Ultra-fine (PMN) powder synthesized from metal-citrate gel by thermal shock method

Progress in synthesis of ferroelectric ceramic materials via high-energy mechanochemical technique

“…Generally, they have a formula of Pb(B 0 B 00 )O 3 , where B 0 is a low-valence cation, such as Mg 2+ , Zn 2+ , Fe 3+ or Sc 3+ , and B 00 is a high-valence cation, such as Nb 5+ , Ta 5+ or W 6+ [116,119,130,132,134,141,142]. Relaxors are characterized by their high dielectric constant, broad and frequency-dispersive temperature dependence of dielectric constant.…”

“…columbite or Wolframite) are used to synthesize single phase or pyrochlore-free perovskite relaxors, via the conventional solid-state reaction process [114,115]. Many chemistrybased methods, such as co-precipitation, sol-gel, gel combustion and molten salt, have also been developed to produce phase-pure ultra-fine powders of relaxor ferroelectrics [116][117][118][119][120][121]. Comparatively, high-energy mechanochemical activation has been shown to be an alternative and effective process to prepare a wide range of phase-pure relaxor ferroelectric materials.…”

Microstructural and electrical study of mixed phase of Pb(Ba1/3Nb2/3)O3

“…Usual solid-state reaction route does not stabilize the perovskite phase in these materials [1]. A number of preparation routes are tried for these materials [2][3][4][5][6][7]; however, the two-stage columbite and B-oxide route lead to stable perovskite phase. Stabilizers are also used to increase the tolerance factor [8,9] and electro-negativity difference to get pure perovskite phase in some relaxors [10].…”

Effect of sintering conditions on the pyrochlore phase content in PMN–PFN ceramics prepared by sol–gel process

“…Ananta and Thomas 11 developed two-stage mixed oxide synthetic routes for the preparation of single phases of lead-based complex perovskite PMN and PFN and two complex perovskite compounds at selected compositions in the PMN-PFN pseudo-binary system were prepared and characterized 12 . PMN is also synthetized by various wet chemical processing routes such as sol-gel, 9,[13][14][15][16] combustion synthesis, 17,18 coprecipitation, 19 molten salt synthesis, 20 citrate gel, 21,22 partial oxalate, 23,24 polymerized complex, 24,25 citrate complex 26 and a niobium tartarate complex 27 methods. The combination of the partial oxalate method with the columbite route and the Pechini method was used to obtain PMN powder at low temperature.…”