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A simple and efficient microwave-assisted procedure for synthesis of L-cysteine-capped nickel nanoparticles(cyst-Ni NPs) in ethylene glycol solvent was demonstrated. The as-synthesised NPs were characterised by ultraviolet–visible(UV–Vis) spectrophotometer, Fourier transform infrared(FTIR) spectroscopy, transmission electron microscopy(TEM) and X-ray diffractometry(XRD). The cyst-Ni NPs are proved to be excellent heterogeneous catalysts for the 100% reduction of 4-nitrophenol(4-NPh) in the presence of reductant(Na BH4)within reaction time of 40 s. In contrast, Raney nickel in similar sample environments shows only 25.5% reduction.The kinetic and energetic behaviours of cyst-Ni NPs were also studied, and the reduction reaction is determined to follow pseudo-first-order kinetics with a rate constant value of 0.115 s-1 and activation energy of 36.1 kJ·mol-1. In addition to its high catalytic competence, cyst-Ni NPs catalyst exhibits excellent recyclability with negligible catalytic poisoning.
A simple and efficient microwave-assisted procedure for synthesis of L-cysteine-capped nickel nanoparticles (cyst-Ni NPs) in ethylene glycol solvent was demonstrated. The as-synthesizeded NPs were characterised by ultraviolet-visible (UV- Transmission electron microscopy (TEM) and X-ray diffractometry (XRD). The cyst-Ni NPs are proved to be excellent heterogeneous catalysts for the 100% reduction of 4-nitrophenol (4-NPh) in the Presence of reductant (Na BH4) within the reaction time of 40 s. In contrast, Raney nickel in similar sample environments shows only 25.5% reduction. kinetic and energetic behaviors of cyst-Ni NPs were also studied, and the reduction reaction is determined to follow pseudo-first-order kinetics with a rate constant of 0.115 s-1 and activation energy of 36.1 kJ · mol- 1. In addition to its high catalytic competence, cyst-Ni NPs catalyst exhibits excellent recyclability with negligible catalytic p oisoning