In order to enhance the durability of chemical filters for ozone molecules, devoted to microsystem for the selective detection of NO2 in the environment, the adsorption of indigo molecules onto the surface of carbonaceous nanomaterials (multi-walled carbon nanotubes, a mixture of nanodisks/nanocones, nanofibres) was investigated. The surface of the multi-walled carbon nanotubes was coated by pi-stacking with adsorbed indigo molecules. An excess of indigo has resulted in a biphasic sample where nanotubes covered with indigo coexist with free indigo particles. Although similar filtering yields toward O-3 (close to 100%) and NO2 (around 0%) were obtained as compared to individual materials, the indigo/MWCNTs samples exhibit enhanced durability as chemical filter at high ozone concentration (1 ppm). (C) 2013 Published by Elsevier Inc.