| Summary: | The pursuit of operational advancements in direct formic acid fuel cells (DFAFCs) necessitates the development of high-performance platinum (Pt)-based catalysts for formic acid electrooxidation (FAOR). However, FAOR on Pt-based catalysts follows a dual pathway mechanism, in which the direct pathway is a preferred route due to its efficient dehydrogenation process. Conversely, the indirect pathway results in the generation of adsorbed CO species, a process that deleteriously poisons the active sites of the catalyst, with CO species only being oxidizable at higher potentials, causing a significant compromise in catalyst performance. Herein, we have successfully synthesized Pt-C<sub>3</sub>N<sub>4</sub>@CNT, where three Pt clusters are precisely dispersed in a triplet form within the C<sub>3</sub>N<sub>4</sub> by virtue of the unique structure of C<sub>3</sub>N<sub>4</sub>. The mass activity for the direct pathway (0.44 V) delivered a current density of 1.91 A <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msubsup><mrow><mi>mg</mi></mrow><mrow><mi>Pt</mi></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msubsup></semantics></math></inline-formula>, while the indirect pathway (0.86 V) had no obvious oxidation peak. The selectivity of Pt-C<sub>3</sub>N<sub>4</sub>@CNT catalysts for the direct pathway of FAOR was improved due to the special structure of C<sub>3</sub>N<sub>4</sub>, which facilitates the dispersion of Pt tri-atoms in the structure and the electronic interaction with Pt. In this study, we provide a new strategy for the development of highly active and selective catalysts for DFAFCs.
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