Unraveling the impact of phosphate doping on surface properties and catalytic activity of gold supported on mixed iron-niobium oxide in gas phase methanol oxidation

[Display omitted] •Fe-Nb mixed oxide doped with phosphate is a promising support for gold catalysts.•Phosphate species play a role of structural and electronic modifier.•Phosphate doping increases the electron mobility and improves surface acidity.•Au/P:FeNbOx is much more active in MeOH oxidation than a phosphate-free sample.•Close proximity of centers for MeOH chemisorption and O2 activation in Au/P:FeNbOx. In recent decades, there has been notable interest in understanding the influence of the support composition on the reactivity of gold species in oxidation processes. This study fits in with this scientific trend and investigates the effects of incorporating phosphate ions into Au catalysts supported on mixed iron-niobium oxides in methanol oxidation. All materials were thoroughly characterized using XRD, ICP-OES, DR-UV-Vis, N2 physisorption, HRTEM, HAADF-STEM, SEM-EDX, XPS, TPD-NH3, TPD-CO2, and in situ FTIR combined with adsorption of NO. Activity of the catalysts was evaluated using a fixed-bed flow reactor combined with gas chromatography and operando FTIR-MS system. It was observed that the phosphate-doped catalyst supported on mixed Fe-Nb oxide exhibited significantly higher activity than phosphate-free sample. This improvement resulted from increased electron mobility, enhanced acidity, and optimized distribution of gold nanoparticles on the former catalyst. Knowledge resulting from this work can lead to the development of more efficient gold catalysts.