A role of Au-content in performance of Pd-Au/SiO2 and Pd-Au/Al2O3 catalyst in the hydrogen and oxygen recombination reaction. The microcalorimetric and DFT studies

•Hydrogen and oxygen reaction on Al2O3 and SiO2 supported Pd, Pd-Au catalysts.•Activity and deactivation studied by microcalorimetric technique.•The Pd-Au/SiO2 of low Au content is the most stable under reaction.•The Au vs Pd location affects catalyst deactivation due to O-containing reagents.