Sensing of carbon monoxide gas in reducing environments

The change in resistance of thin-films of CuCl upon exposure to carbon monoxide is developed as the basis for sensing CO gas in reducing environments. Several methods of preparation of thin films of CuCl films were examined. Films prepared by solvent evaporation under ambient conditions showed good sensitivity for CO in the presence of hydrogen gas. The optimum sensing temperature was found to be 50 °C. We propose a hole conduction mechanism for CO sensing by CuCl films.