Potassium niobate modified BT-KBT-based energy storage ceramic and preparation method thereof
Technical Field
The invention belongs to the technical field of material preparation, and particularly relates to potassium niobate modified BT-KBT-based energy storage ceramic and a preparation method thereof.
Background
As an important energy storage device, a capacitor is one of electronic components widely used in electronic devices. The ceramic capacitor has the advantages of wide temperature range, long service life, reliable performance and the like, and is widely used. The stored energy of the capacitor is easy to maintain, and a superconductor is not needed. The capacitor energy storage is also important to provide instant high power, and is very suitable for application occasions such as lasers, flash lamps and the like. The amount of energy stored by the capacitor is determined by its size and the storage density of the dielectric material. In order to reduce the size and improve the energy storage capacity, the ceramic dielectric material with high energy storage density is developed to effectively solve the problem. The ceramic capacitor has the advantages of wide use temperature range, long service life, reliable performance and the like, and is widely used. The ferroelectric ceramic material has the advantages of large dielectric constant, strong nonlinear effect and the like, and the energy storage density J of the ferroelectric ceramic material in unit volume can be calculated by the following formula:
J=∫EdP
where P is the polarization and E is its breakdown strength.
The energy storage density of ferroelectric ceramic materials is determined by their minimum polarization strength (P)r) Maximum polarization intensity (P)m) And breakdown strength (E)b) And (4) jointly determining. However, Ba is widely studied0.4Sr0.6TiO3The energy storage density of the ceramic is only 0.37J/cm3The energy storage density is lower.
Disclosure of Invention
The invention aims to provide a potassium niobate modified BT-KBT-based energy storage ceramic and a preparation method thereofThe energy storage density of the ceramic material prepared by the method is up to 0.97J/cm3And the preparation method is simple and easy to realize.
The invention is realized by the following technical scheme:
the invention discloses a potassium niobate modified BT-KBT-based energy storage ceramic, which comprises the following chemical components: (1-x) (0.92 BaTiO)3-0.08(K1/2Bi1/2)TiO3)-xKNbO3(ii) a Wherein, the value range of x is 0.04-0.10.
Preferably, the energy storage density of the BT-KBT-based energy storage ceramic is 0.89-0.97J/cm3。
The invention also discloses a preparation method of the potassium niobate modified BT-KBT-based energy storage ceramic, which comprises the steps of mixing BT ceramic powder, KBT ceramic powder and potassium niobate powder according to a chemical formula (1-x) (0.92 BaTiO)3-0.08(K1/2Bi1/2)TiO3)-xKNbO3Preparing materials, uniformly mixing, forming, keeping the temperature at 1130-1170 ℃ for 2-6 h, and sintering to obtain a BT-KBT-based high energy storage density ceramic material; wherein, the value range of x is 0.04-0.10.
Preferably, the mixing is realized by ball milling, and deionized water is used as a ball milling medium.
Further preferably, the ball milling time is 6-8 h.
Preferably, the mixture is dried at 75-90 ℃ after being uniformly mixed.
Preferably, the BT ceramic powder is prepared by the following method:
according to the chemical formula BaTiO3The barium carbonate and the titanium dioxide are uniformly mixed and then are kept warm for 3 hours at 1150 ℃, and the BT ceramic powder is prepared.
Preferably, the KBT ceramic powder is prepared by the following method:
according to the chemical formula K0.5Bi0.5TiO3The KBT ceramic powder is prepared by uniformly mixing potassium carbonate, bismuth oxide and titanium dioxide, and then keeping the temperature at 950 ℃ for 4 hours.
Preferably, the potassium niobate ceramic powder is prepared by the following method:
according to the formula KNbO3The potassium niobate ceramic powder is prepared by uniformly mixing potassium carbonate and niobium pentoxide and then preserving the heat for 2 hours at 800 ℃.
Compared with the prior art, the invention has the following beneficial technical effects:
the invention reduces the saturation polarization strength by adding potassium niobate, thereby preparing the ceramic material with high energy storage density, because of 0.92BaTiO3-0.08(K1/2Bi1/2)TiO3Has higher maximum polarization intensity (P)m~42.52μC/cm3) But its remanent polarization is high (P)r~36.71μC/cm3) So that the energy storage density is lower (0.46J/cm)3) Due to K in potassium niobate+,Nb5+The crystal lattice distortion is caused when the crystal lattice is entered, the ceramic phase structure is changed from a tetragonal phase to a pseudo-cubic phase, the ferroelectricity is weakened, and the residual polarization intensity of the ceramic phase structure can be effectively reduced, so that the invention is directed to 0.92BaTiO3-0.08(K1/2Bi1/2)TiO3Adding a proper amount of KNbO3To reduce its remanent polarization and thereby obtain a ceramic material with a high energy storage density.
The invention takes barium carbonate, potassium carbonate, bismuth oxide, titanium dioxide and niobium pentoxide as raw materials to prepare (1-x) (0.92 BaTiO) by a solid phase method3-0.08(K1/2Bi1/2)TiO3)-xKNbO3The energy storage density of the ceramic material is up to 0.89-0.97J/cm3. The preparation method has the advantages of simple equipment, simple operation and low cost, can realize large-scale production, and provides a foundation for preparing the high-energy-density ceramic material in a large scale and at low cost.
Drawings
Fig. 1 is a graph of the hysteresis loop of a ceramic material with x being 0.04.
Fig. 2 is a graph of the hysteresis loop of the ceramic material with x being 0.08.
Fig. 3 is a graph of the hysteresis loop of the ceramic material with x being 0.10.
Detailed Description
The present invention will now be described in further detail with reference to specific examples, which are intended to be illustrative, but not limiting, of the invention.
Example 1
A preparation method of a potassium niobate modified BT-KBT based energy storage ceramic material comprises the following steps:
1) according to the chemical formula BaTiO3(BT), uniformly mixing barium carbonate and titanium dioxide, and then keeping the temperature for 3 hours at 1150 ℃ to prepare BT ceramic powder. (ii) a
2) According to the chemical formula K0.5Bi0.5TiO3(KBT), mixing the potassium carbonate, the bismuth oxide and the titanium dioxide evenly, and then preserving the heat for 4 hours at 950 ℃ to prepare KBT ceramic powder.
3) According to the formula KNbO3(KN), mixing the potassium carbonate and the niobium pentoxide uniformly, and then keeping the temperature at 800 ℃ for 2h to prepare the potassium niobate ceramic powder.
4) Mixing BT ceramic powder, KBT ceramic powder and potassium niobate powder according to chemical formula 0.96(0.92 BaTiO)3-0.08(K1/2Bi1/2)TiO3)-0.04KNbO3Proportioning, ball-milling for 6h by using deionized water as a ball-milling medium, uniformly mixing, drying at 80 ℃, tabletting, forming, and sintering at 1170 ℃ for 2h to obtain the ceramic material with high energy storage density.
Example 2
A preparation method of a potassium niobate modified BT-KBT based energy storage ceramic material comprises the following steps:
1) according to the chemical formula BaTiO3(BT), uniformly mixing barium carbonate and titanium dioxide, and then keeping the temperature for 3 hours at 1150 ℃ to prepare BT ceramic powder. (ii) a
2) According to the chemical formula K0.5Bi0.5TiO3(KBT), mixing the potassium carbonate, the bismuth oxide and the titanium dioxide evenly, and then preserving the heat for 4 hours at 950 ℃ to prepare KBT ceramic powder.
3) According to the formula KNbO3(KN), mixing the potassium carbonate and the niobium pentoxide uniformly, and then keeping the temperature at 800 ℃ for 2h to prepare the potassium niobate ceramic powder.
4) Mixing BT ceramic powder, KBT ceramic powder and potassium niobate powder according to chemical formula 0.96 (0).92BaTiO3-0.08(K1/2Bi1/2)TiO3)-0.04KNbO3Proportioning, ball-milling for 6h by using deionized water as a ball-milling medium, uniformly mixing, drying at 80 ℃, tabletting, forming, and sintering at 1170 ℃ for 4h to obtain the ceramic material with high energy storage density.
Example 3
A preparation method of a potassium niobate modified BT-KBT based energy storage ceramic material comprises the following steps:
1) according to the chemical formula BaTiO3(BT), uniformly mixing barium carbonate and titanium dioxide, and then keeping the temperature for 3 hours at 1150 ℃ to prepare BT ceramic powder. (ii) a
2) According to the chemical formula K0.5Bi0.5TiO3(KBT), mixing the potassium carbonate, the bismuth oxide and the titanium dioxide evenly, and then preserving the heat for 4 hours at 950 ℃ to prepare KBT ceramic powder.
3) According to the formula KNbO3(KN), mixing the potassium carbonate and the niobium pentoxide uniformly, and then keeping the temperature at 800 ℃ for 2h to prepare the potassium niobate ceramic powder.
4) Mixing BT ceramic powder, KBT ceramic powder and potassium niobate powder according to chemical formula 0.96(0.92 BaTiO)3-0.08(K1/2Bi1/2)TiO3)-0.04KNbO3Proportioning, ball-milling for 6h by using deionized water as a ball-milling medium, uniformly mixing, drying at 80 ℃, tabletting, forming, and sintering at 1170 ℃ for 6h to obtain the ceramic material with high energy storage density.
Example 4
A preparation method of a potassium niobate modified BT-KBT based energy storage ceramic material comprises the following steps:
1) according to the chemical formula BaTiO3(BT), uniformly mixing barium carbonate and titanium dioxide, and then keeping the temperature for 3 hours at 1150 ℃ to prepare BT ceramic powder. (ii) a
2) According to the chemical formula K0.5Bi0.5TiO3(KBT), mixing the potassium carbonate, the bismuth oxide and the titanium dioxide evenly, and then preserving the heat for 4 hours at 950 ℃ to prepare KBT ceramic powder.
3) According to the formula KNbO3(KN) reacting potassium carbonate and pentaoxideAnd uniformly mixing niobium and niobium, and then keeping the temperature at 800 ℃ for 2 hours to prepare the potassium niobate ceramic powder.
4) BT ceramic powder, KBT ceramic powder and potassium niobate powder are mixed according to a chemical formula of 0.92(0.92 BaTiO)3-0.08(K1/2Bi1/2)TiO3)-0.08KNbO3Proportioning, ball-milling for 6h by using deionized water as a ball-milling medium, uniformly mixing, drying at 80 ℃, tabletting, forming, and sintering at 1170 ℃ for 2h to obtain the ceramic material with high energy storage density.
Example 5
A preparation method of a potassium niobate modified BT-KBT based energy storage ceramic material comprises the following steps:
1) according to the chemical formula BaTiO3(BT), uniformly mixing barium carbonate and titanium dioxide, and then keeping the temperature for 3 hours at 1150 ℃ to prepare BT ceramic powder. (ii) a
2) According to the chemical formula K0.5Bi0.5TiO3(KBT), mixing the potassium carbonate, the bismuth oxide and the titanium dioxide evenly, and then preserving the heat for 4 hours at 950 ℃ to prepare KBT ceramic powder.
3) According to the formula KNbO3(KN), mixing the potassium carbonate and the niobium pentoxide uniformly, and then keeping the temperature at 800 ℃ for 2h to prepare the potassium niobate ceramic powder.
4) BT ceramic powder, KBT ceramic powder and potassium niobate powder are mixed according to a chemical formula of 0.92(0.92 BaTiO)3-0.08(K1/2Bi1/2)TiO3)-0.08KNbO3Proportioning, ball-milling for 6h by using deionized water as a ball-milling medium, uniformly mixing, drying at 80 ℃, tabletting, forming, and sintering at 1170 ℃ for 4h to obtain the ceramic material with high energy storage density.
Example 6
A preparation method of a potassium niobate modified BT-KBT based energy storage ceramic material comprises the following steps:
1) according to the chemical formula BaTiO3(BT), uniformly mixing barium carbonate and titanium dioxide, and then keeping the temperature for 3 hours at 1150 ℃ to prepare BT ceramic powder. (ii) a
2) According to the chemical formula K0.5Bi0.5TiO3(KBT) reaction of potassium carbonate,And uniformly mixing bismuth oxide and titanium dioxide, and then keeping the temperature for 4 hours at 950 ℃ to prepare the KBT ceramic powder.
3) According to the formula KNbO3(KN), mixing the potassium carbonate and the niobium pentoxide uniformly, and then keeping the temperature at 800 ℃ for 2h to prepare the potassium niobate ceramic powder.
4) BT ceramic powder, KBT ceramic powder and potassium niobate powder are mixed according to a chemical formula of 0.92(0.92 BaTiO)3-0.08(K1/2Bi1/2)TiO3)-0.08KNbO3Proportioning, ball-milling for 6h by using deionized water as a ball-milling medium, uniformly mixing, drying at 80 ℃, tabletting, forming, and sintering at 1170 ℃ for 6h to obtain the ceramic material with high energy storage density.
Example 7
A preparation method of a potassium niobate modified BT-KBT based energy storage ceramic material comprises the following steps:
1) according to the chemical formula BaTiO3(BT), uniformly mixing barium carbonate and titanium dioxide, and then keeping the temperature for 3 hours at 1150 ℃ to prepare BT ceramic powder. (ii) a
2) According to the chemical formula K0.5Bi0.5TiO3(KBT), mixing the potassium carbonate, the bismuth oxide and the titanium dioxide evenly, and then preserving the heat for 4 hours at 950 ℃ to prepare KBT ceramic powder.
3) According to the formula KNbO3(KN), mixing the potassium carbonate and the niobium pentoxide uniformly, and then keeping the temperature at 800 ℃ for 2h to prepare the potassium niobate ceramic powder.
4) Mixing BT ceramic powder, KBT ceramic powder and potassium niobate powder according to chemical formula 0.90(0.92 BaTiO)3-0.08(K1/2Bi1/2)TiO3)-0.10KNbO3Proportioning, ball-milling for 6h by using deionized water as a ball-milling medium, uniformly mixing, drying at 80 ℃, tabletting, forming, and sintering at 1170 ℃ for 2h to obtain the ceramic material with high energy storage density.
Example 8
A preparation method of a potassium niobate modified BT-KBT based energy storage ceramic material comprises the following steps:
1) according to the chemical formula BaTiO3(BT) mixing barium carbonate and titanium dioxideUniformly mixing, and keeping the temperature for 3h at 1150 ℃ to obtain the BT ceramic powder. (ii) a
2) According to the chemical formula K0.5Bi0.5TiO3(KBT), mixing the potassium carbonate, the bismuth oxide and the titanium dioxide evenly, and then preserving the heat for 4 hours at 950 ℃ to prepare KBT ceramic powder.
3) According to the formula KNbO3(KN), mixing the potassium carbonate and the niobium pentoxide uniformly, and then keeping the temperature at 800 ℃ for 2h to prepare the potassium niobate ceramic powder.
4) Mixing BT ceramic powder, KBT ceramic powder and potassium niobate powder according to chemical formula 0.90(0.92 BaTiO)3-0.08(K1/2Bi1/2)TiO3)-0.10KNbO3Proportioning, ball-milling for 6h by using deionized water as a ball-milling medium, uniformly mixing, drying at 80 ℃, tabletting, forming, and sintering at 1170 ℃ for 4h to obtain the ceramic material with high energy storage density.
Example 9
A preparation method of a potassium niobate modified BT-KBT based energy storage ceramic material comprises the following steps:
1) according to the chemical formula BaTiO3(BT), uniformly mixing barium carbonate and titanium dioxide, and then keeping the temperature for 3 hours at 1150 ℃ to prepare BT ceramic powder. (ii) a
2) According to the chemical formula K0.5Bi0.5TiO3(KBT), mixing the potassium carbonate, the bismuth oxide and the titanium dioxide evenly, and then preserving the heat for 4 hours at 950 ℃ to prepare KBT ceramic powder.
3) According to the formula KNbO3(KN), mixing the potassium carbonate and the niobium pentoxide uniformly, and then keeping the temperature at 800 ℃ for 2h to prepare the potassium niobate ceramic powder.
4) Mixing BT ceramic powder, KBT ceramic powder and potassium niobate powder according to chemical formula 0.90(0.92 BaTiO)3-0.08(K1/2Bi1/2)TiO3)-0.10KNbO3Proportioning, ball-milling for 6h by using deionized water as a ball-milling medium, uniformly mixing, drying at 80 ℃, tabletting, forming, and sintering at 1170 ℃ for 6h to obtain the ceramic material with high energy storage density.
Referring to FIG. 1, the hysteresis of the ceramic sample prepared in example 1 is shownThe energy storage density of the sample can reach 0.93J/cm3And the energy storage efficiency can reach 44.38%. FIG. 2 is a graph showing the hysteresis loop of the ceramic sample prepared in example 4, from which it can be seen that the energy storage density of the sample can be up to 0.89J/cm3And the energy storage efficiency can reach 55.62%. FIG. 3 is a graph showing the hysteresis loop of the ceramic sample prepared in example 7, from which it can be seen that the energy storage density of the sample can be up to 0.97J/cm3And the energy storage efficiency can reach 55.1%.