Abstract
In the present work, NiO coated ZnO films have been deposited at various deposition times such as 1, 2, 4 and 8 h using chemical bath deposition (CBD) method. X-ray diffraction (XRD) study showed the presence of both hexagonal ZnO and cubic NiO crystal structures. The field emission scanning electron microscopy (FE-SEM) images reveal the porous hierarchical microflower-like morphology. The atomic force microscopy (AFM) micrographs exhibit a maximum surface roughness of 174 nm. Brunauer Emmett-Teller (BET) shows the higher surface area of 31.41 m2/g. X-ray photoelectron spectroscopy (XPS) study showed the presence of Zn-2p3/2 and Zn-2p1/2 for Zn2+ oxidation state in ZnO whereas Ni-2p3/2 and Ni-2p1/2 for Ni2+ oxidation state in NiO. The NiO coated ZnO film shows the response of 76.5 % to 100 ppm NO2 at working temperature of 150 °C with Tresponse = 12 s and Trecovery = 140 s. Finally, NO2 sensing mechanism is proposed.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
