	US 11,658,310 B2
	High-performance cathode catalyst for metal-air battery and preparation method thereof
Xingmei Guo, Jiangsu (CN); Junhao Zhang, Jiangsu (CN); Wei Zhang, Jiangsu (CN); and Xiaohan Wan, Jiangsu (CN)
Assigned to JIANGSU UNIVERSITY OF SCIENCE AND TECHNOLOGY, Jiangsu (CN)
Appl. No. 17/638,188
Filed by JIANGSU UNIVERSITY OF SCIENCE AND TECHNOLOGY, Jiangsu (CN)
PCT Filed Jul. 6, 2021, PCT No. PCT/CN2021/104742 § 371(c)(1), (2) Date Feb. 25, 2022, PCT Pub. No. WO2022/095492, PCT Pub. Date May 12, 2022.
Claims priority of application No. 202011215077.2 (CN), filed on Nov. 4, 2020.
Prior Publication US 2022/0352526 A1, Nov. 3, 2022
Int. Cl. H01M 4/90 (2006.01); H01M 4/88 (2006.01); H01M 12/08 (2006.01); H01M 4/86 (2006.01)

CPC H01M 4/9083 (2013.01) [H01M 4/8817 (2013.01); H01M 4/8846 (2013.01); H01M 4/9016 (2013.01); H01M 12/08 (2013.01); H01M 2004/8689 (2013.01)]

9 Claims

1. A preparation method of the high-performance positive electrode catalyst for a metal-air battery, wherein the catalyst is composed of transition metal nitride-transition metal oxide heterogeneous particles and a mesoporous-structure carbon matrix; the heterogeneous particles are dispersed in the mesoporous-structure carbon matrix in a form of nanoparticles; the heterogeneous particles have a size of 20-80 nm, and are 10-50% based on a total mass of the catalyst; the heterogeneous particles consist of a nitride of a transition metal and an oxide of the transition metal, wherein the oxide of the transition metal is 10 to less than 100% based on a total mass of the heterogeneous particles, and the preparation method comprising the following steps:

(1) surface functionalized processing on mesoporous carbon, wherein

the mesoporous carbon is dispersed in a strong acid solution, and stirred for 0.5 h to 2 h, so that the strong acid solution is fully immersed in a mesoporous structure of the mesoporous carbon to obtain a dispersion; the dispersion is put into a reaction kettle, held at 100-200° C. for 2 h to 6 h, and then naturally cooled to room temperature; the mesoporous carbon treated with the strong acid solution is centrifugally separated out and centrifugally washed using water and ethanol to obtain a resulting product, and the resulting product is dried in vacuum to obtain surface-functionalized mesoporous carbon; and

(2) co-adsorption of transition metal ions Mⁿand transition metal ammonia complex ions M(NH₃)_mⁿ⁺ on the mesoporous carbon, wherein

the surface-functionalized mesoporous carbon obtained in step (1) is immersed in an aqueous solution of a transition metal M salt having a concentration of 1-10 mmol and stirred for 0.5 h to 4 h so that the transition metal ions Mⁿ⁺ are adsorbed on the mesoporous carbon; the mesoporous carbon adsorbing the transition metal ions Mⁿ⁺ is centrifugally washed using water, and then dispersed in water again; after that, ammonia water having a concentration of 25%-28% is added, and stirred for 0.5 h to 2 h so that some of the transition metal ions Mⁿ⁻ adsorbed on the mesoporous carbon contact the ammonia water and react to generate transition metal ammonia complex ions M(NH₃)_mⁿ⁺; then the mesoporous carbon contacted the ammonia water is centrifugally washed using water and ethanol respectively to obtain a resulting product; and the resulting product is dried in vacuum to obtain mesoporous carbon with Mⁿ⁺ and M(NH₃)_mⁿ⁺ adsorbed thereon, namely, M(NH₃)_mⁿ⁺&Mⁿ⁺/C; and

(3) heat treatment on the mesoporous carbon with Mⁿ⁺ and M(NH₃)_mⁿ⁺ adsorbed thereon to obtain a MN_x-MO_y/C composite, wherein

the M(NH₃)_mⁿ⁺&Mⁿ⁻/C obtained in step (2) is calcined in an inert atmosphere or a vacuum condition, to obtain a composite having transition metal nitride-transition metal oxide heterogeneous particles highly dispersed in the mesoporous carbon matrix, namely, MN_x-MO_y/C.