scholarly journals Defect engineering of BCZT-based piezoelectric ceramics with high piezoelectric properties

2021 ◽  
Vol 11 (1) ◽  
pp. 184-195
Author(s):  
Xinjian Wang ◽  
Yu Huan ◽  
Yixuan Zhu ◽  
Peng Zhang ◽  
Wenlong Yang ◽  
...  
Keyword(s):  
Oxygen Partial Pressure ◽  
Partial Pressure ◽  
Conduction Mechanism ◽  
Piezoelectric Properties ◽  
Hole Concentration ◽  
Doping Element ◽  
Mn Doping ◽  
Mechanical Coupling ◽  
Intrinsic Conduction ◽  
Mn Doped

AbstractThe intrinsic conduction mechanism and optimal sintering atmosphere of (Ba0.85Ca0.15)(Zr0.1Ti0.9)O3 (BCZT) ceramics were regulated by Mn-doping element in this work. By Hall and impedance analysis, the undoped BCZT ceramics exhibit a typical n-type conduction mechanism, and the electron concentration decreases with the increasing oxygen partial pressure. Therefore, the undoped ceramics exhibit best electrical properties (piezoelectrical constant d33 = 585 pC·N−1, electro-mechanical coupling factor kp = 56%) in O2. A handful of Mn-doping element would transfer the conduction mechanism from n-type into p-type. And the hole concentration reduces with the decreasing oxygen partial pressure for Mn-doped BCZT ceramics. Therefore, the Mn-doped ceramics sintered in N2 have the highest insulation resistance and best piezoelectric properties (d33 = 505 pC·N−1, kp = 50%). The experimental results demonstrate that the Mn-doping element can effectively adjust the intrinsic conduction mechanism and then predict the optimal atmosphere.

Defect Engineering of BCZT–based Piezoelectric Ceramics with High Piezoelectric Properties

2021 ◽  
Author(s):  
Xinjian Wang ◽  
Yu Huan ◽  
Yixuan Zhu ◽  
Peng Zhang ◽  
Wenlong Yang ◽  
...  
Keyword(s):  
Oxygen Partial Pressure ◽  
Partial Pressure ◽  
Conduction Mechanism ◽  
Piezoelectric Properties ◽  
Hole Concentration ◽  
Impedance Analysis ◽  
Defect Engineering ◽  
Intrinsic Conduction ◽  
P Type ◽  
Mn Doped

Abstract The intrinsic conduction mechanism and optimal sintering atmosphere of (Ba0.85Ca0.15)(Zr0.1Ti0.9)O3 (BCZT) ceramics was regulated by doping Mn element in this work. By Hall and impedance analysis, the undoped BCZT ceramics exhibit a typical n–type conduction mechanism, and the electron concentration decreases with the increasing oxygen partial pressure. Therefore, the undoped ceramics exhibit best electrical properties (d33 = 585 pC/N, kp = 56%) in O2. A handful of Mn doping element would transfer the conduction mechanism from n-type into p–type. And the hole concentration reduces with the decreasing oxygen partial pressure for Mn-doped BCZT ceramics. Therefore, the Mn-doped ceramics sintered in N2 have the highest insulation resistance and best piezoelectric properties (d33 = 505 pC/N, kp = 50%). The experimental results demonstrate that the doping Mn element can effectively adjusts the intrinsic conduction mechanism and then predicts the optimal atmosphere.

Electrical Properties of Donor and Acceptor Doped Gd2Ti2O7

1994 ◽  
Vol 369 ◽  
Author(s):  
Igor Kosacki ◽  
Harry L. Tuller
Keyword(s):  
Electrical Conductivity ◽  
Electrical Properties ◽  
Oxygen Partial Pressure ◽  
Partial Pressure ◽  
Conductivity Measurements ◽  
Donor And Acceptor ◽  
Mn Doped

The results of electrical conductivity measurements on Nb, W, and Mn-doped Gd2Ti2O7 are presented. A correlation between electrical conductivity, the oxygen partial pressure and type of dopants has been obtained. The source of the different PO2 dependence for Mn-doped material is discussed.

Synthesis and Properties of the High Tc Bi-Pb-Sr-Ca-Cu-O Superconductors

1989 ◽  
Vol 156 ◽  
Author(s):  
Utako Endo ◽  
J. Koyama ◽  
T. Kawai ◽  
N. Okazaki ◽  
K. Kitazawa ◽  
...  
Keyword(s):  
Oxygen Partial Pressure ◽  
Partial Pressure ◽  
Hole Concentration ◽  
Composition Analysis ◽  
Low Oxygen ◽  
High Tc ◽  
Atomic Site ◽  
High Tc Phase

ABSTRACTA single high Tc phase of Bi-Pb-Sr-Ca-Cu-O superconductor was obtained by following proper synthetic conditions:(a)addition of Pb, (b)proper starting composition, (c)codecomposition method, (d)sintering under low oxygen partial pressure and (e)long sintering. The composition analysis showed that every atomic site might be occupied by some element and there might not be defects or excess atoms in the structure. The hole donor in these samples is considered to be Pb on the Bi site and hole concentration seems to be, to some extent, controlled by the Pb content. A phase with four CuO2 layers have possibly grown on the surface of the grains of thi high Tc phase.

scholarly journals Electrical and Magnetic Properties of Polycrystalline Mn-Doped BaTiO3 Thin Films Grown on Pt/Sapphire Substrates by Pulsed Laser Deposition

2010 ◽  
Vol 67 ◽  
pp. 212-217 ◽  
Author(s):  
Yao Shuai ◽  
Sheng Qiang Zhou ◽  
Heidemarie Schmidt
Keyword(s):  
Thin Films ◽  
Oxygen Partial Pressure ◽  
Partial Pressure ◽  
Pulsed Laser Deposition ◽  
Pulsed Laser ◽  
Laser Deposition ◽  
Magnetic Polaron ◽  
Low Oxygen ◽  
Sapphire Substrates ◽  
Mn Doped

5 at.% Mn-doped and undoped, 200 nm thick BaTiO3 thin films have been grown under different oxygen partial pressures by pulsed laser deposition on Pt/sapphire substrates. X-ray diffraction (XRD) measurements reveal the same polycrystalline single-phase perovskite structure for all the thin films despite the different oxygen partial pressure, while their preferred orientation strongly depends on the oxygen partial pressure. The 5 at. % Mn-doping decreases the dielectric loss of the Mn-doped BaTiO3 thin films, however, their relative permittivity is also decreased. Ferroelectricity has been probed on the Mn-doped and undoped BaTiO3 thin films grown under relatively high oxygen partial pressure. A ferromagnetic coupling of the Mn dopant ions has been probed at room tempetature on the Mn-doped BaTiO3 thin films prepared under low oxygen partial pressure and is understood in terms of the bound magnetic polaron model.

Effect of Growth Condition on the Electrical and Magnetic Properties of Sputtered ZnCo2O4 Films

2004 ◽  
Vol 449-452 ◽  
pp. 509-512 ◽  
Author(s):  
Hyun Jung Kim ◽  
In Chang Song ◽  
Jae Ho Sim ◽  
Hyo Jin Kim ◽  
Do Jin Kim ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Oxygen Partial Pressure ◽  
Partial Pressure ◽  
Hole Concentration ◽  
Pressure Ratio ◽  
Antiferromagnetic Coupling ◽  
Ferromagnetic Transition ◽  
Electrical And Magnetic Properties ◽  
P Type ◽  
Partial Pressure Ratio

We report on the effect of the oxygen partial pressure ratio in the sputtering gas mixture on the electrical and magnetic properties of cubic spinel ZnCo2O4 thin films grown by reactive magnetron sputtering. The conduction type and carrier concentration in ZnCo2O4 films were found to be dependent on the oxygen partial pressure ratio. The maximum electron and hole concentration at 300 K were estimated to be as high as 1.37 × 1020 cm-3 and 2.81 × 1020 cm-3, respectively. While an antiferromagnetic coupling was found for n-type ZnCo2O4, a ferromagnetic interaction was observable in p-type ZnCo2O4, indicating hole-induced ferromagnetic transition in spinel ZnCo2O4.

Electrical Conductivity of Piezoelectric Strontium Bismuth Titanate Under Controlled Oxygen Partial Pressure

1999 ◽  
Vol 604 ◽  
Author(s):  
C. Voisard ◽  
P. Duran Martin ◽  
D. Damjanovic ◽  
N. Settier
Keyword(s):  
Electrical Conductivity ◽  
Oxygen Partial Pressure ◽  
Partial Pressure ◽  
Elevated Temperatures ◽  
Vacancy Concentration ◽  
Common Mechanism ◽  
Oxygen Vacancy Concentration ◽  
Reducing Conditions ◽  
Ionic Transport Number ◽  
Mn Doped

AbstractHysteresis free and linear piezoelectric behavior of SrBi4Ti4O15 (SrBIT) is very promising for precise sensors/actuators devices. Despite a quite low longitudinal piezoelectric coefficient (around 15 pC/N), its elevated ferroelectric phase transition temperature (540°C) allows its use above 300°C. Electrical conductivity at such temperatures should be kept as low as possible in order to avoid loss of piezoelectric properties or charge drifts. Under reducing conditions, however, the electrical conductivity may change considerably. The electrical conductivity of SrBi4Ti4O15 (SrBIT) has been measured under controlled oxygen partial pressure at elevated temperatures (700-900°C) from 1 atm down to 10−15atm. From 1 atm down to 10−15 atm pO2, above 700°C, the conductivity of SrBIT exhibits a -1/4 slope in log-log scale indicating n-type conductivity and an impurity controlled oxygen vacancy concentration. A conductivity minimum is observed around 0.2 atm for undoped SrBIT at 800°C. Acceptor doping (Mn) raises the minimum and flattens the conductivity curve with slope around -1/10 at 700°C, and -1/6 at 900°C. Ionic conductivity and defect ionization are discussed to account for this. Preliminary results indicate the possibility of a large, pO2 independent, region, down to 10−15atm pO2. The ionic transport number was found to be 0.42 at 800°C for undoped SrBIT and 0.75 for Mn doped SrBIT. The activation energies of undoped (1.35 eV) and Mn doped (1.44 eV) samples are close to each other as expected for a common mechanism

scholarly journals Manganese-doping enhanced local heterogeneity and piezoelectric properties in potassium tantalate niobate single crystals

IUCrJ ◽  
2021 ◽  
Vol 8 (2) ◽  
pp. 319-326
Author(s):  
Yu Wang ◽  
Peng Tan ◽  
Xiangda Meng ◽  
Zhongxiang Zhou ◽  
Xiaolin Huang ◽  
...  
Keyword(s):  
Material Properties ◽  
Piezoelectric Properties ◽  
Mn Doping ◽  
Manganese Doping ◽  
Potassium Tantalate Niobate ◽  
Ion Doping ◽  
Local Heterogeneity ◽  
The Impact ◽  
Mn Doped

Ion doping, an effective way to modify the nature of materials, is beneficial for the improvement of material properties. Mn doping exhibits gain of piezoelectric properties in KTa1−x Nb x O3 (KTN). However, the impact mechanism of Mn ions on properties remains unclear. Here, the effects of Mn doping on local heterogeneity and piezoelectric properties in KTN are studied. The electric field-induced strain of Mn-doped KTN is ∼0.25% at 10 kV cm−1, 118% higher than that of pristine KTN. Meanwhile, as a result of Mn doping, the dielectric permittivity was tripled and the ferroelectricity was modified. The changes in A1(2TO), B1 + E(3TO) and E(4TO) vibrations characterized by Raman spectra indicate increased local polarization, weak correlation of dipoles and distorted lattices in Mn-doped KTN, respectively. First-principles calculations demonstrate stronger local heterogeneity introduced by Mn dopants, which weakens the dipole correlations and reduces domain sizes. As a result, the decreased domain sizes, combined with the larger ratio of lattice parameters c and a of the Mn-contained portion, are responsible for the higher piezoelectricity. This work reveals the impact on properties of KTN from Mn dopants and the prominent role of local heterogeneity in improving piezoelectricity, being valuable for the optimization and design of material properties.

THERMOELECTRIC PROPERTIES OF MANGANESE-DOPED p-TYPE SKUTTERUDITES CeyFe4-xMnxSb12

2013 ◽  
Vol 06 (05) ◽  
pp. 1340003 ◽  
Author(s):  
PENGFEI QIU ◽  
XUN SHI ◽  
RUIHENG LIU ◽  
YUTING QIU ◽  
SHUN WAN ◽  
...  
Keyword(s):  
High Temperature ◽  
Thermoelectric Properties ◽  
Hole Concentration ◽  
Mn Doping ◽  
Maximum Value ◽  
The Matrix ◽  
Filled Skutterudites ◽  
P Type ◽  
Mn Doped ◽  
Thermal Conductivities

R y Fe 4 Sb 12-based filled skutterudites have been studied extensively as p-type legs used in high-temperature thermoelectric generator. One approach to further improve their thermoelectric performance is to optimize the overhigh hole concentration in R y Fe 4 Sb 12 skutterudite. In this study, we used element Mn doped on the skutterudite framework and systemically investigated the effects of Mn on the filler filling fractions, crystal structures, and high-temperature thermoelectric properties in Ce y Fe 4-x Mn x Sb 12. It is found that the Mn doping limit at Fe sites is around 0.15. Mn doping slightly enhances Ce filling fractions because Mn acts as an electron acceptor and its doping could push more electron donator Ce into the voids of skutterudites. Although Mn has one valence electron less than Fe , the excessive electrons donated by Ce fillers can completely compensate the holes generated by Mn and reduce the material's hole concentration, leading to a much reduced electrical conductivity and electrical thermal conductivity. Since the lattice thermal conductivities of Mn -doped samples are almost unchanged as compared with that of the matrix, the total thermal conductivities are obviously decreased. Meanwhile, high power factors are maintained in Mn -doped samples because of the enhanced Seebeck coefficient as well as the undegraded carrier mobility. As a combined effect, the figure of merit in Mn -doped samples is much improved in the whole temperature range. Sample CeFe 3.85 Mn 0.15 Sb 12 exhibits a maximum value of 0.98 at 800 K among all the samples investigated in this work.

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