Polyol Synthesis of Silver Nanoparticles and Deposition on Carbon Vulcan for 4-Nitrophenol Reduction Catalysis

Silver nanoparticles (AgNP) were synthesized and then immobilized onto Carbon Vulcan support to be used as a catalyst (AgNP/C) for 4-nitrophenol (4-NP) reduction. Polyol method was used for AgNP synthesis with glycerol-water as the solvent mixture, trisodium citrate (TSC) as the reducing agent and the capping agent, silver nitrate as the silver precursor. The optimized reaction conditions were glycerol content of 35% (w/w), temperature of 105 degrees C, reaction time of 120 min, TSC/Ag' ratio (w/w) of 6. XRD spectrum confirmed the presence of silver nanocrystallites on the prepared catalyst and TEM images their sizes mostly lower than 150 nm.The Ag/C catalyst prepared in a mildly basic solution (pH 9) showed higher catalytic activity, as well as higher reusability, compared to that prepared in a mildly acidic solution (pH 5-7).