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Item type:Item, Effect of Na+ Substitution on the Phase, Microstructure, Electrical and Energy Storage Properties of BSBZNT Ceramics Prepared by the Solid-State Combustion Technique(2023-01-01) ;Chongsatan, Wistsarut ;Didpim, Ratirom ;Julphunthong, Phongthorn ;Thatawong, BhoowadolVittayakorn, Naratip(Ba<inf>0.704</inf>Sr<inf>0.176</inf>Bi<inf>0.12</inf>)<inf>1-x</inf>Zn<inf>0.08</inf>Nb<inf>0.04</inf>Ti<inf>0.88</inf>O<inf>3</inf>-Na<inf>x</inf> (BSBZNT-xNa) ceramics with x = 0, 0.01, 0.03 and 0.05 mol%, were prepared by the solid-state combustion technique. The samples were calcined and sintered at 950 °C and 1375 °C, respectively, for 2 h. The phase, microstructure, dielectric, ferroelectric and energy storage properties were investigated. The X-ray diffraction patterns of the BSBZNT-xNa powders showed a perovskite phase for all samples. When x increased from 0-0.03, the average particle size increased from 380 to 480 nm, then decreased to 420 nm. All sintered samples showed the coexistence of the orthorhombic and cubic phases. The average grain size was in the range of 2.03 to 1.39 µm. The BSBZNT-0.01Na ceramic exhibited the highest dielectric properties at room temperature (ɛ<inf>r</inf> = 902, tanδ = 0.10), the lowest remanent polarization (P <inf>r</inf> = 0.10 µC/cm<sup>2</sup>), coercive field (E <inf>c</inf> = 0.43 kV/cm), and the highest energy storage efficiency (η ∼ 94.70%) measured under an electric field of 70 kV/cm. - Some of the metrics are blocked by yourconsent settings
Item type:Item, BaTiO3/Epoxy Resin Nanocomposites as Flexible Energy Storage Devices(2023-01-01) ;Vittayakorn, Wanwilai ;Tepsansern, Piyapat ;Kriangkraikul, WorachetVittayakorn, NaratipIn this work, nanocomposites between the epoxy resin and barium titanate (BT) were prepared in order to use as flexible energy storage devices. The epoxy resin and BT phase were homogeneously mixed and cast into a disk shape. Phase formation and chemical properties of these nanocomposites were identified via XRD and FTIR methods, respectively. Frequency dependence of dielectric properties for all samples was measured by LCR meter. The polarization hysteresis loops were also investigated in order to calculate the energy density of materials. From the results, it was found that the dielectric constant and loss of these nanocomposites are independent of frequency and the ε<inf>r</inf> and tanδ values tend to increase with increasing BT amount. Moreover, after adding 50% of BT into the system, the energy density of nanocomposites is increased by five times compared with the pure epoxy resin while the energy loss density sharply decreases. The dielectric properties and the energy density of BT/epoxy resin nanocomposites change with BT content and strongly depend on porosity and the distribution of BT nanoparticles. - Some of the metrics are blocked by yourconsent settings
Item type:Item, Phase Formation, Morphology and Electrical Properties of Lead-Free BNBLT-xBSN Ceramics Synthesized via the Solid-State Combustion Technique(2023-01-01) ;Thatawong, Bhoowadol ;Vittayakorn, Naratip ;Rittidech, AurawanBongkarn, TheerachaiLead-free 1-x(Bi<inf>0.47</inf>Na<inf>0.47</inf>Ba<inf>0.06</inf>)<inf>0.95</inf>La<inf>0.05</inf>TiO<inf>3</inf>-xBa(Sn<inf>0.70</inf>Nb<inf>0.24</inf>)O<inf>3</inf> (BNBLT-xBSN) ceramics with x = 0, 0.01, 0.02, 0.03 and 0.04 mol.% were synthesized by the solid-state combustion technique with a calcination temperature of 750 °C for 2 h and a sintering temperature of 1150 °C for 2 h. The effect of BSN substitution on the phase formation, microstructure, dielectric, ferroelectric and energy storage properties of the BNBLT ceramics was investigated. With the substitution of BSN, the coexisting rhombohedral (R) and tetragonal (T) phases transformed into coexisting R and cubic (C) phase, verified by Rietveld refinement. The C phase increased with increased BSN content. The average grain size decreased from 1.14 to 0.89 µm when x increased to 0.03 and then increased to 0.96 µm. The measured density and maximum dielectric constant (ε <inf>m</inf>) tended to increase from 5.44 to 5.87 g/cm<sup>3</sup> and 1800 to 1942 when x increased to 0.03, then decreased to 5.25 g/cm<sup>3</sup> and 1501, respectively. The remanent polarization (P <inf>r</inf>) and coercive field (E <inf>c</inf>) decreased when x increased to 0.03. The 0.97BNBLT-0.03BSN ceramic exhibited the lowest energy loss density (W <inf>loss</inf> ∼ 0.10 J/cm<sup>3</sup>) and the highest energy-storage efficiency (η ∼ 77.3%) measured under an electric field of 70 kV/cm.
