US 12,145,887 B2
Multiphase ceramic material with giant dielectric constant, and preparation method thereof
Xiuhua Cao, Guangdong (CN); Jianmei Liu, Canberra (AU); Dehong Chen, Canberra (AU); Haidong Ren, Guangdong (CN); Yun Liu, Canberra (AU); Terry James Frankcombe, Canberra (AU); Zhenxiao Fu, Guangdong (CN); and Shiwo Ta, Guangdong (CN)
Assigned to GUANGDONG FENGHUA ADVANCED TECHNOLOGY HOLDING CO., LTD., Zhaoqing (CN)
Appl. No. 17/296,259
Filed by GUANGDONG FENGHUA ADVANCED TECHNOLOGY HOLDING CO., LTD., Guangdong (CN)
PCT Filed Mar. 29, 2020, PCT No. PCT/CN2020/081953
§ 371(c)(1), (2) Date May 24, 2021,
PCT Pub. No. WO2021/184414, PCT Pub. Date Sep. 23, 2021.
Claims priority of application No. 202010205096.0 (CN), filed on Mar. 20, 2020.
Prior Publication US 2022/0127197 A1, Apr. 28, 2022
Int. Cl. C04B 35/462 (2006.01); C04B 35/622 (2006.01); C04B 35/626 (2006.01); C04B 35/64 (2006.01); H01B 3/12 (2006.01)
CPC C04B 35/462 (2013.01) [C04B 35/622 (2013.01); C04B 35/6261 (2013.01); C04B 35/6264 (2013.01); C04B 35/62655 (2013.01); C04B 35/62695 (2013.01); C04B 35/64 (2013.01); H01B 3/12 (2013.01); C04B 2235/3234 (2013.01); C04B 2235/6021 (2013.01); C04B 2235/604 (2013.01); C04B 2235/606 (2013.01); C04B 2235/612 (2013.01); C04B 2235/6562 (2013.01); C04B 2235/6567 (2013.01); C04B 2235/662 (2013.01); C04B 2235/762 (2013.01); C04B 2235/80 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A method of preparing a multiphase ceramic material with a dielectric constant of higher than 10,000, wherein the multiphase ceramic material has a general formula of AxBnxTi1−(n+1)xO2; wherein A is at least one selected from the group consisting of Nb, Ta, V, Mo, and Sb, B is at least one selected from the group consisting of In, Ga, Al, Co, Cr, Sc, Fe (III), and a trivalent rare-earth cation; n is a molar ratio of B to A, 1<n≤5, 0<x≤0.1;
wherein the method comprises steps of:
(1) weighing reactants, which comprise a titanium source, an A source, and a B source, according to the general formula of the multiphase ceramic material, AxBnxTi1−(n+1)xO2;
(2) ball-milling in a ball-milling tank and drying to obtain a homogeneous mixture powder;
(3) transferring the mixture powder into a mortar; pure water is added, and the weight of the pure water is 5%-10% of the weight of the mixture powder; mixing thoroughly;
transferring the mixture powder into a die, pressing at a pressure of at least 400 MPa to obtain a green pellet; placing the green pellet in a mortar; pulverizing and grinding the green pellet to obtain a preliminary powder;
(4) transferring the preliminary powder into a die; pressing at a pressure of at least 2 MPa, followed by sintering; sintering parameters comprise heating rate: 1.5° C./min-15° C./min, temperature: 1200° C.-1500° C., holding time: 1 h-24 h; after sintering, the product obtained is naturally cooled down to room temperature to obtain a dense ceramic pellet;
(5) polishing a surface of the dense ceramic pellet, followed by annealing; annealing parameters comprise heating rate: 1.5° C./min-15° C./min, temperature: 1000° C.-1200° C., holding time: 1 h-24 h; after annealing, the product obtained is naturally cooled down to room temperature to obtain the multiphase ceramic material with a dielectric constant of higher than 10,000.