PtBi Intermetallic Compounds with Enhanced Stability towards Base-Free Selective Oxidation of Glycerol

Designing efficient and stable catalysts for base-free oxidation of glycerol toward targeted products is highly desirable but remains challenging. Herein, carbon nanotube (CNT)-supported PtBi-ordered intermetallic compounds (O-PtBi/CNT) were prepared with the aim of enhancing their catalytic performance in preferential oxidation of the secondary hydroxyl group of glycerol. Performance tests show that the O-PtBi/CNT catalyst with high percentage of Pt⁰ species and ordered atomic distribution affords high selectivity to dihydroxyacetone (DHA) from the oxidation of secondary hydroxyl group in comparison with the referred bimetallic catalyst (Pt–Bi/CNT) as well as the monometallic one (Pt/CNT). Moreover, the O-PtBi/CNT catalyst adsorbs DHA more strongly than the Pt–Bi/CNT catalyst as revealed by DFT calculations, thus promoting its further oxidation to hydroxypyruvic acid. The stability of the O-PtBi/CNT catalyst is also enhanced against the Pt–Bi/CNT catalyst due to its structure remaining almost unchanged during the reaction.