A Micropowered Chemoresistive Sensor Based on a Thin Alumina Nanoporous Membrane and Sn(x)Bi(k)Mo(y)O(z) Nanocomposite

This work presents and discusses the design of an efficient gas sensor, as well as the technological process of its fabrication. The optimal dimensions of the different sensor elements including their deformation were determined considering the geometric modeling and the calculated moduli of the elasticity and thermal conductivity coefficients. Multicomponent Sn(x)Bi(k)Mo(y)O(z) thin films were prepared by ionic layering on an anodic alumina membrane and were used as gas-sensitive layers in the sensor design. The resistance of the Sn(x)Bi(k)Mo(y)O(z) nanostructured film at temperatures up to 150 °C exceeded 10(6) Ohm but decreased to 10(4) Ohm at 550 °C in air. The sensitivity of the Sn(x)Bi(k)Mo(y)O(z) composite to concentrations of 5 and 40 ppm H(2) at 250 °C (10 mW) was determined to be 0.22 and 0.40, respectively.