A Sulfite/Air Fuel Cell with Alkali and Sulfuric Acid Byproducts: Bifunctional Electrocatalyst for Sulfite Oxidation and ORR Activity

This work attempted to synthesize bifunctional Pd-Pt bimetallic catalysts for a sulfite/air fuel cell via a simple ethylene glycol reduction method. As-prepared Pd-Pt bimetallic catalysts were characterized by transmission electron microscope, X-ray spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The diameter of the Pt-Pd bimetals was similar to 3-6 nm. The mechanisms of sulfite oxidation and oxygen reduction were investigated. The cell performance was determined to be largely dependent on the sulfite oxidation activity of the catalyst. S(IV) S(VI) is the principal sulfite oxidation reaction for Pd/C, PtPd7.33/C, and PtPd2.75/C, whereas S(IV) -> S(V) is the principal reaction for Pt/C, Pt2.18Pd/C, and PtPd1.22/C. PtPd2.75/C is considered a promising bifunctional catalyst for the sulfite/air fuel cell, which exhibits excellent electrochemical activity and long-term stability. (C) 2021 The Electrochemical Society (ECS). Published on behalf of ECS by IOP Publishing Limited.

Automated summary

This study successfully synthesized bifunctional Pd-Pt bimetallic catalysts for a sulfite/air fuel cell via a simple ethylene glycol reduction method. Characterization of the catalysts revealed that the diameter of Pt-Pd bimetals was around 3-6 nm, and the mechanisms of sulfite oxidation and oxygen reduction were investigated. PtPd2.75/C was identified as a promising bifunctional catalyst for the sulfite/air fuel cell, showing excellent electrochemical activity and long-term stability.