▎ 摘　　要

The development of carbon-based metal-free electrocatalysts for oxygen reduction reaction (ORR) is essential for large-scale commercial applications of fuel cells. Using density functional theory computations, we explore the potentials of a novel boron-doped graphene nanoribbon (BGNR) as an excellent electrocatalyst for ORR in an acidic environment. The plausible reaction pathways are studied, and the optimal reaction mechanism is identified. Our results show that ORR at BGNR prefers to proceed through a four-electron OOH pathway. The overpotential for ORR on BGNR is calculated to be 0.38 V, which is lower than that on the Pt-based catalysts (0.45 V). For comparison, we study the catalytic activity of the single B-doped graphene nanoribbon (S-BGNR) and B-doped graphene (BG) for ORR. Remarkably, the para-B distribution on BGNR leads to high affinity for O-2 adsorption and excellent catalytic activity, which is superior to S-BGNR and BG. Our results indicate that BGNR is a promising metal-free ORR catalyst for fuel cells.