We have developed a process for preparation of composites by blending and ultrasonification of multi-walled carbon nanotubes with metal-phthalocyanines and have used the same as very selective and sensitive sensor for detection of H(2)O(2) vapors. A combination of sensors made from composites of cobalt-phthalocyanine and copper-phthalocyanine with multiwall carbon nanotubes has been found to show opposite conductivities to H(2)O(2) vapors while the pair shows similar response to other chemical vapors. This unusual behavior makes this paired sensor as a reliable method to selectively identify the presence of H(2)O(2) vapors with response and recovery times of few seconds. Our developed sensors work at room temperature and show resistivity in the range of 10(4) to 10(5) Omega cm. They can be employed for detection of H(2)O(2) based explosives, to monitor levels of H(2)O(2) in industrial units and other applications. (C) 2011 Elsevier B.V. All rights reserved.