1 research outputs found
Support Effects in Single-Atom Platinum Catalysts for Electrochemical Oxygen Reduction
Single-atom catalysts
(SACs) provide an ideal platform for reducing
noble-metal usage. SACs also exhibit unusual catalytic properties
due to the absence of a metal surface. The role of the support may
have a significant effect on the catalytic properties, similar to
that of the ligand molecules in homogeneous catalysts. Here, the support
effect was demonstrated by preparing a single-atom platinum catalyst
on two different supports: titanium carbide (Pt1/TiC) and titanium
nitride (Pt1/TiN). The formation of single-atom Pt was confirmed by
STEM, EXAFS, and in situ IR spectroscopy. Pt1/TiC showed higher activity,
selectivity, and stability for electrochemical H<sub>2</sub>O<sub>2</sub> production than Pt1/TiN. Density functional theory calculations
presented that oxygen species have strong affinity into Pt1/TiN, possibly
acting as surface poisoning species, and Pt1/TiC preserves oxygen–oxygen
bonds more with higher selectivity toward H<sub>2</sub>O<sub>2</sub> production. This work clearly shows that the support in SACs actively
participates in the surface reaction and does not just act as anchoring
sites for single atoms