The integration of ferroelectric materials as thin films has attracted considerable attention these last years thanks to their outstanding performances that allow considering new features for the realization of photov...The integration of ferroelectric materials as thin films has attracted considerable attention these last years thanks to their outstanding performances that allow considering new features for the realization of photovoltaic devices. Our study focuses on investigating structural, dielectric and ferroelectric properties of undoped and Mn doped PZN-4.5PT nanoparticles thin films on Silicon substrate. We fabricate very stable PZN-4.5PT nanoparticles thin films deposited on nanostructured silicon substrate with giant relative dielectric permittivity of 2.76 × 104 and 17.7 × 104 for respectively the undoped and Mn doped thin films. These values are very large compared to those found in single crystals and might be explained by the influence of the gel in which nanoparticles were dispersed. The SEM images show the crystallization of new hexagonal phases on the film surface probably coming from interaction between Si and the gel. The hysteresis loops permitted to determine the spontaneous polarization (Ps), remnant polarization (Pr) and coercive field Ec which are equal to 11.73 μC/cm2, 10.20 μC/cm2 and 20 V/cm, respectively for the undoped nanoparticles thin film and 22.22 μC/cm2, 19.32 μC/cm2 and 20 V/cm respectively for the Mn doped one. These values are high and correspond to the best ones found in literature compared to typical ferroelectric thin films.展开更多
This paper describes recent device developments with relaxor ferroelectric Pb(Zn_(1/3)Nb_(2/3))O_(3)-PbTiO_(3)(PZN–PT)single crystals carried out at Microfine Materials Technologies Pte.Ltd,Singapore.Promising[011]-p...This paper describes recent device developments with relaxor ferroelectric Pb(Zn_(1/3)Nb_(2/3))O_(3)-PbTiO_(3)(PZN–PT)single crystals carried out at Microfine Materials Technologies Pte.Ltd,Singapore.Promising[011]-poled transverse cuts of PZN–PT single crystals and the results on the effect of electric field and axial compressive stress on the rhombohedral-to-orthorhombic(R–O)phase transformation behavior of such cuts are presented and discussed.The single crystal devices described include a compact lowfrequency broadband power-efficient underwater tonpilz projector,high sensitivity shear accelerometers and acoustic vector sensors(AVS).The unique characteristics offered by these PZN–PT single crystal devices are highlighted,which serve as examples of newgeneration piezoelectric devices and systems for a wide range of demanding applications.展开更多
The dielectric properties of Pb(Zn1/3Nb2/3)O3-PbZrO3-PbTiO3 (PZN-PZ-PT) system near the rhombohedral/tetragonal morphotropic phase boundary (MPB) are carefully studied in this paper.It is found that,for all samples,th...The dielectric properties of Pb(Zn1/3Nb2/3)O3-PbZrO3-PbTiO3 (PZN-PZ-PT) system near the rhombohedral/tetragonal morphotropic phase boundary (MPB) are carefully studied in this paper.It is found that,for all samples,the curves around the temperatures of dielectric permittivity peak show the characteristics of diffuse phase transition.The change in PbZrO3/PbTiO3 ratio has much influence on the dielectric properties of the samples.The extent of diffuse phase transition increases with the increasing Zr/Ti ratio.The samples in rhombohedral region have typical diffuse phase transition in the temperature range measured.However,for the samples with tetragonal symmetry,a spontaneous normal ferroelectric-relaxor phase transition exists at temperature lower than that of permittivity peak.This normal ferroelectric-relaxor phase transition is confirmed by the experiment of thermally driven current.The analysis of TEM reveals that the samples in tetragonal region show a 90° macrodomain structure,while the samples in rhombohedral region have the configuration of microdomain structure.展开更多
文摘The integration of ferroelectric materials as thin films has attracted considerable attention these last years thanks to their outstanding performances that allow considering new features for the realization of photovoltaic devices. Our study focuses on investigating structural, dielectric and ferroelectric properties of undoped and Mn doped PZN-4.5PT nanoparticles thin films on Silicon substrate. We fabricate very stable PZN-4.5PT nanoparticles thin films deposited on nanostructured silicon substrate with giant relative dielectric permittivity of 2.76 × 104 and 17.7 × 104 for respectively the undoped and Mn doped thin films. These values are very large compared to those found in single crystals and might be explained by the influence of the gel in which nanoparticles were dispersed. The SEM images show the crystallization of new hexagonal phases on the film surface probably coming from interaction between Si and the gel. The hysteresis loops permitted to determine the spontaneous polarization (Ps), remnant polarization (Pr) and coercive field Ec which are equal to 11.73 μC/cm2, 10.20 μC/cm2 and 20 V/cm, respectively for the undoped nanoparticles thin film and 22.22 μC/cm2, 19.32 μC/cm2 and 20 V/cm respectively for the Mn doped one. These values are high and correspond to the best ones found in literature compared to typical ferroelectric thin films.
文摘This paper describes recent device developments with relaxor ferroelectric Pb(Zn_(1/3)Nb_(2/3))O_(3)-PbTiO_(3)(PZN–PT)single crystals carried out at Microfine Materials Technologies Pte.Ltd,Singapore.Promising[011]-poled transverse cuts of PZN–PT single crystals and the results on the effect of electric field and axial compressive stress on the rhombohedral-to-orthorhombic(R–O)phase transformation behavior of such cuts are presented and discussed.The single crystal devices described include a compact lowfrequency broadband power-efficient underwater tonpilz projector,high sensitivity shear accelerometers and acoustic vector sensors(AVS).The unique characteristics offered by these PZN–PT single crystal devices are highlighted,which serve as examples of newgeneration piezoelectric devices and systems for a wide range of demanding applications.
文摘The dielectric properties of Pb(Zn1/3Nb2/3)O3-PbZrO3-PbTiO3 (PZN-PZ-PT) system near the rhombohedral/tetragonal morphotropic phase boundary (MPB) are carefully studied in this paper.It is found that,for all samples,the curves around the temperatures of dielectric permittivity peak show the characteristics of diffuse phase transition.The change in PbZrO3/PbTiO3 ratio has much influence on the dielectric properties of the samples.The extent of diffuse phase transition increases with the increasing Zr/Ti ratio.The samples in rhombohedral region have typical diffuse phase transition in the temperature range measured.However,for the samples with tetragonal symmetry,a spontaneous normal ferroelectric-relaxor phase transition exists at temperature lower than that of permittivity peak.This normal ferroelectric-relaxor phase transition is confirmed by the experiment of thermally driven current.The analysis of TEM reveals that the samples in tetragonal region show a 90° macrodomain structure,while the samples in rhombohedral region have the configuration of microdomain structure.
