Semiconducting polymers based on tetraizoindole

The growing interest in the production of electronic devices are able to detect very small amounts of cellular second-messengers as NO or for monitoring gases as NO2, O2, CO2, Cl2 or other toxic gases. The metal-complex tetraizoindoles (metal phthalocyanines, MePcs) were previously shown as potential sensor materials for nitrogen oxide-sensing devices. The synthesis of nickel phthalocyanines (NiPcs), copper polyphthalocyanines (CuPcs) and aliphatic amines-condensed CuPc derivatives are described. Three new aliphatic amine-condensed CuPc derivatives as n-type organic semiconductors were obtained using an original technique conventionally used for aromatic derivatives synthesis. NiPc and aliphatic amine-substituted CuPc derivatives were deposited onto glass substrates by a high-vacuum thermal evaporation technique. Microscopic studies (interference) show that thin films of vapor-deposited MePcs had a thickness of 89–220 nm. The optical properties of MePc thin films have been examined by UV–Vis and IR spectrometry and the effect of NOx upon optical properties is in course. The sensor could be prepared by deposition of MePc thin films on a substrate with IPID (in-plane interdigitated) electrodes for the detection of NO2. The final goal of this paper was to extend both the knowledge on the synthesis of organic metal-complex tetraizoindoles and their potential use as semiconductors in NOx sensing devices.