To summarize, we have developed a very simple technique to
fabricate nanostructured ZnO for chemical sensors. We have
synthesized the structure by means of electrochemical anodization
of metallic thin films at room temperature followed by thermal
annealing at 400 1C. The structural and morphological analysis
showed that the obtained ZnO is a polycrystalline structure in
shape of nanoparticles with the diameter of 25 nm. Absorptiondesorption
mechanism in presence of reducing and oxidizing
gases affects the conductance of ZnO. The conductance of
synthesized ZnO increases upon interaction with reducing gases
and it decreases in presence of oxidizing gases, a typical behavior
of an n-type semiconductor. The nanosized structure demonstrated
high response to NO2, H2, and CH4. The response of the
obtained structure towards NO2 and CH4 strongly depends on its
operating temperature. The response to CH4 increases with the
increase in working temperature, while the response to NO2
decreases as a function of the operating temperature. The samples
show an optimal response towards H2 at 400 1C. The facile
fabrication method and sensing properties of the obtained ZnO
nanostructures is promising for the fabrication of sensor devices