One-step green synthesis of palladium nanoparticles using neem gum (Azadirachta Indica): characterization, reduction of Rhodamine 6G dye and free radical scavenging activity

Nano-sized Palladium particles, synthesized by microwave irradiation method using neem gum, is a novel, single step and cost-effective with high yield. Water-soluble neem gum has been employed as stabilizing and reducing agent without any harmful chemicals for obtaining the PdNPs. The prepared PdNPs were characterized by UV-Vis, XRD, FTIR and TEM techniques. Average particle size was about 4 nm. FTIR confirmed that hydroxyl and carboxylic groups are involved in reduction and stabilizing process. The PdNPs catalytic activity was examined spectrophotometrically through the reduction of Rhodamine 6G dye by NaBH4. The PdNPs stabilized by neem gum exhibited excellent catalytic activity towards reduction of Rhodamine 6G. The reaction showed pseudo-first order kinetics and the rate constant obtained was 0.1875 min(-1). The antioxidant activity of PdNPs by DPPH was studied by UV-Visible spectrophotometry and PdNPs were found to have significant free radicle scavenging activity.