Peparation,Characterization And Properties Of Nano Nickel Catalyst

4-aminophenol(4-AP)is a vital intermediate for the manufacture of analgesic and antipyretic drugs,while 4-nitrophenol(4-NP)is a common organic pollution in the industrial and agricultural waste water.An efficient and environmentally friendly conversion route is the direct reduction of 4-NP to 4-AP.Many researchers pay attention to make this eco-friendly route come true.Various noble metals including Au,Ag and Pt nanocatalysts have been widely employed due to their efficient catalytic activities.However,they are too expensive which limit their industrial applications.An alternative way can be using transition metal catalysts to substitute noble metal catalysts,but there is a great challenge to improve the catalytic activities of the supported transition metal catalysts.In this work,we for the first time developed a novel in-situ calcination and reduction method to synthesize many kinds of supported Ni nanoparticles(NPs).We use SiO2 spheres or SiO2 nanotube as template to synthesize silicate precursors based on Kendal effect,followed by in-situ calcination and reduction method to fabricate Ni/SiO2@Au,Ni/SiO2 and Ni/SNTs nano composite.XRD,EDS and ICP were used to analysis structure and elements.SEM and TEM were used to analysis morphology and BET specific surface area was also studied.And finally,we studied the magnetic property and catalytic property of the as synthesized namomaterials.Because the high specific surface area,large loading capacity and ultra small Ni NPs size with good dispersion,the sample exhibits excellent catalytic performance in the 4-NP reduction compared to most supported Ni nanomaterials and many supported noble metal nanomaterials.In this thesis,Ni/SiO2@Au,Ni/SiO2 and Ni/SNTs nano composite were synthesized by an in situ decomposition and reduction of inorganic salt precursor and study the unique synthesized method in detail which solved the easy aggregation problem of small NPs.The NPs synthesized by this method have many advantages such as ultra-small NPs with good dispersion.Moreover,this is a eco-friendly method because organic solvent is not involved in.In particular,the synthetic strategy provides a useful idea for controlling synthesis other metal NPs supported materials with requisite loading capacity,which should be highly potential in diverse catalytic reactions.