Sub-2 nm PtBi alloy nanoparticles on Bi-N-C single-atom catalyst for selective oxidation of glycerol to 1,3-dihydroxyacetone

Nanoscale metal particle-decorated single-atom catalysts (SACs) have been widely used in the fields of photocatalysis, electrocatalysis and thermal catalysis due to the combination of the advantages of nanoparticles and SACs. Herein, a strategy based on Pt-Bi atomic exchange is proposed for the formation of ultrafine (sub-2 nm) PtBi nanoclusters on single atomic Bi-N-C. The dynamic structural evolution between single atomic Bi-N-C on nitrogen-doped carbon nanosheets and Pt nanoclusters on the reconfiguration of stable PtBi alloy nanoparticles was demonstrated through a spherical aberration-corrected transmission electron microscope, X-ray absorption spectroscopy and density functional theory calculations. By our synthesis strategy, the Bi-N-C sites significantly improve the dispersion of PtBi alloy nanoparticles, resulting in a high turnover frequency of up to 224.4 h-1 and the 1,3-dihydroxyacetone selectivity of 77.4%, 3.5 times higher than that of commercial 5Pt/C. On the other hand, the strong interaction between SAC and nanoparticles enhanced the catalytic stability by preventing leaching of Bi. It opens new avenues toward the rational design of high-performance nanoparticle-SACs, enabled by the in-depth understanding of the interaction between nanoparticles and SACs, which determines the structure of real active sites.