Phosphorus-triggered activation of PdPb nanoflowers for enhanced oxygen reduction electrocatalysis

Abstract

The rational development of oxygen reduction reaction (ORR) electrocatalysts with high activity and durability is essential for fuel cells. Here, we synthesize phosphorus-doped palladium–lead nanoflowers (P–PdPb NFs) by a one-pot method using tetrakis(triphenylphosphine)palladium as the phosphorus dopant and CO derived from the decomposition of W(CO)₆ as the reductant and surface-confining agent. The assembled nanosheet structure not only exposes abundant active sites but also enhances the electron transfer ability and inhibits agglomeration and Ostwald ripening. Moreover, the introduction of phosphorus causes the downshift of the d-band center of Pd, leading to decreased oxygen adsorption energy. Thus, ORR performance of P–PdPb NFs in alkaline electrolyte is significantly enhanced, with factors of 4.5 and 2.6 enhancements in mass activity and specific activity compared with those of PdPb NFs, respectively. This work proposes a feasible phosphorus doping strategy for the design of metal–nonmetal electrocatalysts for fuel cells with high performance.