Copper-doped ZnO Gas Sensor Applications
Keywords:
Gas sensor, Na-CMC, NO2 gas, Sensing application, Thin filmsAbstract
In the present study, zinc oxide thin films doped with copper are synthesized through the sol-gel dip-coating technique, followed by thermal treatment at 350°C. Dip coating is selected as the deposition method for film preparation. The resulting copper-incorporated films are then examined to evaluate their structural and surface morphological characteristics. Field emission scanning electron microscopy is used to examine the surface features of the copper-incorporated ZnO thin films and to identify their optimal morphology. Thereafter, crystallographic analysis using X-ray diffraction and compositional evaluation through EDAX are performed on the Cu-doped ZnO films, followed by an assessment of their electrical resistivity. In the final stage, the nitrogen dioxide sensing performance of the copper-doped ZnO thin films is evaluated, with particular emphasis on response and recovery characteristics. This approach is anticipated to yield superior performance, enabling the fabricated films to function efficiently as gas-sensing materials. Sodium carboxymethyl cellulose (Na-CMC) is employed as a viscosity-modifying agent during solution preparation. The results demonstrate that copper-doped films incorporating Na-CMC and fabricated using the sol–gel dip-coating technique display outstanding catalytic activity toward NO₂ gas detection.
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