Towards Low Temperature Operation of Catalytic Gas Sensors: Mesoporous CoO-Supported Au-Pd Nanoparticles as Functional Material.

It is shown that the operating temperature of pellistors for the detection of methane can be reduced to 300 °C by using Au-Pd nanoparticles on mesoporous cobalt oxide (Au-Pd@meso-CoO). The aim is to reduce possible catalyst poisoning that occurs during the high-temperature operation of conventional Pd-based pellistors, which are usually operated at 450 °C or higher. The individual role of Au-Pd as well as CoO in terms of their catalytic activity has been investigated.

Screen-Printed Sensors for Colorimetric Detection of Hydrogen Sulfide in Ambient Air.

A fast and sensitive method to monitor hydrogen sulfide (H₂S) in ambient air based on a visible color change of a printed disposable sensor has been developed. As gas-sensitive material, an immobilized copper(II) complex of the azo dye 1-(2-pyridylazo)-2-naphtol (H-PAN) was synthesized and prepared in an ethyl cellulose matrix for screen printing. If H₂S is present in ambient air, the gas sensitive layer changes its color from purple to yellow.

Investigation of Gasochromic Rhodium Complexes Towards Their Reactivity to CO and Integration into an Optical Gas Sensor for Fire Gas Detection.

The detection of the toxic gas carbon monoxide (CO) in the low ppm range is required in different applications. We present a study of the reactivity of different gasochromic rhodium complexes towards the toxic gas carbon monoxide (CO). Therefore, variations of binuclear rhodium complexes with different ligands were prepared.

New energetic materials: functionalized 1-ethyl-5-aminotetrazoles and 1-ethyl-5-nitriminotetrazoles.

Alkylation of 5-aminotetrazole (1) with 2-chloroethanol leads to a mixture of the N-1 and N-2 isomers of (2-hydroxyethyl)-5-aminotetrazole. Treatment of 1-(2-hydroxyethyl)-5-aminotetrazole (2) with SOCl(2) yielded 1-(2-chlorethyl)-5-aminotetrazole (3). 1-(2-Azidoethyl)-5-aminotetrazole (4) was generated by the reaction of 3 with sodium azide.