Preparation And Characterization Of Amorphous Ni-P And Ni-Co-B Metal Microspheres

Cenosphere is a new type of particulate material which has been developed since 1950's. As a cheap and light weight material, it is widely used in the field of aviation, space flight, machine, chemical industry, electric insulation, military and so on. This is attributed to its advantages of nontoxicity, self-lubricating capacity, disperse and floating easily, low heat conductivity, electric insulation, sound-proof and excellent stability etc. Template synthesis is a widely accepted method for preparing micro or nanomaterials because of its ability to control the dimensions of nanotubes.Firstly, in order to find the optimum formula and plating conditions, the alloy-coatings of Ni-Co-B were prepared on iron samples by electroless plating. And then, the preparations of Ni-P and Ni-Co-B metal micro-spheres via electroless plating using cenospheres as templates were investigated in this paper. The process included the pretreatment of the templates, electroless plating and removing of the templates. The final products were characterized by Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectrometer (EDS) and X-ray powder Diffractometer (XRD). The results showed that different metal micro-spheres can be prepared by electroless plating using cenosphers as templates. In this method, it is convenient to control the dimension and the shape of the obtained products by using different templates and controlling electroless deposition time.The catalytic activity of different structure Ni-P and Ni-Co-B products were studied in this paper. The liquid-phase hydrogenation of nitrobenzene reaction system was used to test the catalytic activity. Under the same experimental condition, the order of the conversion rate of nitrobenzene were Ni-P metal hollowspheres > Raney-Ni > Ni-P/cenosphere; Ni-Co-B metal hollowspheres > Raney-Ni > Ni-Co-B/cenosphere. After utilized 5 times, all the catalysts had better catalytic activity and longer life-span. The experimental results revealed that all of the Ni-P and Ni-Co-B alloy catalysts exhibit high catalytic activity in the liquid-phase hydrogenation of nitrobenzene.The preparations of Ni-P/CNF and Ni-Co-B/CNF catalysts via electroless plating were also investigated in this paper. The Scanning Electron Microscopy (SEM) and X-ray powder Diffractometer (XRD) were used to character the final products. The liquid-phase hydrogenation of nitrobenzene reaction system was used to test the catalytic activity. Under the same experimental condition, the order of the conversion rate of nitrobenzene were Ni-P/CNFs > Raney-Ni > Ni-Co-B/CNFs. The results showed that the alloy Ni-P/CNFs and Ni-Co-B/CNFs also exhibit high catalytic activity in the liquid-phase hydrogenation of nitrobenzene.