A novel two-phase composite film is prepared by the solvent casting method employing poly（methyl methacrylate） （PMMA） as polymer matrix and bismuth ferrite （BFO） as ceramic filler. The surfaces of BFO are functi...A novel two-phase composite film is prepared by the solvent casting method employing poly（methyl methacrylate） （PMMA） as polymer matrix and bismuth ferrite （BFO） as ceramic filler. The surfaces of BFO are functionalized by proper hydroxylating agents to activate their chemical nature. The structural analysis of the composite films confirms that the composites made up of functionalized BFO （BFO-OH） have a distorted rhombohedral structure. The morphological analysis shows that BFO- OH particles are equally distributed over the polymer matrix. The -OH functionality of BFO-OH is confirmed by FTIR. The dielectric and electrical studies at a frequency range from 100 Hz to I MHz reveal that PMMA-（BFO-OH） composites have enhanced dielectric constant as well as electrical conductivities, much higher than that of unmodified composites. According to the ferroelectric measurement result, the hydroxylated composite film shows a superior ferroelectric behavior than that of the unmodified one, with a remanent polarization （2Pr） of 2.764μC/cm2,展开更多
The surface hydroxylation treatment has been carried out by using hydrogen peroxide(H_(2)O_(2))to modify the surface of Na_(0.5)Bi_(0.5)TiO_(3)(NBT)particles in a ferroelectric polymer(PVDF)via solution casting techni...The surface hydroxylation treatment has been carried out by using hydrogen peroxide(H_(2)O_(2))to modify the surface of Na_(0.5)Bi_(0.5)TiO_(3)(NBT)particles in a ferroelectric polymer(PVDF)via solution casting technique.The FTIR study confirms the presence of hydroxyl groups on the surface of NBT.The FE-SEM analysis reveals that h-NBT particles are dispersed homogeneously within the polymer matrix.The surface hydroxylation treatment plays an important role in high dielectric constant and also reduced loss by conducting the material surface withOH functional groups.The prepared composite with 40 wt.%of h-NBT showed enhanced dielectric constant(≈114),negligible loss(0.22)and high AC conductivity as compared to that of the unmodified NBT.Such significant enhancement in dielectric properties may be due to the strong interaction between h-NBT particles and PVDF matrix at the interface.The percolation theory is used to explain the dielectric properties of h-NBT-PVDF composite.Furthermore,the remnant polarization of the un-poled h-NBT-PVDF composites(2 Pr–1.19C/cm^(2) for 40 wt.%of h-NBT)is also improved.The present findings give an idea of high dielectric constant and relatively low loss composite materials as a promising candidate for electronic and energy storage devices.展开更多
文摘A novel two-phase composite film is prepared by the solvent casting method employing poly（methyl methacrylate） （PMMA） as polymer matrix and bismuth ferrite （BFO） as ceramic filler. The surfaces of BFO are functionalized by proper hydroxylating agents to activate their chemical nature. The structural analysis of the composite films confirms that the composites made up of functionalized BFO （BFO-OH） have a distorted rhombohedral structure. The morphological analysis shows that BFO- OH particles are equally distributed over the polymer matrix. The -OH functionality of BFO-OH is confirmed by FTIR. The dielectric and electrical studies at a frequency range from 100 Hz to I MHz reveal that PMMA-（BFO-OH） composites have enhanced dielectric constant as well as electrical conductivities, much higher than that of unmodified composites. According to the ferroelectric measurement result, the hydroxylated composite film shows a superior ferroelectric behavior than that of the unmodified one, with a remanent polarization （2Pr） of 2.764μC/cm2,
基金The authors gratefully acknowledge the financial support obtained from the DST-FIST and UGC-DRS grant for the development of research work in the School of Chemistry,Sambalpur University,UGC-MRP under the grant head F.No.42–277/2013(SR),New Delhi,India,and also the project grant of DST Govt.of Odisha,India.We also thank UGC,New Delhi for financial support through the BSR Research fellowship.
文摘The surface hydroxylation treatment has been carried out by using hydrogen peroxide(H_(2)O_(2))to modify the surface of Na_(0.5)Bi_(0.5)TiO_(3)(NBT)particles in a ferroelectric polymer(PVDF)via solution casting technique.The FTIR study confirms the presence of hydroxyl groups on the surface of NBT.The FE-SEM analysis reveals that h-NBT particles are dispersed homogeneously within the polymer matrix.The surface hydroxylation treatment plays an important role in high dielectric constant and also reduced loss by conducting the material surface withOH functional groups.The prepared composite with 40 wt.%of h-NBT showed enhanced dielectric constant(≈114),negligible loss(0.22)and high AC conductivity as compared to that of the unmodified NBT.Such significant enhancement in dielectric properties may be due to the strong interaction between h-NBT particles and PVDF matrix at the interface.The percolation theory is used to explain the dielectric properties of h-NBT-PVDF composite.Furthermore,the remnant polarization of the un-poled h-NBT-PVDF composites(2 Pr–1.19C/cm^(2) for 40 wt.%of h-NBT)is also improved.The present findings give an idea of high dielectric constant and relatively low loss composite materials as a promising candidate for electronic and energy storage devices.
