The Effects of Reducing Agents on Particle Size and Distribution of Prepared Gold Nanoparticles

The effects of different reductants( hydroxylamine hydrochloride,sodium borohydride) on shape,average size and size distribution of gold nanoparticles( GNPs) were investigated. The prepared GNPs were characterized by UV-vis and TEM. The catalytic activities of GNPs were evaluated in the reduction of p-nitrophenol to p-aminophenol. By TEM characterization,the prepared GNPs were almost spherical,and the GNPs prepared by the combination usage of hydroxylamine hydrochloride followed by sodium borohydride in sequence as reducing agents were with minimal size of 4. 0 nm in mean diameter and with better size distribution,and therefore showed the best catalytic performance and high TOF in the reduction of p-nitrophenol into p-aminophenol. Meanwhile,sodium borohydride not only provided an alkaline condition for hydroxylamine hydrochloride,but also acted as an important reducing agent.