Size?Dependent Catalytic Behavior of Gold Nanoparticles

Gold nanoparticles (AuNP) are widely used for reaction catalysis. The common understanding is that the smaller particles, more reactive they are. It reported here this not always case citrate (Ct) or polyvinylpyrrolidone (PVP) stabilized AuNP in catalytic reduction of 4-nitrophenol with sodium borohydride (NaBH4), when total surface area kept constant. results prove size range 10–58 nm, reactivity increases increasing particle diameter investigated model reaction. trend activity independent conjugated ligands and PVP ligands. Purely based on resulting area, unexpected. Only a detailed structural investigation revealed internal structure parameters like defect tendency also play strong role. Larger possess defects between crystalline domains. Further, influence ligand density diffusion effect reactants excluded nitrophenol reduction.