Boron-alloyed porous network platinum nanospheres for efficient oxygen reduction in proton exchange membrane fuel cells

Abstract

Alloying (or doping) non-metals with platinum (Pt) is an advanced solution for the development of high-performance Pt-based electrocatalysts for oxygen reduction reaction (ORR) in proton exchange membrane fuel cells (PEMFCs). Herein, we report boron (B)-alloyed Pt nanospheres (B-PtNSs) with a porous network nanostructure by a combination strategy of confinement reduction and post-boronation. B-alloying can induce effective electronic/geometric structures, strong Pt-B coordination, and lowered d-band center to weaken the binding energy of oxygenated intermediates on the Pt surface. The H2-O2 PEMFC with such a B-PtNSs/C as the cathode catalyst can reach a maximum power density of 1.49 W cm−2, about 1.28 times higher than that of Pt/C. After 30,000 voltage cycles in the range of 0.6 ∼ 0.95 V, only a 14.1 % loss of initial peak power density can be observed, while that with Pt/C declines 45.7 %. Non-metals alloying with Pt-based nanostructures can enable high-performance ORR electrocatalysts for their practical application in PEMFCs.