Method for forming rare earth-substitute nanocomposite

Patent metadata

Field	Value
Publication number	US-12183494-B2
Application number	US-202418791804-A
Country	US
Kind code	B2
Filing date	Aug 1, 2024
Priority date	May 7, 2021
Publication date	Dec 31, 2024
Grant date	Dec 31, 2024

Abstract

A magnetoelectric multiferroic nanocomposite. The nanocomposite comprises a ferroelectric perovskite oxide and a rare-earth substituted mixed ternary transition metal ferrite of the formula A1−xBxRyFe2−yO4. The nanocomposite has a high dielectric constant, low dielectric loss, both stable over a wide frequency range. These properties may make the nanocomposite desirable for applications in microelectronic devices, sensors and antennas.

First claim

The invention claimed is:

1. A method of forming a nanocomposite, comprising:
mixing ferroelectric perovskite oxide particles and rare-earth substituted mixed ternary transition metal ferrite particles to form a particle mixture, wherein the mixing includes combining a solution of Thulium oxide with a solution of transition metal nitrate salts to form the perovskite oxide particles and the rare-earth substituted mixed ternary transition metal ferrite particles;
milling the particle mixture to form a precursor powder;
pressing the precursor powder to form a pellet; and
sintering the pellet to form the nanocomposite;
wherein the rare-earth substituted mixed ternary transition metal ferrite particles are of formula
A 1−x B x R y Fe 2−y O 4 ,
wherein A and B represent different transition metals;
0<x<1;
R is Thulium;
0<y<0.2; and

the rare-earth substituted mixed ternary transition metal ferrite particles are superparamagnetic at 0 to 50° C.

2. The method of claim 1 , wherein the ferroelectric perovskite oxide particles are lead-free BaTiO 3 .

3. The method of claim 1 , wherein the ferroelectric perovskite oxide particles have a mean particle size of less than 1000 nm.

4. The method of claim 1 , wherein A is cobalt.

5. The method of claim 1 , wherein B is zinc.

6. The method of claim 1 , wherein 0.1≤x<0.5.

7. The method of claim 1 , wherein the rare-earth substituted mixed ternary transition metal ferrite particles are substantially free of nickel.

8. The method of claim 1 , wherein R is thulium.

9. The method of claim 1 , wherein 0.001≤y≤0.1.

10. The method of claim 1 , wherein the rare-earth substituted mixed ternary transition metal ferrite particles have a mean particle size of 10 nm to 5 μm.

11. The method of claim 1 , wherein a molar ratio of the rare-earth substituted mixed ternary transition metal ferrite particles to the ferroelectric perovskite oxide particles is 0.05:1 to 0.5:1.

12. The method of claim 1 , wherein the nanocomposite has a dielectric constant (ε′) of 10 to 15 for frequencies of 10 0 to 10 6 Hz at 0 to 140° C.

13. The method of claim 1 , wherein the nanocomposite has a dielectric loss tangent of 0 to 0.1 for frequencies of 10 0 to 10 6 Hz at 0 to 140° C.

14. The method of claim 1 , wherein the nanocomposite has a band gap of 1.40 to 2.5 eV.

15. The method of claim 1 , wherein the nanocomposite has a saturation magnetization of 0.1 to 20 emu/g at 0 to 50° C. and a magnetic coercivity of 10 to 2000 Oe at 0 to 50° C.

16. A method of forming a nanocomposite, comprising:
mixing ferroelectric perovskite oxide particles and rare-earth substituted mixed ternary transition metal ferrite particles to form a particle mixture, wherein the mixing includes combining a solution of a rare earth oxide with a solution of transition metal nitrate salts to form the perovskite oxide particles and the rare-earth substituted mixed ternary transition metal ferrite particles;
milling the particle mixture to form a precursor powder;
pressing the precursor powder to form a pellet; and
sintering the pellet to form the nanocomposite;
wherein the rare-earth substituted mixed ternary transition metal ferrite particles are of formula
A 1−x B x R y Fe 2−y O 4 ,

wherein A and B represent different transition metals:
0<x<1;
R is a rare-earth element;
0<y<0.2; and
the rare-earth substituted mixed ternary transition metal ferrite particles are superparamagnetic at 0 to 50° C.,
wherein the pressing is performed at 900 to 1100 MPa.

17. The method of claim 1 , wherein the sintering is performed at 850 to 1350° C. for 1 to 6 hours.

18. A method of forming a nanocomposite, comprising:
mixing ferroelectric perovskite oxide particles and rare-earth substituted mixed ternary transition metal ferrite particles to form a particle mixture, wherein the mixing includes combining a solution of a rare earth oxide with a solution of transition metal nitrate salts to form the perovskite oxide particles and the rare-earth substituted mixed ternary transition metal ferrite particles;
milling the particle mixture to form a precursor powder;
pressing the precursor powder to form a pellet; and
sintering the pellet to form the nanocomposite;
wherein the rare-earth substituted mixed ternary transition metal ferrite particles are of formula
A 1−x B x R y Fe 2−y O 4 ,

wherein A and B represent different transition metals:
0<x<1;
R is a rare-earth element;
0<y<0.2; and
the rare-earth substituted mixed ternary transition metal ferrite particles are superparamagnetic at 0 to 50° C.,
wherein the rare-earth substituted mixed ternary transition metal ferrite particles are prepared by:
mixing a cobalt (II) source, a zinc (II) source, an iron (III) source, and a thulium source in a solvent to form a precursor solution;
adding a base to the precursor solution to form a reaction mixture having a pH of 11 to 12;
ultrasonically treating the reaction mixture at a frequency of 18 to 25 kHz and a power of 50 to 100 W to form a precipitate; and
drying the precipitate to form the rare-earth substituted mixed ternary transition metal ferrite particles.

19. The method of claim 18 , wherein:
the cobalt (II) source is cobalt nitrate;
the zinc (II) source is zinc nitrate;
the iron (III) source is iron nitrate;
the thulium source is thulium oxide;
the base is sodium hydroxide; and
the ultrasonic treatment is performed for 30 to 120 minutes.

Assignees

• Univ Imam Abdulrahman Bin Faisal

Inventors

• Slimani Yassine
• Almessiere Munirah Abdullah
• Baykal Abdulhadi

Classifications

• H01F7/06

  Electromagnets; Actuators including electromagnets {(electric coils H01F5/00; devices for holding workpieces using electric force B23Q3/15; load-engaging elements for lifting articles electromagnetically B66C1/06; electromagnetic couplings F16D27/00; magnetic brakes F16D63/002; electromagnetically operated valves F16K11/24, F16K31/00; analysing materials by magnetic means G01N27/72, G01N27/80; electromagnets for winding mechanical clocks G04C1/02; electromagnetic relays H01H51/00; windings for salient poles of dynamo-electric machines H02K3/18; electromagnets for telegraphic communication H04L; for arc lamps H05B31/28)} · CPC title

• B82Y25/00

  Nanomagnetism, e.g. magnetoimpedance, anisotropic magnetoresistance, giant magnetoresistance or tunneling magnetoresistance · CPC title

• B82Y40/00

  Manufacture or treatment of nanostructures · CPC title

• H01F1/342 Primary

  Oxides (H01F1/36 and H01F1/38 take precedence) · CPC title