A new method for small-sized platinum intermetallic fuel cell catalysts

Platinum performs a most important function in gas cell catalysts however restricts the commercialization of gas cells as a result of its excessive value. Given this limitation, scientists developed intermetallic compounds (IMCs) as a promising low-Pt electrocatalyst.

Nonetheless, the synthesis of IMCs stays troublesome as a result of direct high-temperature annealing simply results in alloy sintering, enlarging the nanoparticle and inflicting a lower in Pt availability.

Not too long ago, a analysis group led by Professional. Liang Haiwei from the College of Science and Expertise (USTC) of the Chinese language Academy of Sciences developed a small molecule-assisted impregnation method to realizing the overall synthesis of carbon-supported platinum intermetallic gas cell catalysts. The examine was printed in Nature Communications.

Beforehand, Liang’s staff and collaborators realized sulfur-anchoring synthesis. Nonetheless, the usage of commercialized carbon black propelled the invention one step nearer to widespread utility.

Within the analysis, scientists first screened some small molecules containing heteroatoms as components within the impregnation and suppressed PtCo sintering, taking the additive-free group as a management.

“Notably, sulfhydryl group-containing molecules…exhibited excellent capability for suppressing PtCo sintering,” the researchers wrote within the paper, and water-soluble sodium thioglycolate (STG) stands out to be the optimum additive.

After that, the situations of annealing have been optimized to synthesize 18 binary Pt-IMCs catalysts with comparatively small particle sizes, and the evidenced construction met expectations, that includes a uniformed distribution of nanoparticles, base steel parts, and atoms. Six synthesized catalysts have been examined and confirmed wonderful exercise, capability, and sturdiness.

Why does STG work? STG, in line with the examine, coordinates with Pt and Co by way of a sulfhydryl group and a carboxylate group to type the precursors, which step by step decompose throughout annealing and type PtCo bimetallic clusters, releasing STG. The STG lastly converts right into a bodily protecting carbon coating and offers chemical Pt-S interplay with doped S to suppress PtCo sintering.

The analysis has additionally shed some mild on the appliance of Pt intermetallic catalysts in different energy-conversion-related electrocatalysis and heterogeneous catalysis.