CN109111126B - Mn-doped composite film for regulating resistance switching effect and preparation method thereof - Google Patents
Mn-doped composite film for regulating resistance switching effect and preparation method thereof Download PDFInfo
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- 229910020912 Co1-xMnx Inorganic materials 0.000 claims abstract description 13
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- 239000000758 substrate Substances 0.000 claims description 94
- 239000011521 glass Substances 0.000 claims description 77
- 239000002243 precursor Substances 0.000 claims description 60
- VCJMYUPGQJHHFU-UHFFFAOYSA-N iron(3+);trinitrate Chemical compound [Fe+3].[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O VCJMYUPGQJHHFU-UHFFFAOYSA-N 0.000 claims description 48
- 238000003756 stirring Methods 0.000 claims description 48
- 239000011572 manganese Substances 0.000 claims description 47
- XNWFRZJHXBZDAG-UHFFFAOYSA-N 2-METHOXYETHANOL Chemical compound COCCO XNWFRZJHXBZDAG-UHFFFAOYSA-N 0.000 claims description 45
- 239000012528 membrane Substances 0.000 claims description 37
- UFMZWBIQTDUYBN-UHFFFAOYSA-N cobalt dinitrate Chemical compound [Co+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O UFMZWBIQTDUYBN-UHFFFAOYSA-N 0.000 claims description 24
- 229910001981 cobalt nitrate Inorganic materials 0.000 claims description 24
- 229910021645 metal ion Inorganic materials 0.000 claims description 24
- DHEQXMRUPNDRPG-UHFFFAOYSA-N strontium nitrate Chemical compound [Sr+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O DHEQXMRUPNDRPG-UHFFFAOYSA-N 0.000 claims description 24
- 229940071125 manganese acetate Drugs 0.000 claims description 23
- UOGMEBQRZBEZQT-UHFFFAOYSA-L manganese(2+);diacetate Chemical compound [Mn+2].CC([O-])=O.CC([O-])=O UOGMEBQRZBEZQT-UHFFFAOYSA-L 0.000 claims description 23
- RXPAJWPEYBDXOG-UHFFFAOYSA-N hydron;methyl 4-methoxypyridine-2-carboxylate;chloride Chemical compound Cl.COC(=O)C1=CC(OC)=CC=N1 RXPAJWPEYBDXOG-UHFFFAOYSA-N 0.000 claims description 21
- 239000011248 coating agent Substances 0.000 claims description 15
- 238000000576 coating method Methods 0.000 claims description 15
- 239000003292 glue Substances 0.000 claims description 14
- MWFSXYMZCVAQCC-UHFFFAOYSA-N gadolinium(iii) nitrate Chemical compound [Gd+3].[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O MWFSXYMZCVAQCC-UHFFFAOYSA-N 0.000 claims description 12
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- 230000005621 ferroelectricity Effects 0.000 abstract description 7
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- 230000008569 process Effects 0.000 abstract description 4
- 239000010408 film Substances 0.000 description 210
- 230000003749 cleanliness Effects 0.000 description 19
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- 229910002902 BiFeO3 Inorganic materials 0.000 description 7
- 230000005415 magnetization Effects 0.000 description 6
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- 229910002518 CoFe2O4 Inorganic materials 0.000 description 5
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 4
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- 229910018669 Mn—Co Inorganic materials 0.000 description 1
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- 229910000859 α-Fe Inorganic materials 0.000 description 1
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- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C17/00—Surface treatment of glass, not in the form of fibres or filaments, by coating
- C03C17/34—Surface treatment of glass, not in the form of fibres or filaments, by coating with at least two coatings having different compositions
- C03C17/3411—Surface treatment of glass, not in the form of fibres or filaments, by coating with at least two coatings having different compositions with at least two coatings of inorganic materials
- C03C17/3417—Surface treatment of glass, not in the form of fibres or filaments, by coating with at least two coatings having different compositions with at least two coatings of inorganic materials all coatings being oxide coatings
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- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C2217/00—Coatings on glass
- C03C2217/70—Properties of coatings
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- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C2217/00—Coatings on glass
- C03C2217/90—Other aspects of coatings
- C03C2217/94—Transparent conductive oxide layers [TCO] being part of a multilayer coating
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- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C2218/00—Methods for coating glass
- C03C2218/10—Deposition methods
- C03C2218/11—Deposition methods from solutions or suspensions
- C03C2218/116—Deposition methods from solutions or suspensions by spin-coating, centrifugation
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- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C2218/00—Methods for coating glass
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Abstract
The invention provides a Mn-doped composite film for regulating resistance switch effect and a preparation method thereof, comprising an upper layer film and a lower layer film which are compounded together; the upper film has a chemical formula of Bi0.88Gd0.09Sr0.03Fe0.94Mn0.04Co0.02O3The perovskite structure is a polycrystalline twisted perovskite structure, and the space group is R3 c; the underlayer film has the chemical formula of Co1‑xMnxFe2O4The cubic inverse spinel structure is provided, and the space group is Fd3m, wherein x is 0.1-0.7. Co is prepared by adopting a sol-gel spin-coating method and a layer-by-layer annealing process1‑xMnxFe2O4And preparing the BGSFMC film by a spin-coating method and a layer-by-layer annealing process to form the BGSFMC/C1-xMxFO composite film. The composite film of the invention has better ferroelectricity and resistance switching effect while increasing ferromagnetism.
Description
Technical Field
The invention belongs to the field of functional materials, and relates to a Mn-doped composite film for regulating and controlling a resistance switching effect and a preparation method thereof.
Background
With the rapid development of science and technology, the requirements for miniaturization and diversification of devices are higher and higher, so that the development of new materials with multiple functions to replace materials with single function is urgently needed to meet the requirement for developing novel multifunctional devices. Bismuth ferrite (BiFeO)3BFO), which is the only single-phase multiferroic material having ferroelectricity and antiferromagnetism at room temperature, has higher Curie temperature, Neille temperature and larger remanent polarization, and has good application prospect in the fields of ferroelectric random access memory, spin electronic device, magnetoelectric memory unit, photoelectric device, etc.
However, BiFeO3The bismuth element in the film is easy to volatilize and part of Fe3+To Fe2+Causes more oxygen vacancies to be generated in the thin film, resulting in BiFeO3Film existsThe serious leakage phenomenon and the large coercive field are difficult to polarize, and a high remanent polarization value is difficult to obtain, so that the practical application is limited. Further, BiFeO3The presence of weak ferromagnetism in thin films makes it difficult to meet the strong ferromagnetic coupling required for new generation memory devices and other multi-function devices. There is therefore a need for improved BiFeO3Multiferroic and ferromagnetic properties of the film. For improving BiFeO3The multiferroic and ferromagnetic properties of the thin film are most commonly obtained by doping multiple co-ions and compounding the magnetic film, but the ferroelectric property of the upper layer thin film is influenced after the magnetic film is added, the resistance switching characteristic of the compounded thin film is further influenced, and the practical application of the material is restricted.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides a Mn-doped composite film for regulating and controlling the resistance switching effect and a preparation method thereof, which can improve BiFeO3The multiferroic performance of the base film increases the resistance switching effect.
The invention is realized by the following technical scheme:
a Mn-doped composite film for regulating and controlling resistance switch effect comprises an upper layer film and a lower layer film which are compounded together; the upper film has a chemical formula of Bi0.88Gd0.09Sr0.03Fe0.94Mn0.04Co0.02O3The perovskite structure is a polycrystalline twisted perovskite structure, and the space group is R3 c; the underlayer film has the chemical formula of Co1-xMnxFe2O4The cubic inverse spinel structure is provided, and the space group is Fd3m, wherein x is 0.1-0.7.
Preferably, when x is 0.7, the ratio HRS/LRS of the high-low resistance state is 1.9; when x is 0.3, the remanent polarization value is 90.5-135 μ C/cm under 20-35V voltage2The electric hysteresis loop has a rectangular degree of Rsq1.07-1.12% of the total weight of the powder; when x is 0.3, under the action of an external magnetic field, the saturation magnetization value Ms is 43emu/cm3The residual magnetization value Mr is 28.5emu/cm3。
A preparation method of the Mn-doped composite film for regulating the resistance switching effect comprises the following steps,
step 1, dissolving cobalt nitrate, manganese acetate and ferric nitrate in ethylene glycol monomethyl ether, adding acetic anhydride after uniformly stirring, and continuously uniformly stirring to obtain a bottom layer membrane precursor solution;
step 2, spin-coating the bottom layer film precursor solution on an FTO/glass substrate to obtain a wet film, baking the wet film at 190-195 ℃ after spin-coating to obtain a dry film, and annealing in air at 660-710 ℃ to obtain crystalline Co1-xMnxFe2O4A film;
step 3, mixing the crystalline Co1-xMnxFe2O4Cooling the film, and repeating the step 2 until the preset thickness is reached to obtain a bottom layer film;
step 4, dissolving bismuth nitrate, gadolinium nitrate, strontium nitrate, ferric nitrate, manganese acetate and cobalt nitrate in ethylene glycol monomethyl ether, adding acetic anhydride after uniformly stirring, and continuously uniformly stirring to obtain an upper layer membrane precursor solution;
step 6: bi to be crystallized0.88Gd0.09Sr0.03Fe0.94Mn0.04Co0.02O3After the film is cooled, Bi is added0.88Gd0.09Sr0.0 3Fe0.94Mn0.04Co0.02O3And (5) repeating the step on the film to reach the preset thickness, thus obtaining the Mn-doped composite film for regulating the resistance switching effect.
Preferably, in the step 1, the total concentration of the metal ions in the underlayer coating precursor solution is 0.2 to 0.4 mol/L.
Preferably, in the step 4, the total concentration of the metal ions in the upper layer film precursor solution is 0.2-0.3 mol/L.
Preferably, the volume ratio of ethylene glycol monomethyl ether to acetic anhydride in the underlayer coating precursor solution and the overlayer coating precursor solution is (2.5-3.5): 1.
Preferably, in the step 2 and the step 5, the spin speed of spin coating is 3500-4000 r/min, and the spin time is 10-16 s.
Preferably, in the step 2 and the step 5, the baking time after the glue is homogenized is 8-10 min.
Preferably, the annealing time in the step 2 is 35-45 min.
Preferably, the annealing time in the step 5 is 25-35 min.
Compared with the prior art, the invention has the following beneficial technical effects:
the upper layer film Bi of the invention0.88Gd0.09Sr0.03Fe0.94Mn0.04Co0.02O3(BGSFMC for short) is in BiFeO3The A site is doped with rare earth elements Gd and alkaline earth metal Sr, the B site is doped with transition metals Mn and Co, and the bottom layer film Co1-xMnxFe2O4(abbreviated as C)1-xMxFO) is in CoFe2O4Middle doped Mn2+Ion obtaining, compounding upper layer film and bottom layer film to BGSFMC/C1-xMxFO composite membranes. The rare earth element is doped on the A position of the upper layer, so that the volatilization of Bi can be inhibited, the oxygen vacancy is reduced, the leakage current is further reduced, and the ferroelectric property of the film is effectively improved; the divalent alkali metal ions can compensate the charge imbalance caused by oxygen vacancy and effectively inhibit Fe3+The valence state of the ion fluctuates; fe can be inhibited by doping transition metal ions on the B site3+To Fe2+Switching, reducing the generation of oxygen vacancies, thereby improving ferroelectricity. The composite film of the invention has a voltage range of 20-35V and a remanent polarization value of 90.5-135 mu C/cm2The rectangle degree of the hysteresis loop is RsqThe stable ferroelectricity with variation with applied voltage is demonstrated at 1.07 to 1.12. Simultaneous compounding of CoFe2O4The magnetic film can improve the ferromagnetism of the film, and CoFe can prevent the composite magnetic film from influencing the ferroelectricity and resistance switching characteristics of the upper film2O4Middle doped Mn2+Ions in BGSFMC and C1-xMxThe interface of FO generates a rich Gd-Sr-MThe intermediate transition layer of n-Co ensures that the composite film has resistance switching effect. Therefore, after the magnetic film is compounded, the compounded film not only has better ferromagnetism, but also has better ferroelectricity and resistance switching characteristics.
The invention provides BGSFMC/C with resistance switching effect1-xMxThe preparation method of the FO double-layer composite film adopts a sol-gel spin-coating method and a layer-by-layer annealing process to prepare Co1-xMnxFe2O4Preparing the BGSFMC film by a spin-coating method and a layer-by-layer annealing process to form BGSFMC/C1-xMxCompared with other methods for preparing the thin film, the FO composite thin film adopts a sol-gel process, and the method has the advantages of simple equipment requirement, easy realization of experimental conditions, low cost, easy reaction, low temperature of the technological process, easy control of the preparation process and the doping amount, accurate and controllable chemical components, and suitability for preparing the thin film on large surfaces and irregular surfaces.
Drawings
FIG. 1 is BGSFMC/C prepared by the invention1-xMxXRD patterns of the FO composite thin film, FIG. 1(b) and FIG. 1(c) are respectively partial enlarged views of FIG. 1 (a);
FIG. 2 is BGSFMC/C prepared by the invention0.7M0.3The electric hysteresis loop of the FO composite film under different test voltages;
FIG. 3 is BGSFMC/C prepared by the invention0.3M0.7I-E loop plot of FO composite membranes;
FIG. 4 is BGSFMC/C prepared by the invention0.7M0.3Hysteresis loop plot of FO composite films.
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.
The invention relates to a Mn-doped composite film for regulating and controlling a resistance switching effect, in particular to Bi0.88Gd0.09Sr0.0 3Fe0.94Mn0.04Co0.02O3/Co1-xMnxFe2O4The upper layer film of the composite film is Bi with a polycrystal distorted perovskite structure and a space group of R3c0.88Gd0.09Sr0.03Fe0.94Mn0.04Co0.02O3(abbreviated as BGSFMC) film; the underlayer film is Co of cubic inverse spinel structure and space group Fd3m1-xMnxFe2O4(abbreviated as C)1-xMxFO) thin film, wherein x is 0.1 to 0.7.
BGSFMC/C1-xMxIn the FO composite film, in BGSFMC film and C1-xMxAn intermediate transition layer rich in Gd-Sr-Mn-Co is generated at the interface of the FO film, and the ratio HRS/LRS of the high-resistance state and the low-resistance state is 1.4-1.9 due to the formation of the intermediate layer, so that the composite film has a resistance switching effect.
BGSFMC/C0.97M0.3The FO composite thin film has a remanent polarization value of 90.5 to 135 [ mu ] C/cm at an applied voltage of 20 to 35V when x is 0.3 due to the formation of the intermediate layer2The rectangular degree of the hysteresis loop R of the symmetrical rectangular hysteresis loopsq1.07 to 1.12, and the composite film has stable ferroelectricity with voltage varying in the range of 20 to 35V. When x is 0.3, the saturation magnetization value M is increased due to the addition of the magnetic basement membranesIs 43emu/cm3Residual magnetization value MrIs 28.5emu/cm3The ferromagnetic performance is enhanced.
The BGSFMC/C with the resistance switching effect1-xMxThe preparation method of the FO composite film comprises the following steps:
step 1: dissolving cobalt nitrate, manganese acetate and ferric nitrate in ethylene glycol monomethyl ether according to a molar ratio of (1-x) x:2, adding acetic anhydride after uniformly stirring, and continuously uniformly stirring to obtain a bottom layer membrane precursor solution; wherein x is 0.1-0.7;
step 2: spin-coating the bottom layer film precursor solution on an FTO/glass substrate to obtain a wet film, baking the wet film at 190-195 ℃ after spin-coating to obtain a dry film, and annealing in air at 660-710 ℃ to obtain crystalline Co1-xMnxFe2O4A film;
and step 3: crystalline Co1-xMnxFe2O4Cooling the film to room temperature, repeating the step 2 until the preset thickness is reached, and obtaining the bottom layer of Co1-xMnxFe2O4A film.
And 4, step 4: dissolving bismuth nitrate, gadolinium nitrate, strontium nitrate, ferric nitrate, manganese acetate and cobalt nitrate in ethylene glycol monomethyl ether according to the molar ratio of 0.88:0.09:0.03:0.94:0.04:0.02, adding acetic anhydride after uniformly stirring, and continuously uniformly stirring to obtain an upper layer membrane precursor solution.
And 5: coating the precursor solution of the upper layer film on the bottom layer covered with Co obtained in the step 31-xMnxFe2O4And (3) obtaining a wet film on the FTO/glass substrate of the film, homogenizing the wet film, baking the wet film at 190-195 ℃ to obtain a dry film, and annealing the dry film in air at 550-600 ℃ to obtain the crystalline BGSFMC film.
Step 6: and (5) after the crystalline BGSFMC film is cooled, repeating the step 5 on the BGSFMC film to reach the preset thickness, and thus obtaining the Mn-doped composite film for regulating the resistance switching effect.
The total concentration of metal ions in the underlayer film precursor solution in the step 1 is 0.3-0.4 mol/L.
In the step 4, the total concentration of metal ions in the upper layer film precursor solution is 0.2-0.3 mol/L
In the bottom layer film precursor liquid and the upper layer film precursor liquid, the volume ratio of ethylene glycol monomethyl ether to acetic anhydride is (2.5-3.5): 1.
And 2, cleaning the FTO/glass substrate before the step is carried out, and then irradiating under ultraviolet light to ensure that the surface of the FTO/glass substrate reaches atomic cleanliness.
In the step 2 and the step 5, the spin speed of spin coating is 3500-4000 r/min, and the spin time is 10-16 s.
In the step 2 and the step 5, the baking time after glue homogenizing is 8-10 min.
And the annealing time in the step 2 is 35-45 min.
And the annealing time in the step 4 is 25-35 min.
Specific examples are as follows.
Example 1
Step 1: cleaning the FTO/glass substrate respectively with liquid detergent, acetone and absolute ethyl alcohol, and sealing in absolute ethyl alcohol for later use;
step 2: dissolving cobalt nitrate, manganese acetate and ferric nitrate serving as raw materials in ethylene glycol monomethyl ether according to a molar ratio of 0.9:0.1:2(x is 0.1), stirring for 30min, adding acetic anhydride, and stirring for 90min to obtain a stable bottom layer membrane precursor solution with the total metal ion concentration of 0.2 mol/L; wherein the volume ratio of the ethylene glycol monomethyl ether to the acetic anhydride is 3: 1;
and step 3: washing FTO/glass substrate with deionized water, and washing with N2Blow-drying, irradiating the clean FTO/glass substrate for 40min by using an ultraviolet light irradiation instrument to ensure that the surface of the FTO/glass substrate reaches atomic cleanliness, then spin-coating the bottom layer film precursor solution on the FTO/glass substrate at the spin-coating speed of 4000r/min for 10s to obtain a wet film, baking the wet film at 195 ℃ for 10min to obtain a dry film, and annealing in the air at 660 ℃ for 40min to obtain the crystalline Co0.9Mn0.1Fe2O4A film;
and 4, step 4: dissolving bismuth nitrate, gadolinium nitrate, strontium nitrate, ferric nitrate, manganese acetate and cobalt nitrate (the excessive amount of bismuth nitrate is 5%) in ethylene glycol monomethyl ether according to the molar ratio of 0.92:0.09:0.03:0.94:0.04:0.02, adding acetic anhydride after uniformly stirring, and continuously and uniformly stirring to obtain a stable upper layer membrane precursor solution with the total metal ion concentration of 0.3 mol/L; wherein the volume ratio of the ethylene glycol monomethyl ether to the acetic anhydride is 3: 1;
and 5: coating step 3 with crystalline Co0.9Mn0.1Fe2O4Irradiating the FTO/glass substrate with ultraviolet irradiation instrument for 40min to make the surface of the substrate reach atom cleanliness, and spin-coating the precursor solution of the upper layer film on the substrate covered with crystalline Co0.9Mn0.1Fe2O4And (3) on the FTO/glass substrate of the film, the spin coating speed is 4000r/min, the spin coating time is 10s, a wet film is obtained, the wet film is baked for 10min at 195 ℃ to obtain a dry film, and then the dry film is annealed for 30min in the air at 550 ℃ to obtain the crystalline BGSFMC film.
Step 6: cooling the crystalline BGSFMC film, and placing the film on the BGSFMC filmRepeating the step 5 to reach the preset thickness to obtain BGSFMC/CM0.1FO composite membranes.
Example 2
Step 1: cleaning the FTO/glass substrate respectively with liquid detergent, acetone and absolute ethyl alcohol, and sealing in absolute ethyl alcohol for later use;
step 2: dissolving cobalt nitrate, manganese acetate and ferric nitrate serving as raw materials in ethylene glycol monomethyl ether according to a molar ratio of 0.7:0.3:2(x is 0.3), stirring for 30min, adding acetic anhydride, and stirring for 90min to obtain a stable bottom layer membrane precursor solution with the total metal ion concentration of 0.2 mol/L; wherein the volume ratio of the ethylene glycol monomethyl ether to the acetic anhydride is 3: 1;
and step 3: washing FTO/glass substrate with deionized water, and washing with N2Blow-drying, irradiating the clean FTO/glass substrate for 40min by using an ultraviolet light irradiation instrument to ensure that the surface of the FTO/glass substrate reaches atomic cleanliness, then spin-coating the precursor solution on the FTO/glass substrate at the spin-coating rotation speed of 4000r/min for spin-coating for 10s to obtain a wet film, baking the wet film at 195 ℃ for 10min to obtain a dry film, and annealing in the air at 660 ℃ for 40min to obtain the crystalline Co/glass substrate0.7Mn0.3Fe2O4A film;
and 4, step 4: dissolving bismuth nitrate, gadolinium nitrate, strontium nitrate, ferric nitrate, manganese acetate and cobalt nitrate (the excessive amount of bismuth nitrate is 5%) in ethylene glycol monomethyl ether according to the molar ratio of 0.92:0.09:0.03:0.94:0.04:0.02, adding acetic anhydride after uniformly stirring, and continuously and uniformly stirring to obtain a stable upper layer membrane precursor solution with the total metal ion concentration of 0.3 mol/L; wherein the volume ratio of the ethylene glycol monomethyl ether to the acetic anhydride is 3: 1;
and 5: coating step 3 with crystalline Co0.7Mn0.3Fe2O4Irradiating the FTO/glass substrate with ultraviolet irradiation instrument for 40min to make the surface of the substrate reach atom cleanliness, and spin-coating the precursor solution of the upper layer film on the substrate covered with crystalline Co0.7Mn0.3Fe2O4On the FTO/glass substrate of the film, the spin coating speed is 4000r/min, the spin coating time is 10s, a wet film is obtained, the wet film is baked for 10min at 195 ℃ to obtain a dry film, and then the dry film is annealed for 30min in the air at 550 DEG CAnd obtaining the crystalline BGSFMC film.
Step 6: after the crystalline BGSFMC film is cooled, repeating the step 5 on the BGSFMC film to reach the preset thickness, and obtaining BGSFMC/CM0.3FO composite membranes.
Example 3
Step 1: cleaning the FTO/glass substrate respectively with liquid detergent, acetone and absolute ethyl alcohol, and sealing in absolute ethyl alcohol for later use;
step 2: dissolving cobalt nitrate, manganese acetate and ferric nitrate serving as raw materials in ethylene glycol monomethyl ether according to a molar ratio of 0.5:0.5:2(x is 0.5), stirring for 30min, adding acetic anhydride, and stirring for 90min to obtain a stable bottom layer membrane precursor solution with the total metal ion concentration of 0.2 mol/L; wherein the volume ratio of the ethylene glycol monomethyl ether to the acetic anhydride is 3: 1;
and step 3: washing FTO/glass substrate with deionized water, and washing with N2Blow-drying, irradiating the clean FTO/glass substrate for 40min by using an ultraviolet light irradiation instrument to ensure that the surface of the FTO/glass substrate reaches atomic cleanliness, then spin-coating the precursor solution on the FTO/glass substrate at the spin-coating rotation speed of 4000r/min for spin-coating for 10s to obtain a wet film, baking the wet film at 195 ℃ for 10min to obtain a dry film, and annealing in the air at 660 ℃ for 40min to obtain the crystalline Co/glass substrate0.5Mn0.5Fe2O4A film;
and 4, step 4: dissolving bismuth nitrate, gadolinium nitrate, strontium nitrate, ferric nitrate, manganese acetate and cobalt nitrate (the excessive amount of bismuth nitrate is 5%) in ethylene glycol monomethyl ether according to the molar ratio of 0.92:0.09:0.03:0.94:0.04:0.02, adding acetic anhydride after uniformly stirring, and continuously and uniformly stirring to obtain a stable upper layer membrane precursor solution with the total metal ion concentration of 0.3 mol/L; wherein the volume ratio of the ethylene glycol monomethyl ether to the acetic anhydride is 3: 1;
and 5: coating step 3 with crystalline Co0.5Mn0.5Fe2O4Irradiating the FTO/glass substrate with ultraviolet irradiation instrument for 40min to make the surface of the substrate reach atom cleanliness, and spin-coating the precursor solution of the upper layer film on the substrate covered with crystalline Co0.5Mn0.5Fe2O4The spin speed of the thin film FTO/glass substrate is 4000r/min, homogenizing for 10s to obtain wet film, baking the wet film at 195 deg.C for 10min to obtain dry film, and annealing at 550 deg.C in air for 30min to obtain crystalline BGSFMC film.
Step 6: after the crystalline BGSFMC film is cooled, repeating the step 5 on the BGSFMC film to reach the preset thickness, and obtaining BGSFMC/CM0.5FO composite membranes.
Example 4
Step 1: cleaning the FTO/glass substrate respectively with liquid detergent, acetone and absolute ethyl alcohol, and sealing in absolute ethyl alcohol for later use;
step 2: dissolving cobalt nitrate, manganese acetate and ferric nitrate serving as raw materials in ethylene glycol monomethyl ether according to a molar ratio of 0.3:0.7:2(x is 0.7), stirring for 30min, adding acetic anhydride, and stirring for 90min to obtain a stable bottom layer membrane precursor solution with the total metal ion concentration of 0.2 mol/L; wherein the volume ratio of the ethylene glycol monomethyl ether to the acetic anhydride is 3: 1;
and step 3: washing FTO/glass substrate with deionized water, and washing with N2Blow-drying, irradiating the clean FTO/glass substrate for 40min by using an ultraviolet light irradiation instrument to ensure that the surface of the FTO/glass substrate reaches atomic cleanliness, then spin-coating the precursor solution on the FTO/glass substrate at the spin-coating rotation speed of 4000r/min for spin-coating for 10s to obtain a wet film, baking the wet film at 195 ℃ for 10min to obtain a dry film, and annealing in the air at 660 ℃ for 40min to obtain the crystalline Co/glass substrate0.3Mn0.7Fe2O4A film;
and 4, step 4: dissolving bismuth nitrate, gadolinium nitrate, strontium nitrate, ferric nitrate, manganese acetate and cobalt nitrate (the excessive amount of bismuth nitrate is 5%) in ethylene glycol monomethyl ether according to the molar ratio of 0.92:0.09:0.03:0.94:0.04:0.02, adding acetic anhydride after uniformly stirring, and continuously and uniformly stirring to obtain a stable upper layer membrane precursor solution with the total metal ion concentration of 0.3 mol/L; wherein the volume ratio of the ethylene glycol monomethyl ether to the acetic anhydride is 3: 1;
and 5: coating step 3 with crystalline Co0.3Mn0.7Fe2O4Irradiating the FTO/glass substrate with ultraviolet irradiation instrument for 40min to make the surface of the substrate reach atom cleanliness, and spin-coating the upper layer film precursor solution on the coating filmCovered with crystalline Co0.3Mn07Fe2O4And (3) on the FTO/glass substrate of the film, the spin coating speed is 4000r/min, the spin coating time is 10s, a wet film is obtained, the wet film is baked for 10min at 195 ℃ to obtain a dry film, and then the dry film is annealed for 30min in the air at 550 ℃ to obtain the crystalline BGSFMC film.
Step 6: after the crystalline BGSFMC film is cooled, repeating the step 5 on the BGSFMC film to reach the preset thickness, and obtaining BGSFMC/CM0.7FO composite membranes.
Example 5
Step 1: cleaning the FTO/glass substrate respectively with liquid detergent, acetone and absolute ethyl alcohol, and sealing in absolute ethyl alcohol for later use;
step 2: dissolving cobalt nitrate, manganese acetate and ferric nitrate serving as raw materials in ethylene glycol monomethyl ether according to a molar ratio of 0.3:0.7:2(x is 0.7), stirring for 30min, adding acetic anhydride, and stirring for 90min to obtain a stable bottom layer membrane precursor solution with the total metal ion concentration of 0.25 mol/L; wherein the volume ratio of the ethylene glycol monomethyl ether to the acetic anhydride is 2.5: 1;
and step 3: washing FTO/glass substrate with deionized water, and washing with N2Blow-drying, irradiating the clean FTO/glass substrate for 40min by using an ultraviolet light irradiation instrument to ensure that the surface of the FTO/glass substrate reaches atomic cleanliness, then spin-coating the precursor solution on the FTO/glass substrate at a spin-coating rotation speed of 3500r/min for spin-coating for 12s to obtain a wet film, baking the wet film at 190 ℃ for 8min to obtain a dry film, and annealing at 680 ℃ for 35min in air to obtain the crystalline Co/glass substrate0.3Mn0.7Fe2O4A film;
and 4, step 4: dissolving bismuth nitrate, gadolinium nitrate, strontium nitrate, ferric nitrate, manganese acetate and cobalt nitrate (the excessive amount of bismuth nitrate is 5%) in ethylene glycol monomethyl ether according to the molar ratio of 0.92:0.09:0.03:0.94:0.04:0.02, adding acetic anhydride after uniformly stirring, and continuously and uniformly stirring to obtain a stable upper layer membrane precursor solution with the total metal ion concentration of 0.28 mol/L; wherein the volume ratio of the ethylene glycol monomethyl ether to the acetic anhydride is 2.5: 1;
and 5: coating step 3 with crystalline Co0.3Mn0.7Fe2O4Thin film FTO/glass substrate re-use with UVIrradiating clean FTO/glass substrate with light irradiation instrument for 40min to make the surface of the substrate reach atom cleanliness, and spin-coating the upper layer film precursor solution on the substrate covered with crystalline Co0.3Mn07Fe2O4And (3) on the FTO/glass substrate of the film, the glue homogenizing rotating speed is 3500r/min, the glue homogenizing time is 12s, a wet film is obtained, the wet film is baked for 8min at 190 ℃ to obtain a dry film, and the dry film is annealed for 25min in the air at 560 ℃ to obtain the crystalline BGSFMC film.
Step 6: after the crystalline BGSFMC film is cooled, repeating the step 5 on the BGSFMC film to reach the preset thickness, and obtaining BGSFMC/CM0.7FO composite membranes.
Example 6
Step 1: cleaning the FTO/glass substrate respectively with liquid detergent, acetone and absolute ethyl alcohol, and sealing in absolute ethyl alcohol for later use;
step 2: dissolving cobalt nitrate, manganese acetate and ferric nitrate serving as raw materials in ethylene glycol monomethyl ether according to a molar ratio of 0.3:0.7:2(x is 0.7), stirring for 30min, adding acetic anhydride, and stirring for 90min to obtain a stable bottom layer membrane precursor solution with the total metal ion concentration of 0.3 mol/L; wherein the volume ratio of the ethylene glycol monomethyl ether to the acetic anhydride is 2.8: 1;
and step 3: washing FTO/glass substrate with deionized water, and washing with N2Blow-drying, irradiating the clean FTO/glass substrate with an ultraviolet light irradiation instrument for 40min to ensure that the surface of the FTO/glass substrate reaches atomic cleanliness, then spin-coating the precursor solution on the FTO/glass substrate at a spin-coating rotation speed of 3800r/min for 14s to obtain a wet film, baking the wet film at 192 ℃ for 9min to obtain a dry film, and annealing at 700 ℃ for 38min in air to obtain the crystalline Co/glass substrate0.3Mn0.7Fe2O4A film;
and 4, step 4: dissolving bismuth nitrate, gadolinium nitrate, strontium nitrate, ferric nitrate, manganese acetate and cobalt nitrate (the excessive amount of bismuth nitrate is 5%) in ethylene glycol monomethyl ether according to the molar ratio of 0.92:0.09:0.03:0.94:0.04:0.02, adding acetic anhydride after uniformly stirring, and continuously and uniformly stirring to obtain a stable upper layer membrane precursor solution with the total metal ion concentration of 0.25 mol/L; wherein the volume ratio of the ethylene glycol monomethyl ether to the acetic anhydride is 2.8: 1;
step (ii) of5: coating step 3 with crystalline Co0.3Mn0.7Fe2O4Irradiating the FTO/glass substrate with ultraviolet irradiation instrument for 40min to make the surface of the substrate reach atom cleanliness, and spin-coating the precursor solution of the upper layer film on the substrate covered with crystalline Co0.3Mn07Fe2O4And (3) on the FTO/glass substrate of the film, the glue homogenizing rotating speed is 4000r/min, the glue homogenizing time is 14s, a wet film is obtained, the wet film is baked for 9min at 192 ℃ to obtain a dry film, and then annealing is carried out in the air for 28min at 570 ℃ to obtain the crystalline BGSFMC film.
Step 6: after the crystalline BGSFMC film is cooled, repeating the step 5 on the BGSFMC film to reach the preset thickness, and obtaining BGSFMC/CM0.7FO composite membranes.
Example 7
Step 1: cleaning the FTO/glass substrate respectively with liquid detergent, acetone and absolute ethyl alcohol, and sealing in absolute ethyl alcohol for later use;
step 2: dissolving cobalt nitrate, manganese acetate and ferric nitrate serving as raw materials in ethylene glycol monomethyl ether according to a molar ratio of 0.3:0.7:2(x is 0.7), stirring for 30min, adding acetic anhydride, and stirring for 90min to obtain a stable bottom layer membrane precursor solution with the total metal ion concentration of 0.35 mol/L; wherein the volume ratio of the ethylene glycol monomethyl ether to the acetic anhydride is 3: 1;
and step 3: washing FTO/glass substrate with deionized water, and washing with N2Drying, irradiating the clean FTO/glass substrate for 40min by using an ultraviolet light irradiation instrument to ensure that the surface of the FTO/glass substrate reaches atomic cleanliness, then spin-coating the precursor solution on the FTO/glass substrate at the spin-coating rotation speed of 4000r/min for spin-coating for 16s to obtain a wet film, baking the wet film at 190 ℃ for 10min to obtain a dry film, and annealing in the air at 710 ℃ for 40min to obtain the crystalline Co/glass substrate0.3Mn0.7Fe2O4A film;
and 4, step 4: dissolving bismuth nitrate, gadolinium nitrate, strontium nitrate, ferric nitrate, manganese acetate and cobalt nitrate (the excessive amount of bismuth nitrate is 5%) in ethylene glycol monomethyl ether according to the molar ratio of 0.92:0.09:0.03:0.94:0.04:0.02, adding acetic anhydride after uniformly stirring, and continuously and uniformly stirring to obtain a stable upper layer membrane precursor solution with the total metal ion concentration of 0.22 mol/L; wherein the volume ratio of the ethylene glycol monomethyl ether to the acetic anhydride is 3.2: 1;
and 5: coating step 3 with crystalline Co0.3Mn0.7Fe2O4Irradiating the FTO/glass substrate with ultraviolet irradiation instrument for 42min to make the surface of the substrate reach atom cleanliness, and spin-coating the precursor solution of the upper layer film on the substrate covered with crystalline Co0.3Mn07Fe2O4And (3) on the FTO/glass substrate of the film, the glue homogenizing rotating speed is 3800r/min, the glue homogenizing time is 16s, a wet film is obtained, the wet film is baked for 10min at 190 ℃ to obtain a dry film, and then the dry film is annealed for 32min in the air at 580 ℃ to obtain the crystalline BGSFMC film.
Step 6: after the crystalline BGSFMC film is cooled, repeating the step 5 on the BGSFMC film to reach the preset thickness, and obtaining BGSFMC/CM0.7FO composite membranes.
Example 8
Step 1: cleaning the FTO/glass substrate respectively with liquid detergent, acetone and absolute ethyl alcohol, and sealing in absolute ethyl alcohol for later use;
step 2: dissolving cobalt nitrate, manganese acetate and ferric nitrate serving as raw materials in ethylene glycol monomethyl ether according to a molar ratio of 0.3:0.7:2(x is 0.7), stirring for 30min, adding acetic anhydride, and stirring for 90min to obtain a stable bottom layer membrane precursor solution with the total metal ion concentration of 0.4 mol/L; wherein the volume ratio of the ethylene glycol monomethyl ether to the acetic anhydride is 3.5: 1;
and step 3: washing FTO/glass substrate with deionized water, and washing with N2Blow-drying, irradiating the clean FTO/glass substrate for 40min by using an ultraviolet light irradiation instrument to ensure that the surface of the FTO/glass substrate reaches atomic cleanliness, then spin-coating the precursor solution on the FTO/glass substrate at the spin-coating rotation speed of 4000r/min for 15s to obtain a wet film, baking the wet film at 195 ℃ for 10min to obtain a dry film, and annealing at 660 ℃ for 45min in the air to obtain the crystalline Co/glass substrate0.3Mn0.7Fe2O4A film;
and 4, step 4: dissolving bismuth nitrate, gadolinium nitrate, strontium nitrate, ferric nitrate, manganese acetate and cobalt nitrate (the excessive amount of bismuth nitrate is 5%) in ethylene glycol monomethyl ether according to the molar ratio of 0.92:0.09:0.03:0.94:0.04:0.02, adding acetic anhydride after uniformly stirring, and continuously and uniformly stirring to obtain a stable upper layer membrane precursor solution with the total metal ion concentration of 0.2 mol/L; wherein the volume ratio of the ethylene glycol monomethyl ether to the acetic anhydride is 3.5: 1;
and 5: coating step 3 with crystalline Co0.3Mn0.7Fe2O4Irradiating the FTO/glass substrate with ultraviolet irradiation instrument for 40min to make the surface of the substrate reach atom cleanliness, and spin-coating the precursor solution of the upper layer film on the substrate covered with crystalline Co0.3Mn07Fe2O4And (3) on the FTO/glass substrate of the film, the glue homogenizing rotating speed is 4000r/min, the glue homogenizing time is 15s, a wet film is obtained, the wet film is baked for 10min at 195 ℃ to obtain a dry film, and then annealing is carried out in the air for 35min at 600 ℃ to obtain the crystalline BGSFMC film.
Step 6: after the crystalline BGSFMC film is cooled, repeating the step 5 on the BGSFMC film to reach the preset thickness, and obtaining BGSFMC/CM0.7FO composite membranes.
Comparative example 1
Step 1: cleaning the FTO/glass substrate respectively with liquid detergent, acetone and absolute ethyl alcohol, and sealing in absolute ethyl alcohol for later use;
step 2: dissolving cobalt nitrate and ferric nitrate serving as raw materials in ethylene glycol monomethyl ether according to a molar ratio of 1:2(x is 0), stirring for 30min, adding acetic anhydride, and stirring for 90min to obtain a stable bottom layer membrane precursor solution with the total metal ion concentration of 0.2 mol/L; wherein the volume ratio of the ethylene glycol monomethyl ether to the acetic anhydride is 3: 1;
and step 3: washing FTO/glass substrate with deionized water, and washing with N2Blow-drying, irradiating the clean FTO/glass substrate for 40min by using an ultraviolet light irradiation instrument to ensure that the surface of the FTO/glass substrate reaches atomic cleanliness, then spin-coating the precursor solution of the bottom layer film on the FTO/glass substrate at the spin-coating speed of 4000r/min for 10s to obtain a wet film, baking the wet film at 195 ℃ for 10min to obtain a dry film, and annealing in the air at 660 ℃ for 40min to obtain the crystalline CoFe2O4A film;
and 4, step 4: dissolving bismuth nitrate, gadolinium nitrate, strontium nitrate, ferric nitrate, manganese acetate and cobalt nitrate (the excessive amount of bismuth nitrate is 5%) in ethylene glycol monomethyl ether according to the molar ratio of 0.92:0.09:0.03:0.94:0.04:0.02, adding acetic anhydride after uniformly stirring, and continuously and uniformly stirring to obtain a stable upper layer membrane precursor solution with the total metal ion concentration of 0.3 mol/L; wherein the volume ratio of the ethylene glycol monomethyl ether to the acetic anhydride is 3: 1;
and 5: step 3 was covered with crystalline CoFe2O4Irradiating the FTO/glass substrate with ultraviolet irradiation instrument for 40min to make the surface of the substrate reach atom cleanliness, and spin-coating the precursor solution on the substrate covered with crystalline CoFe2O4And (3) on the FTO/glass substrate of the film, the spin coating speed is 4000r/min, the spin coating time is 10s, a wet film is obtained, the wet film is baked for 10min at 195 ℃ to obtain a dry film, and then the dry film is annealed for 30min in the air at 550 ℃ to obtain the crystalline BGSFMC film.
Step 6: and (5) after the crystalline BGSFMC film is cooled, repeating the step (5) on the BGSFMC film to reach the preset thickness, and thus obtaining the BGSFMC/CFO composite film.
Determination of BGSFMC/C with resistance switch effect by XRD1-xMxPhase composition structure of FO composite membranes. Measurement of BGSFMC/C by SEM1-xMxMicrostructure of FO composite films. Testing BGSFMC/C with Agilent E4980A precision LCR meter1-xMxDielectric properties of FO composite films. Testing of BGSFMC/C with Agilent B29001-xMxLeakage current characteristics of FO composite membranes. Testing BGSFMC/C with radial Multiferroic ferroelectric analyzer1-xMxFerroelectric properties of FO composite films.
FIG. 1 is an XRD pattern of a Mn doped controlled resistance switching effect composite film obtained in examples 1-4 of the present invention and an XRD pattern of comparative example 1, from which Bi prepared by a sol-gel method is shown0.88Gd0.09Sr0.03Fe0.94Mn0.04Co0.02O3/Co1-xMnxFe2O4The upper layer of the film is a BGSFMC film with a polycrystalline twisted perovskite structure and a space group of R3 c; the lower layer is C with a cubic inverse spinel structure and a space group Fd3m1-xMxFO thin filmNo impurities were present.
FIG. 2 shows Bi prepared in example 2 of the present invention0.88Gd0.09Sr0.03Fe0.94Mn0.04Co0.02O3/Co0.7Mn0.3Fe2O4The composite film has a remanent polarization value of 90.5-135 mu C/cm under an applied voltage of 20-35V2The rectangular degree R of the symmetrical rectangular hysteresis loopsqThe composite film has stable ferroelectric properties against voltage changes, as defined by 1.07 to 1.12.
FIG. 3 shows Bi prepared in example 4 of the present invention0.88Gd0.09Sr0.03Fe0.94Mn0.04Co0.02O3/Co0.3Mn0.7Fe2O4The leakage current line graph of the composite film under the applied electric field shows that the HRS/LRS ratio of the high resistance state to the low resistance state is 1.9, namely the composite film still has the resistance switching effect after being compounded with the magnetic film.
FIG. 4 shows Bi prepared in example 2 of the present invention0.88Gd0.09Sr0.03Fe0.94Mn0.04Co0.02O3/Co0.7Mn0.3Fe2O4As can be seen from the hysteresis curves of the composite films and that of comparative example 1, the saturation magnetization value was 43emu/cm3The remanent magnetization value is 28.5emu/cm3And has better ferromagnetism.
The above-described details are further intended to describe the present invention in connection with the particular preferred embodiments thereof, and it is not intended to limit the invention to all or the only embodiments disclosed, and all equivalents and modifications which may occur to those skilled in the art upon reading the present specification are intended to be encompassed by the present claims.
Claims (6)
1. A preparation method of a Mn-doped composite film for regulating and controlling a resistance switching effect is characterized in that the Mn-doped composite film for regulating and controlling the resistance switching effect comprises an upper layer film and a lower layer film which are compounded together; the upper film has a chemical formula of Bi0.88Gd0.09Sr0.03Fe0.94Mn0.04Co0.02O3The perovskite structure is a polycrystalline twisted perovskite structure, and the space group is R3 c; the underlayer film has the chemical formula of Co1- xMnxFe2O4The material is of a cubic inverse spinel structure, and the space group is Fd3m, wherein x is 0.7, and the ratio of high-low resistance state HRS/LRS is 1.9;
comprises the following steps of (a) carrying out,
step 1, dissolving cobalt nitrate, manganese acetate and ferric nitrate in ethylene glycol monomethyl ether, adding acetic anhydride after uniformly stirring, and continuously uniformly stirring to obtain a bottom layer membrane precursor solution;
step 2, spin-coating the bottom layer film precursor solution on an FTO/glass substrate to obtain a wet film, baking the wet film at 190-195 ℃ after spin-coating to obtain a dry film, and annealing in air at 660-710 ℃ to obtain crystalline Co1-xMnxFe2O4A film;
step 3, mixing the crystalline Co1-xMnxFe2O4Cooling the film, and repeating the step 2 until the preset thickness is reached to obtain a bottom layer film;
step 4, dissolving bismuth nitrate, gadolinium nitrate, strontium nitrate, ferric nitrate, manganese acetate and cobalt nitrate in ethylene glycol monomethyl ether, adding acetic anhydride after uniformly stirring, and continuously uniformly stirring to obtain an upper layer membrane precursor solution;
step 5, coating the upper layer film precursor solution on the lower layer film obtained in the step 3 to obtain a wet film, baking the wet film at 190-195 ℃ after spin coating to obtain a dry film, and annealing the dry film in air at 550-600 ℃ to obtain crystalline Bi0.88Gd0.09Sr0.03Fe0.94Mn0.04Co0.02O3A film;
step 6: bi to be crystallized0.88Gd0.09Sr0.03Fe0.94Mn0.04Co0.02O3After the film is cooled, Bi is added0.88Gd0.09Sr0.03Fe0.9 4Mn0.04Co0.02O3Repeating the step 5 on the film to reach the preset thickness, and obtaining the Mn-doped composite film for regulating the resistance switching effect;
the annealing time in the step 2 is 35-45 min;
the annealing time in the step 5 is 25-35 min.
2. The method for preparing a Mn-doped composite film with a resistance switching effect according to claim 1, wherein in the step 1, the total concentration of metal ions in the underlayer film precursor solution is 0.2-0.4 mol/L.
3. The method for preparing a Mn-doped composite film with a resistance switching effect according to claim 1, wherein in the step 4, the total concentration of metal ions in the upper film precursor solution is 0.2-0.3 mol/L.
4. The preparation method of the Mn-doped composite film with the resistance switching effect regulated and controlled according to claim 1, wherein the volume ratio of ethylene glycol monomethyl ether to acetic anhydride in the bottom layer film precursor solution to the upper layer film precursor solution is (2.5-3.5): 1.
5. The preparation method of the Mn-doped composite film with the resistance switching effect regulated and controlled according to claim 1, wherein in the step 2 and the step 5, the glue homogenizing rotating speed during glue homogenizing is 3500-4000 r/min, and the glue homogenizing time is 10-16 s.
6. The method for preparing the Mn-doped composite film with the resistance switching effect regulated and controlled according to claim 1, wherein in the step 2 and the step 5, the baking time after glue homogenizing is 8-10 min.
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| CN105837199A (en) * | 2016-03-31 | 2016-08-10 | 陕西科技大学 | Bi<0.96>Sr<0.04>Fe<0.98-x>Mn<x>Co<0.02>O<3> multiferroic film and preparation method thereof |
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