Research groups at Tohoku University, Hokkaido University, and the University of Electro-Communications have succeeded in producing a highly active non-platinum oxygen reduction catalyst using a very simple process.
Fuel cells and metal-air batteries, which are expected to replace lithium-ion batteries as next-generation batteries, extract energy by causing an oxygen reduction reaction on the positive electrode.Since the oxygen reduction reaction is difficult to proceed, a carbon catalyst carrying platinum is generally used. However, platinum is expensive and resource-constrained, and an inexpensive catalyst electrode material to replace platinum has been sought.
The researchers focused on iron-phthalocyanine-based organic metal complexes that have a molecular-like structure called heme and are used in pigments and the like.For example, in hemoglobin contained in blood, oxygen is carried into the body by binding iron molecules and oxygen molecules in heme.Inspired by the adsorption mechanism of iron atoms and oxygen molecules, the surface of the carbon material was modified with an iron phthalocyanine-based organic metal complex, and it was found that it exhibited extremely active oxygen reduction reaction characteristics.At the same time, by combining theoretical calculations, we succeeded in theoretical analysis of the high activation.
Conventional electrode fabrication of non-platinum metal carbon catalysts requires a process of firing under an inert gas at high temperature, but the process of modifying this catalyst molecule does not require firing and can be manufactured by a wet process. is.In addition to being able to significantly reduce process costs, this catalyst, which is an iron-based organic metal complex, can be expected as an inexpensive non-platinum catalyst with no resource restrictions.
With this result, it is expected that the spread of these energy devices will be promoted through the deplatination of fuel cells and metal-air batteries.
