Electrophoretic deposition of CuO particulate thick film for ethanol sensing

Detection of volatile organic compounds is of utmost importance in numerous applications such as medical diagnosis, air quality monitoring, hazardous gas detection and food industry. In the present work, investigation on the ethanol-sensing performance of CuO thick film fabricated by electrophoretic deposition (EPD) technique was done. Oval-shaped CuO powder is prepared at room temperature via a facile wet chemical method. A simple, versatile and reproducible electrophoretic deposition technique is employed to fabricate thick film of the as-synthesized CuO powder on to a non-conducting alumina pellet. The sensing performance of EPD-grown thick film CuO sensor has been investigated in static ambient. The uniform and porous sensing layer fabricated by EPD technique exhibits good sensing characteristics such as high response % (~ 129%), quick response (38 s), recovery (462 s) time and stable baseline resistance. For better understanding of sensing performance, theoretical analysis such as stability of the sensing element analysis and response versus temperature simulation were performed. Characteristics constant response time (~ 88 s) is obtained for different test gas concentrations in the range of 50 ppm to 300 ppm. From response versus temperature simulation, activation energies of transduction and first-order kinetics were estimated as 29.43 kJ/mol and 62.99 kJ/mol, respectively.