2. Effect of HSMF on Electrodeposited Ni-Fe Membrane-- Crystal Morphology and Magnetism Performance Yunbo Zhong, Yanling Wen, Zhongming Ren, Kang Deng, Kuangdi Xu Shanghai Key Laboratory of Modern Metallurgy & Material Processing, Shanghai University 2nd Sino-German Workshop on EPM, October, 16-19, 2005, Dresden, Germany

3. Outline Motivation; Experimental Apparatus; Results and Discussion; Conclusion and Outlook; Acknowledgement;

4. Influence on electron transfer kinetics ? Influence on mass transport MHD effect  Influence on Surface Diffusion 、 Necleation 、 Crystal Growth ? 1.Motivation Electro-Crystallization in HSMF H2OH2O Me 2+ Metal Membrane E0E0 Charge Transfer Surface Diffusion Nucleation Crystal Growth Bulk Solution Boundary Layer

5. Variation of Free Energy in the process of Electro-deposition of NiFe membrane The χ data is very lacking, and the magnetism of ions in solution are not very clear Ni 2+ : Paramagnetism ; Fe 2+ : Diamagnetism; Ni atom: Paramagnetism; Fe atom: Paramagnetism; Ni Crystal: Ferromagnetism; Fe Crystal: Ferromagnetism;

6. PID Temperature Controller B I B⊥IB⊥I B I B//I Magnetic Field Center Nitrogen Thermocouple Water-cooling Pipe Supercon- ductive Coil Heater Electrolyte Heat Insulator Quartz Pipe Electrode B + - Fix Block 2.Experimental Equipment Nickel Plate Copper Foil

7. Distribution of MFD in High Static Magnetic Field Homogeneous MFUpper Gradient MF Lower Gradient MF

8. Effect of HSMF on electrodeposited Ni-Fe membrane When I ⊥ B B I Magnetic Field Center Ni 2+ : 1.2mol/l; Fe 2+ : 0.07mol/l pH=3.5; J=4.0A/dm 2 3.Results and Discussion

9. Surface SEM pictures of NiFe membrane electrodeposited in various magnetic fields(J=4A/dm 2 ) 0T 4T6T8T10T12T

10. Across-section SEM pictures of NiFe membrane electrodeposited in various magnetic fields(J=4A/dm 2 ) ( -electrodeposit growth direction ) 0T 4T6T 8T12T10T B

11. XRD patterns of the NiFe membranes electrodeposited in different magnetic flux density Intensity ratio of three main peaks: I (111) :I (200) :I (220) = ( 0T) 100:54.3:4.3 ; (04T) 100:24.7:6.2 ; (06T) 100:26.9:6.4 ; (08T) 100:28.8:7.1 ; (10T) 100:28.2:8.4 ; (12T) 100:19.1:6.6 (111) (200) (220) (111) (200) (220)

12. M － Crystal orientation coefficient ； I(hkl) － Measured value of the (hkl) plane diffraction peaks ； I 0 (hkl) － Standard value of the (hkl) plane diffraction peaks in PDF card ； Crystal Orientation Discussion

13. Effect of MFD on Crystal Orientation Coefficient

14. EDS analysis of the samples electrodeposited in different magnetic fields (Fe wt%= 0T- 12.71 %; 6T- 14.99 %; 10T- 23.32 %; 12T- 26.10 %.) 0T 6T 10T12T

15. The relation between saturation magnetization of the samples and preparation magnetic flux density

16. Effect of magnetic field on electrodeposited Ni-Fe membrane When B//I B I B//I Magnetic Field Center

17. SEM pictures of the surface of NiFe membrane electrodeposited in parallel magnetic fields(J=4A/dm 2 ) 0T4T6T 8T10T12T

18. 6T 0T SEM pictures of the across-section of NiFe membrane electrodeposited in parallel magnetic fields (J=4A/dm 2 ) 10T 12T 4T 8T B J

19. XRD patterns of the NiFe membranes electrodeposited in different static magnetic fields (Strength ratio of three main peaks ： I(111):I(200):I(220)= (0T) 100:41.1:4.5 ; (6T) 100:25.8:6.6 ; (10T) 100:27.2:7.6 ; (12T) 100:26.1:7.4 )

20. Analysis of crystal orientation coefficient of the samples

21. EDS analysis of the samples electrodeposited in different magnetic fields (Fe wt%= 0T- 14.13 %; 6T- 14.12 %; 10T- 15.17 %; 12T- 14.47 %.) 0T 6T 10T12T

22. The relation between saturation magnetization intensity of the samples and preparation magnetic field

23. Effect of magnetic field on electrodeposited Ni- Fe membrane When B//I Without Bubble Agitation and at Room Temperature B I B//I Magnetic Field Center

24. 0T 10T

25. Electro-depostion of NiFe Membrane in Gradient Magnetic Field (B//I) +400T 2 /m 0-400T 2 /m J=0.3A/cm 2 Room Temperature, No Agitation

26. Magnetic Field Gradient ElementWt %At% +400T 2 /m FeK 38.37 39.56 NiK61.6360.44 0T 2 /m FeK 22.84 23.73 NiK77.1676.27 +400T 2 /m FeK 29.39 30.44 NiK70.6169.56

27. (a) 0T(b) B 1 (B 1 ≠0T)B 2 (B 2 ≥10T) Hydration Ions Metal atom Metal Crystal Sphere Crystal nucleus FLFL I B FEFE Outer Helmholtz area Bulk solution Trajectory of Ions Boundary Layer Trajectory of Ions Sketch Map of Nucleation and Crystal Growth when B ⊥ I In Homogeneous Magnetic Field Discussion

28. Initial velocity (v 0 ) Bubble Direction of electric field (I) Direction of magnetic field (B) Cathode Anode Sketch Map of Nucleation and and Crystal Growth when B//I In Homogeneous Magnetic Field Magnetic field Migration of atoms in Horizontal direction

29. B I B//I B J Sketch Map of Nucleation and and Crystal Growth when B//I and in Gradient Magnetic Field Room Temperature, No Agitation

30. Interpret for the Composition-Change of Electrodeposited Ni-Fe Membrane in HSMF B I B//I BdB/dz Fe 2+ Rich Stable area B I I B ⊥ J Agitation Homo. MF B//J Agitation Homo. MF B//J No Agitation Gradient MF z

31. 4.Elementary Conclusions In HSMF, Strengthened MHD effect can influence the crystal morphology of electrodeposited NiFe membrane remarkably, so do the mass transfer process; Both perpendicular and parallel magnetic field can make the crystal (111) plane orientation reinforced; The ion concentration in electrolyte would be changed due to different magnetism property of ions in gradient HSMF, which would effect the composition of deposit; The superimposition of HSMF would affect the nucleation of electro-crystallization process; The saturation magnetization of Ni-Fe membrane was determined mainly by the concentration of iron.

32. Outlook There are a lot of questions need to be made clear: Will HSMF change the electron transfer process? Simulation on the nucleation of crystal when electro- deposition in HSMF; The magnetic susceptibility (x) Value of ions in electrolyte; Can we control the structure even the property of membrane? ………… To answer those questions, maybe we can collaboration with Germany Part and Chinese Part!

33. 5.Acknowledgement This work was financial supported by Shanghai Scientific & Technological Committee (Key Project No. 03JC14029); Thankful to Sino-German Center for Research Promotion to Support this Workshop; Thankful to Dr. Gerbeth for well organization!

34. Thank you for your attentions!

35. Effect of magnetic field on electrodeposited Ni-Fe membrane When I ⊥ B B I Magnetic Field Center Ni 2+ : 1.2mol/l; Fe 2+ : 0.07mol/l pH=3.5; J=4.0A/dm 2

36. SEM pictures of the surface of NiFe membrane electrodeposited without magnetic field (J= a-1A/dm 2 ; b-2A/dm 2 ; c-3A/dm 2 ; d-4A/dm 2 ; e-6A/dm 2 ) ab c de

37. a b c d e FSEM pictures of the across-section of NiFe membrane electrodeposited without magnetic field (J= a-1A/dm 2 ; b-2A/dm 2 ; c-4A/dm 2 ; d-5A/dm 2 ; e-6A/dm 2 )

38. Fig.17-a SEM pictures of the surface of NiFe membrane electrodeposited in 10T static magnetic field (J= a-1A/dm 2 ; b-2A/dm 2 ; c-3A/dm 2 ; d-4A/dm 2 ; e-5A/dm 2 ; f-6A/dm 2 ) abc de f

39. ab c d SEM pictures of the across-section of NiFe membrane electrodeposited in 10T static magnetic field (J= a-2A/dm 2 ; b-3A/dm 2 ; c-4A/dm 2 ; d-6A/dm 2 )