Deposition of organic metalocomplexes for sensor applications by MAPLE

Complexes of metals with organic ligands are known to be widely used materials for active layers of chemical gas sensors. Among these materials especially those containing a system of conjugated double bonds in ligands have suitable properties for gas sensing. This article deals with deposition and characterization of three materials commonly used in detection of oxidizing gases: indium acetylacetonate (InAcAc), nickel phthalocyanine (NiPc) and copper(II) para-tetratolylmethylporphyrine (CuTTMP). The layers are deposited by a non-conventional matrix-assisted pulsed laser evaporation (MAPLE) method. The choice of a proper matrix and investigation of the deposition rate versus energy density dependence are made. Prepared layers are characterized by Raman spectra and also by measuring their responses to oxidizing gases. The best dc-gas-response was exhibited with an InAcAc layer (S ∼ 10–100 ppb of ozone at 100–160 °C and S ∼ 8–1 ppm of NO2 at 230 °C).