title: Biosynthesised palladium nanoparticles using Eucommia ulmoides bark aqueous extract and their catalytic activity.
abstract: Palladium nanoparticles (PdNPs) are of great importance as catalytic materials. Their synthesis has been widely studied and interest in their properties is growing. Bio-based methods might be a greener option for designing the PdNPs with reduced environmental impacts. This study reports the synthesis of PdNPs by utilising the aqueous extract of medicinally important Eucommia ulmoides (E. Ulmoides) bark which functions as both reducing and capping agent in moderate reaction conditions. Reduction potential of E. Ulmoides bark aqueous extract was about -0.08 V vs. saturated calomel electrode by open-circuit voltage method and the rich polyphenolics was confirmed by cyclic voltammetry, which helps to reduce palladium ions to PdNPs. The characterisation through high-resolution transmission electron microscopic, energy dispersive X-ray spectroscopy and X-ray diffraction infer that the as-synthesised PdNPs were spherical in shape with a face cubic crystal structure. The results from dynamic light scattering suggest the PdNPs have the narrow size distribution with an average size of 12.6 nm. The lower zeta potential (-25.3 mV) and the Fourier transform infrared spectra indicate that the as-synthesised PdNPs keep remarkably stable for a long period due to the capped biomolecules on the nanoparticle surface. This method for synthesis of PdNPs is simple, economic, non-toxic and efficient. The PdNPs show excellent catalytic activity for the electro-catalytic oxidation of hydrazine and the catalytic reducing degradation of p-aminoazobenzene, a model compound of azo-dyes.
authors.affiliation: College of Chemistry and Biology, Hubei University of Education, Wuhan 430205, People's Republic of China.
authors.forename: Liansheng
authors.initials: L
authors.lastname: Duan
authors.affiliation: College of Chemistry and Chemical Engineering, Wuhan Textile University, Wuhan 430073, People's Republic of China.
authors.forename: Ming
authors.initials: M
authors.lastname: Li
authors.affiliation: Hubei Key Laboratory of Low Dimensional Optoelectronic Material and Devices, Hubei University of Arts and Sciences, Xiangyang, Hubei 440053, People's Republic of China. huihongliu@wtu.edu.cn.
authors.forename: Huihong
authors.initials: H
authors.lastname: Liu
mesh_terms: D001688:Biological Products / Q000138:chemical synthesis*; D002384:Catalysis; D031283:Eucommiaceae / Q000737:chemistry*; D055772:Green Chemistry Technology / Q000379:methods; D008422:Materials Testing; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D010165:Palladium / Q000737:chemistry / Q000302:isolation & purification*; D010316:Particle Size; D024301:Plant Bark / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry*; D014867:Water / Q000737:chemistry
chemical_list: D001688:Biological Products; D010936:Plant Extracts; D014867:Water; D010165:Palladium