Synthesis of High-Conductivity Entropy-Stabilized Nanometal Oxide

Example 1

Provided is a preparation method for an A-site high-entropy nanometer metal oxide (Gd_0.4Er_0.3La_0.4Nd_0.5Y_0.4)(Zr_0.7, Sn_0.8, V_0.5)O₇ with high conductivity, the method including the following steps.

• • (1) Gd(NO₃)₃, Er(NO₃)₃, La(NO₃)₃, Nd(NO₃)₃, Y(NO₃)₃, ZrOSO₄, SnC₁₄ and NH₄VO₃ were taken at a molar ratio of 0.4:0.3:0.4:0.5:0.4:0.7:0.8:0.5, added to a mixed solution of deionized water/absolute ethyl alcohol/tetrahydrofuran at a mass ratio of 0.3:3:0.5, and stirred for five minutes to obtain a mixed liquid I. The ratio of the total mass of Gd(NO₃)₃, Er(NO₃)₃, La(NO₃)₃, Nd(NO₃)₃, Y(NO₃)₃, ZrOSO₄, SnC₁₄ and NH₄VO₃ to that of the mixed solution of deionized water/absolute ethyl alcohol/tetrahydrofuran (0.3:3:0.5) is 12.6%.
  • (2) Para-phenylene diamine, hydrogenated tallowamine, sorbitol and carbamyl ethyl acetate at a mass ratio of 1:0.2:7:0.01 were taken, added to propyl alcohol, and stirred for one hour to obtain a mixed liquid II. The ratio of the total mass of the para-phenylene diamine, the hydrogenated tallowamine, the sorbitol and the carbamyl ethyl acetate to that of the propyl alcohol is 7.5%;
  • (3) The mixed liquid I obtained in step (1) was heated to 50° C., and the mixed liquid II obtained in step (2) was dripped at the speed of one drop per second, into the mixed liquid I obtained in step (1) with stirring and ultrasound, and heated to the temperature of 85° C. after the dripping is completed and the temperature was maintained for three hours while stopping stirring, and the temperature was decreased to the room temperature, so as to obtain a mixed liquid III. The mass ratio of the mixed liquid I to the mixed liquid II is 10:4.
  • (4) The mixed liquid III was added to an electrolytic cell with using a platinum electrode as an electrode and applying a voltage of 3 V to two ends of the electrode, and reacting for 13 minutes, to obtain a mixed liquid IV.
  • (5) The mixed liquid IV obtained in step (4) was heated with stirring, another mixed liquid II was taken and dripped into the mixed liquid IV obtained in step (4) at the speed of one drop per second. The mass ratio of the mixed liquid II to the mixed liquid IV is 1.05:1.25; and after the dripping is completed, the temperature was decreased to the room temperature under stirring, so as to obtain a mixed liquid V.
  • (6) A high-speed shearing treatment was performed on the mixed liquid V obtained in step (5) by using a high-speed shear mulser at the speed of 20000 revolutions per minute for one hour, so as to obtain a mixed liquid VI.
  • (7) Lyophilization treatment was performed on the mixed liquid VI to obtain a mixture I;
  • (8) The mixture I obtained in step (7) and absolute ethyl alcohol were mixed at a mass ratio of 1:2 and uniformly stirred, and were sealed at a temperature of 210° C. for performing solvent thermal treatment for 18 hours. The reaction was cooled to the room temperature, the obtained powder was collected by centrifugation, washed with deionized water and absolute ethyl alcohol eight times respectively, and dried to obtain a powder I.
  • (9) The powder I obtained in step (8) and ammonium persulfate was uniformly mixed at a mass ratio of 10:1, and sealed and heated to 165° C. The temperature was maintained for 13 hours. The reaction was cooled to the room temperature, the obtained mixed powder was washed with deionized water ten times, and dried to obtain a powder II.
  • (10) The powder II obtained in step (4) was placed into a crucible, heated to a temperature of 1500° C. at a speed of 3° C. per minute. The temperature was maintained for 7 hours. The reaction was cooled to the room temperature, to obtain an A-site high-entropy nanometer metal oxide (Gd_0.4Er_0.3La_0.4Nd_0.5Y_0.4)(Zr_0.7, Sn_0.8, V_0.5)O₇ with high conductivity.

As observed via an electron microscope, the obtained A-site high-entropy nanometer metal oxide with high conductivity is a powder, and has microstructure of a square namometer sheet with a side length of about 4 nm and a thickness of about 1 nm.

The product powder was taken and compressed by using a powder sheeter at a pressure of 550 MPa into a sheet. Conductivity of the sheet is measured by using the four-probe method, and the conductivity of the product is 2.1×10⁸ S/m.

A commercially available ITO (indium tin oxide) powder is taken and compressed by using a powder sheeter at a pressure of 550 MPa into a sheet, and the conductivity of the sheet is measured by using the four-probe method.

As measured, the conductivity of the commercially available ITO (indium tin oxide) is 1.6×10⁶ S/m.