New nanowire catalysts are expected to reduce fuel cell prices substantially.

06 December 2018, 08:11 source: Science and Technology Daily
 
Original title: new nanowire catalyst is expected to reduce fuel cell prices substantially.

The reporter learned from University of Science & Technology China that Professor Zeng Jie, Professor of the National Research Center for microscale Material Science in Hefei, worked with Professor Huang Hongwen of Hunan University to develop a cathode catalyst for proton exchange membrane fuel cell (PEMFC) with excellent catalytic activity and stability. The results were published in the Journal of the American Chemical Society.

Proton exchange membrane fuel cell (PEMFC) has the advantages of zero emission, high energy efficiency and adjustable power. It is the most ideal driving power for electric vehicles in the future. However, the kinetics of cathode end oxygen reduction of proton exchange membrane fuel cells is very slow. It is necessary to use a large number of noble metal platinum nanomaterials as electrode catalysts to maintain the efficient operation of batteries, which makes the cost of proton exchange membrane fuel cell very high, and restricts its large-scale commercial application.

In PT based catalysts, improving the mass activity and catalytic stability of Pt based catalysts in oxygen reduction reaction is the way to reduce the amount of platinum in precious metals. But most of the catalysts are not stable enough.

In the face of this problem, the researchers developed ultrafine platinum nickel rhodium three metal nanowire catalysts by adjusting the size, size and composition of platinum based catalysts. Because the diameter of the nanowire is only one nanometer, the platinum atoms on the surface account for more than 50% of the total platinum atom. This shows high atomic utilization rate and provides a structural basis for high catalytic activity.

The oxygen reduction catalytic test shows that the carbon supported ultrafine platinum nickel rhodium three metal nanowire catalyst has 15.2 times the mass activity of commercial platinum carbon nano catalyst. At the same time, when the catalyst was recycled for 10000 times in an oxygen atmosphere, only 12.8% of the mass loss was achieved. However, the commercial active carbon supported platinum nanomaterials lost 10000 of their mass activity in the oxygen atmosphere for 10000 times. The new catalysts have been significantly improved in quality and catalytic stability, showing good potential for application. (reporter Wu Changfeng)

(Editor: Wang Shaoshao, He Yingchun)

Recommended reading