Electrocatalysts, and fuel cells containing them

Tong, YuYe J.; Chen, Dejun

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DOE OSTI · 1650928

Electrocatalysts, and fuel cells containing them

Tong, YuYe J.·Chen, Dejun

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Abstract

Provided are electrocatalysts, fuel cells, methods of making fuel cells, and methods of generating an electric current, each featuring a platinum (Pt)-containing substrate in contact with an aqueous solution comprising Pb2+. Electrocatalysts of the invention are formed via underpotential deposition (UPD) when a trace amount of Pb2+ is present in the electrolyte of a half anodic cell for oxidizing formic acid using Pt as the anode. Surprisingly, the UPD process dramatically enhances the activity of formic acid oxidation, at least as much as 10-fold compared with palladium (Pd) black. In an embodiment, the electrocatalyst comprises a Pt-containing substrate, a submonolayer of lead (Pb) adsorbed onto the Pt-containing substrate, and an aqueous solution comprising Pb2+, wherein the concentration of Pb2+ in the aqueous solution is 10 to 500 μm.

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Tong, YuYe J., Chen, Dejun. 2020-05-19. Electrocatalysts, and fuel cells containing them. https://www.osti.gov/biblio/1650928

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