Characterization and sensing application of modified multi walled carbon nanotubes/metal phthalocyanine thin films

Abstract

Hybrid materials of multi walled carbon nanotubes with zinc phthalocyanine and aluminum phthalocyanine have been prepared. Multi walled carbon nanotubes were treated with mixture of nitric and sulfuric acid pre to the mixing with phthalocyanines for the de-bundling effect. Hybrid materials have been drop casted onto glass slides and interdigitated electrodes from their solution in dimethylformamide and applied as active layers to detect some vapours (chloroform, ammonia, and nitrogen dioxide). Ultraviolet-visible absorption spectroscopy and Fourier Transform Infrared Spectroscopy have revealed the successful hybridization due rr-rr interaction between modified multi walled carbon nanotubes and phthalocyanine species. Results of gas sensor showed that the hybrid film prepared from modified multi walled carbon nanotubes with zinc phthalocyanine exhibits excellent sensitivity at room temperature upon exposure to ammonia and nitrogen dioxide vapours even at a low concentration of 25ppm, also the central metal in phthalocyanine molecules plays an important role in the determination of the hybrid materials (sensor) performance.