Location of Repository

Magnetic and electric properties of bismuth ferrite lead\ud titanate ceramics

By Timothy James Stevenson

Abstract

Solid solutions of multiferroic BiFeO3 doped with ferroelectric PbTiO3 (BFPT) can be prepared by conventional mixed oxide processing to produce a range of polycrystalline ceramics ranging throughout the xBiFeO3 - (1-x)PbTiO3 series. Sintered ceramics are shown to exhibit mixed tetragonal (P4mm) and rhombohedral (R3c) phase perovskite distortions from 0.4 ≤ x < 0.75, where at x ~\ud 0.75 a morphotropic phase boundary exists and compositions x > 0.75 are entirely rhombohedral.\ud \ud From extensive use of neutron diffraction experiments, the phase coexistence is attributed to compensation for the internal strain induced upon cooling through the ferroelectric Curie point from cubic, to the distorted tetragonal perovskite phase (ܿ/ܽ = 1.17). This drives a further partial transformation to the (~4 %) lower volume\ud rhombohedral phase as a relief mechanism. \ud \ud Increasing the sinter temperature and fast cooling (> 900 °C/hr) sees the monolithic samples x ≤ 0.7 disintegrate to various levels of particulate size, when a critical\ud grain size is exceeded (7 μm), which in turn is inversely proportional to the grain boundary fracture energy. The magnetic properties studied using high resolution\ud powder diffractometry of these two states present G-type antiferromagnetism (AFM) in both the rhombohedral and tetragonal phases; but with Tn above ambient temperature for R3c, and below for P4mm for all compositions except x = 0.3. Compositions below this PbTiO3 rich solution are never observed to support antiferromagnetic order, as the dilution of magnetic iron ions exceeds the percolation threshold via substitution with titanium ions.\ud \ud The rhombohedral phase is shown to exhibit an incommensurate, modulated magnetic order, with a propagation vector perpendicular to the magnetization\ud vector, which decreases in periodicity with increasing bismuth ferrite, from 840 Å for x = 0.75. At room temperature, transforming the paramagnetic tetragonally distorted powder to a G-type AFM rhombohedral phase, is observed with the application of hydrostatic pressure. Evident from neutron experiments, using the Pearl instrument\ud at ISIS, full transformation can be achieved with moderate pressures of 0.77 GPa, effectively ‘switching’ on the magnetic order.\ud \ud The monolithic samples were used at 250 K to observe the changes in simultaneous structural and G-type antiferromagnetic properties as a function of applied electric field (0 to 10 MVm-1) for the most piezoelectrically active samples, around the MPB composition (x = 0.7), using neutron diffraction at the Berlin neutron scattering centre; instrument E2.\ud \ud An observed increase in rhombohedral phase occurs with the application of electric field from peak analysis, which relates to a proportional increase in observed antiferromagnetic intensity (5 %).\ud \ud These two behaviours are proposed to be linked by the internal strain developed within the system, from increased polarisation forcing a partial phase transformation\ud from the tetragonal to the rhombohedral phase which can support the antiferromagnetic order at room temperature

Publisher: Institute for Materials Research (Leeds)
Year: 2010
OAI identifier: oai:etheses.whiterose.ac.uk:1371

Suggested articles

Preview

Citations

  1. (1994). A correction for powder diffraction peak asymmetry due to axial divergence.”
  2. (1865). A Dynamical Theory of the Electromagnetic Field.”
  3. (1952). A monoclinic ferroelectric phase in the Pb(Zr1-xTix)O3 solid solution.”
  4. (1973). A note on the derivation of Heesch groups.” Acta Cryst.
  5. (2005). A.,(2005) “Weak ferromagnetism and magnetoelectric coupling in bismuth ferrite.”
  6. (2009). About Us” and “Technology”. [online] [Accessed: 26 th
  7. (1956). Acta Crystallography.
  8. (1958). Addison-Wesley (translation of Russian ed.
  9. (1960). Anisotropic superexchange interaction and weak ferromagnetism.”
  10. (1963). Antiferromagnetic properties of some perovskites.”
  11. (1933). Atomic moments in ferromagnetic metals and alloys with nonferromagnetic elements.”
  12. (1946). Barium Titanate - a new ferro-electric’,
  13. (1974). Capture of slow neutrons.”
  14. (2010). Change in periodicity of the incommensurate magnetic order towards commensurate order in bismuth ferrite lead titanate.”
  15. (2003). Chapter in “Introduction to complex mediums for optics and electromagnets.”
  16. (1958). Choice of collimators for a crystal spectrometer for neutron diffraction.”
  17. (2007). Condensed Matter,
  18. (2003). Core Technology.” [online] [Accessed 15 th July,
  19. Cross (2003)(c)
  20. (2002). Crystal structure and spiral magnetic ordering of BiFeO3 doped with manganese.”
  21. (1945). Crystal Structure Of Barium Titanate’,
  22. (1600). De Magnete” Volume 1893. Part 1. Dover Publications. Translated
  23. (2002). Density functional studies of multiferroic magnetoelectrics.”Annu.
  24. (2004). Development of the high-temperature phase of hexagonal manganites.”
  25. (2005). Dictionary of microscopy.” Wiley.
  26. (1926). Die gesetze der krystallochemie”
  27. (1994). Dielectric behaviour and magnetoelectric effect in cobalt ferrite-barium titanate composites.”
  28. (1945). Dielectric constants of some titanates.”
  29. (1995). Early development of neutron scattering.”
  30. (1966). Effect of grain size on microcracking in lead titanate ceramics.”
  31. (1965). Effects of strain induced by pressing and grinding
  32. (2007). Electrical characterization of magnetoelectrical materials.”
  33. (2008). Electricfield induced spin flop in BiFeO3 single crystals at room temperature.”
  34. (2003). Electroceramics: Materials, Properties, Applications.” nd Edition.
  35. (1960). Electrodynamics of continuous media.”
  36. (2001). Electron microscopy and analysis.” Taylor and Francis.
  37. (2007). Electronic structure and magnetism of EuTiO3: a first-principles study”
  38. (1993). et al (1994)(c)
  39. (1931). et al.(1980) “Temperature dependence of the crystal and magnetic structures of
  40. (1820). Experimenta Circa Effectum Conflictus Electrici in Acum Magneticam”,
  41. (2006). Factors influencing the piezoelectric behaviour of PZT and other “morphtotropic phase boundary” ferroelectrics.”
  42. (2007). Ferroelastics.” Presentation given
  43. (1993). Ferroelectric crystals.”
  44. (1953). Ferroelectricity versus Antiferroelectricity in the solid solutions of PbZrO3 and
  45. (1957). Ferroelectrics &
  46. (2000). First principles study of multiferroic magnetoelectric
  47. (1963). Forrat
  48. (2008). Growth and characterisation of bismuth ferrite lead titanate single crystals.” Thesis. Conducted in the Institute for Materials Research at the University of Leeds.
  49. (2010). High Temperature Phase Transitions in
  50. (2007). Internal Stress and Phase Coexistence in…”
  51. (1995). International tables for crystallography.” Mathematical, Physical and Chemical Tables,
  52. (1992). Introduction to Crystallography” Revised Edition.
  53. (2000). Introduction to ferroic materials.”
  54. (1972). Introduction to magnetic materials.”
  55. (1978). Introduction to the Theory of Thermal Neutron Scattering”
  56. (1995). Investigation of tetragonal distortion in the PbTiO3-BiFeO3 system by high-temperature x-ray diffraction.”
  57. (2010). ISIS – Pearl high pressure powder diffractometer.” [online]
  58. (1985). Léon Nicolas Brillouin – A biographical memoir.” National Academy of Sciences.
  59. (1927). Les moments de rotation et le magnétisme dans la mécanique ondulatoire (translated; the rotary moment and magnetism in wave mechanics)”
  60. (1994). Magnetic and crystallographic order in α-manganese.”
  61. (1994). Magnetic ferroelectric materials.”
  62. (2001). Magnetism in condensed matter.”
  63. (2006). Magnetocapacitance without magnetoelectric coupling.”
  64. (2003). Magnetocapcitance effect in multiferroic
  65. (2001). Magnetoelectric effect in composites of magnetorestrictive and piezoelectric materials.”
  66. (1994). Magnetoelectric interaction phenomena
  67. (2004). Magnetoelectric Interaction Phenomena in Crystals.”
  68. (1994). Magnetoelectric properties of some rare earth molybdates.” Ferroelectrics.
  69. (1999). Magnetoelectronics applications.”
  70. (2008). Materials Chemistry and Physics.
  71. (2000). Materials Science and Engineering An Introduction.” Fifth Edition.
  72. (2004). Measurement and characterisation of magnetic materials.” Italy.
  73. (2008). Mulitferroics and magnetoelectrics: thin films and nanostructures.”
  74. (2006). Multiferroic and magnetoelectric materials.”
  75. (1970). Multiferroics: progress and prospects in thin films.”
  76. (1955). Neutron diffraction study of the magnetic properties of the series of perovskite-type compounds [(1-x)La, xCa]MnO3” Physical Review.
  77. (1992). Neutron scattering lengths and cross sections.”
  78. (2006). Neutron Training Course” Book and Presentations Edited by
  79. (2006). Neutron Training Course” Book and Presentations from the ISIS Neutron Training Course held at Rutherford Appleton Laboratories,
  80. (1913). On the Constitution of Atoms and
  81. (2008). Origin of morphotropic phase boundaries in ferroelectrics.”
  82. (1979). Physical properties of Crystals: Their representation by Tensors and Matrices”
  83. (2009). Physics and applications of
  84. (1971). Piezoelectric Ceramics.”
  85. (1954). Piezoelectric properties of Lead Zirconate-Lead Titanate Solid-Solution Ceramics.”
  86. (1970). Possible species of Ferromagnetic, Ferroelectric,
  87. (2008). Preparation and properties of bismuth ferrite-lead titanate thin films prepared by pulsed laser deposition.”
  88. (2002). Pressure and Temperature Dependence of the Ferroelectric-Paraelectric Phase Transition in
  89. (2003). Recent advances and future directions in magnetic materials.”
  90. (1993). Recent advances in magnetic structure determination by neutron powder diffraction.”
  91. (2005). Review of crystal and domain structures in the PbZrxTi1-xO3 solid solution.
  92. (2005). Revival of the magnetoelectric effect.”
  93. (1999). Rietveld refinement guidelines.”
  94. (2003). Scanning electron microscopy and X-ray microanalysis.” 3 rd ed.
  95. (2008). Schéma de principe du synchrotron.” [online] [accessed 26 th July,
  96. (2002). Solid State Comms.
  97. (1966). Some of the properties of ferromagnetoelectric
  98. (1964). Soviet Physics-
  99. (1990). Structure of a ferroelectric and ferroelastic monodomain crystal…”
  100. (1960). Structure of the new antiferromagnetic BiFeO3.” Sov.
  101. (1997). Sun et al
  102. (1894). Sur la symétrie des phénomènes physiques: symétrie d'un champ électrique et d'un champ magnétique.”
  103. (1967). Tables of the Brillouin function and of the related function for the spontaneous magnetization.”
  104. (1969). The atomic structure of
  105. (1997). The basics of crystallography and diffraction.” International Union of Crystallography.
  106. (1972). The Classification of Tilted Octahedra
  107. (1925). The configuration of polyatomic polar molecules I.” Zeitschrift Fur Physik.
  108. (1970). The electrodynamics of magneto-electric media.”
  109. (2008). The interplay of magnetism and structure in patterned multilayer thin films.” Thesis (Ph.D). Physics and Astronomy,
  110. (1966). The nature of the dielectric and magnetic properties of
  111. (1965). The physical principles of magnetism.”
  112. (1977). The structures and properties of solids” 6 th Ed.
  113. (2004). Time resolved neutron studies of metallic phase formation.” Thesis (PhD).
  114. (1997). User guide for the Polaris powder diffractometer at ISIS.”
  115. (1997). Very High Resolution Diffractometry at Pulsed Neutron Sources.”
  116. (1953). X-ray line broadening from filed aluminium and wolfram.”
  117. (1950). X-ray study of the phase transition in lead titanate.”

To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.