Fabrication Of Nanoporous Cobalt And Its Catalytic Degradation Of Azo Dyes

Nanoporous metals with the properties of high porosity and large specific surface area of porous materials,and the charactics of high conductivity,high thermal conductivity,corrosion resistance and fatigue resistance of metal materials,have attracted much attention of the reserachers,in this reserach,the Nanoporous Co is fabricated by the electrochemical dealloying with amorphous alloy as precursors and the microstructure is adjusted.The mian results is listed as following,(1)The ribbon samples of Zr56Al16Co28,Zr56Al16-xCo28Agx(x=1,3 at%)and Zr56Al16-xCo28Nix(x= 1,3 at%)are prepared using arc smelting and melt-spinning.X ray diffraction(XRD)and differential scanning calorimetry(DSC)are used to characterize the structure and to analyse the thermal stability.The results show that the ribbon samples are in amorphous state,and the addition of low surface diffusion elements have influences on the thermal stability of Zr-Al-Co amorphous alloy.(2)Nanoporous Co is prepared by electrochemical dealloying in 0.5 wt%NH4F and 1 M(NH4)2SO4 solution.Nanoporous structures with the mean pore size of 44.7 nm are formed after dealloying in F-containing solution.(3)Both the addition of low surface diffusion elements(Ag or Ni)in Zr-Al-Co amorphous alloy,and the addition of 0.1 g/L PVP organic macromolecules in dealloying solution are effective to refine the pore size of nanoporous Co.The mechanism of refinement is discussed in this paper.(4)The nanoporous Co,Zr56Al16Co28 amorphous alloy and the nanoporous Co with Ag are used as electrodes to catalysis degrade Direct blue 6 and acid orange ? solution by electrochemical method.Results show that the nanoporous Co exihibit excellent catalysis degradation efficiency for direct blue 6 and acid orange ? solutions.The existence of Ag in the nanoporous structure further improves the degradation performance.The degradation mechanism is also discussed.