Silver and palladium alloy nanoparticle catalysts: reductive coupling of nitrobenzene through light irradiation.

Silver-palladium (Ag-Pd) alloy nanoparticles strongly absorb visible light and exhibit significantly higher photocatalytic activity compared to both pure palladium (Pd) and silver (Ag) nanoparticles. Photocatalysts of Ag-Pd alloy nanoparticles on ZrO and AlO supports are developed to catalyze the nitroaromatic coupling to the corresponding azo compounds under visible light irradiation. Ag-Pd alloy NP/ZrO exhibited the highest photocatalytic activity for nitrobenzene coupling to azobenzene (yield of ∼80% in 3 hours).