gas sensing was studied.•Ni incorporation increases oxygen vacancy related defect to adsorb NO2 gas molecules.•High selectivity and response towards NO2 below TLV observed for evolved nanosheets.