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Room Temperature Synthesis of Ferroelectric Barium Titanate Nanoparticles Using Peptide Nanorings as Templates

“…The electron diffraction pattern of the resulting BaTiO 3 nanoparticles in the inset of Figure 3 resolves the characteristic (002) and (200) faces of the tetragonal BaTiO 3 crystals. [30] To test the nanometerscale ferroelectric property of the tetragonal BaTiO 3 nanoparticles, electrostatic force microscopy (EFM) was used to image and manipulate the ferroelectric polarization of these nanoparticles. This procedure is summarized in Figure 4a.…”

Electrical and structural characterization of PTCR pure BaTiO3 nanopowders synthesized by sol–gel emulsion technique

“…DSC is known to be very sensitive to the phase change, and shows an endothermic peak at the tetragonal to cubic transition temperature of BaTiO 3 [17,37]. As reported by Takeuchi et al [17] the particle size increased with increasing sintering temperature, which in turn increased the tetragonality in the crystals. For powders showing tetragonality below 60% no such endothermic peak was observed and only at 64% a weak diffused peak was achieved.…”

“…For powders showing tetragonality below 60% no such endothermic peak was observed and only at 64% a weak diffused peak was achieved. However, above 80% tetragonality a very distinct endothermic peak was obtained, with a transition enthalpy (ΔH) value of 200 J/mol for 95% tetragonality [17]. Xu et al also reported the DSC peak for particles with a minimum of 80% tetragonality having ΔH value of 0.7-0.75 J/g [38].…”

“…Highpermittivity and stable dielectric constant for a large temperature range is required of a BaTiO 3 ceramic capacitor [41]. Hence a better control of the dielectric constant in the form of diffused transition is desired which can be achieved if the tetragonality is precisely controlled, and to do so, dopants are added so as to chemically modify the BaTiO 3 [17,40,41]. heat treated at 400°C, 500°C, 600°C, 700°C, 800°C, 900°C, and 1000°C.…”

“…Of these, the commercially used solid state method produces particles in the micro-meter range with presence of BaCO 3 even after calcinations at temperatures as high as 1400°C for several hours. Ferroelectric properties are highly dependent on the grain size, domain structure, and composition due to which control of processing conditions including thermal treatment are required [14,17,18]. Hence, wet chemical methods like sol-gel have been studied to generate highly pure, homogeneous, reactive ultrafine barium titanate powders [15,16,19].…”