Nanostructured CdO doped MnO2 Thick Film Resistors as Ethanol Sensors

Abstract

The disc type ultrasonicated microwave assisted centrifuge technique was used for the synthesis of nanostructured pure and CdO doped MnO2 powders. The dry powders of as synthesized materials were transformed into thick films by screen printing technique. Synthesized stoichiometric pure MnO2 was observed to be less sensitive to hazardous, toxic and inflammable gases, though they are of nanoscaled. Doping of CdO in MnO2 results in enhancing the gas sensing performance to ethanol. It was observed that, the ethanol response of 3 wt% CdO doped MnO2 thick films, increase crucially at 250oC. It was also observed that, further increase in doping concentration would leads to decrease the gas response. Various characterization techniques were employed to study the surface morphology, structure of the crystal, phases, particle’s size, etc. Effect of the surface nanostructure, different gases, gas concentrations, particle size, long duration for ageing, etc. on the gas response of the samples were studied and discussed. The quick response and fast recovery are the main features of this sensor.