Microstructural Analysis On The Doped Bi-superconductor

In this article,a high temperature superconductor of Ni-doped Bi2Sr2CaCu2O8+δsystem were studied.we studied schematically on the phase composition of the products,crystal structure and lattice constant of the main phase,morphology,particle size,distribution and orientation of secondary-phase particles.Our analytic instruments conclude:XRD(X-ray Diffraction),SEM(Scanning Electron Microscope),TEM(Transmission Electron Microscope),EDS(Energy Dispersive Spectrometer),and so on.The results showed the following conclusion:Under the suitable conditions of the synthesis of Bi-2212 powder,the Bi-2212 lattice parameter a b and c calculated by XRD had no obvious change,while the EDS energy spectrum showed that the Bi-2212 phase did not contain Ni elements.It could be found that the Ni element did not change the lattice parameter of Bi-2212,and it did not entere into the lattice structure of Bi-2212.Ni existed in the second phase of NiO and the particle size of NiO rangeed from 20 to 500 nm.NiO particles in size of 20-100 nm appeared a the amorphous form;NiO particles in size of 100-300 nm appeared nearly spherical shape,NiO particles more than 300 nm appeared near a square shape.In particular,the size of nm NiO 1-100 particles could become strong pinning centers.By selected area electron diffraction patterns and high resolution images of the combination of NiO and Bi-2212,we could see that:crystal zone axis[01 (?)]NiO//[60 (?)]Bi-2212,(111)NiO//(126)Bi-2212 and their misfit is 9.415%;(200)NiO//(2 0 12)Bi-2212 and their mismatch is 11.039%.They are half a coherent matching.Crystal zone axis[0 1 (?)]NiO//[6 0 (?)]Bi-2212,(111)NiO//(126)Bi-2212 and their misfit is 9.415%;(200)NiO//(2 0 12)Bi-2212 and their mismatch is 11.039%.They are half a coherent matching.[001]NiO//[15 (?) ]Bi-2212,(200)NiO//(2 0 10)Bi-2212 and their mismatch is 2.9%.They are a coherent matching.