Ecofriendly synthesis of tunable silver copper nanoparticles supported on silica for carbon monoxide free hydrogen production from formic acid

The extremely small size and high surface energy of metal nanoparticles (NPs) sometimes lead to their agglomeration, thereby lowering the catalytic performance. This issue is resolved by using a support that enhances dispersion, reduces NPs’ aggregation, and facilitates catalyst separation at the end of the reaction. The present study depicts the facile and eco-friendly synthesis of Ag-Cu/SiO 2 catalysts via a reduction approach. Ultraviolet-visible (UV-vis) spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX) were used to confirm successful synthesis and to perform morphological and compositional analyses of the catalyst. The as-prepared catalysts with different molar ratios were examined for the hydrogen evolution reaction (HER) by catalytic dehydrogenation of formic acid (FA). The Ag 9 Cu 1 /SiO 2 catalyst exhibited the highest catalytic activity, achieving a TOF of 2724 h − 1 at 90 °C together with an activation energy of 31.3 ± 1.46 kJ mol − 1 . These findings open a new path towards the rational synthesis of highly active and robust noble-metal heterogeneous catalysts for CO-free hydrogen production from FA, for use in sustainable energy and fuel cell technologies, and for pollution control.