Synthesis of Ni nanoparticles anchored on cellulose using different reducing agents and their applications towards reduction of 4-nitrophenol

Abstract

In this study, the immobilization of Ni nanoparticles on microcrystalline cellulose using hydrazine hydrate and sodium borohydride was investigated. The prepared Ni NPs/MCC1 and Ni NPs/MCC2 nanocomposites were then characterized using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), vibrating sample magnetometer (VSM) and inductively coupled plasma-optical emission spectroscopy (ICP-OES). The analyses exhibited that morphology of the Ni-nanocomposites and their magnetic characteristics were prominently depended to the applied reducing agents. This means that when hydrazine hydrate was used as a reducing agent, the formation of Ni NPs/MCC1 system with high crystallinity and magnetic characteristics was taken place. However, using sodium borohydride afforded the amorphous Ni NPs/MCC2 system with lowest magnetic property. At the next, catalytic activity of the prepared two nanostructured Ni-cellulose was investigated towards reduction of 4-nitrophenol to 4-aminophenol with the excess amounts of NaBH4 in water at room temperature. Both of the nanocomposites were easily separated from the reaction mixture using an external magnetic field or centrifugation. Reusability of two Ni-nanocomposites was studied for ten consecutive cycles without the significant loss of catalytic activity.