Tuning oxygen vacancy in SnO2 inhibits Pt migration and agglomeration towards high-performing fuel cells

The serious durability concerns of carbon supported Pt electrocatalysts for oxygen reduction reaction (ORR) have strictly limited the commercialization of fuel cells. Herein, cable-like carbon nanotubes (CNTs)@SnO2 core@shell supports with regulable electronic metal-support interaction (EMSI) are designed for Pt nanoparticles (NPs) as ORR catalysts. Impressively, the best-performing Pt-CNT@SnO2 catalyst with optimized d-band center achieves an excellent activity (mass activity (MA) of 0.68 A mgPt−1 at 0.9 ViR-free and peak power density of 1618 mW cm−2) and record-high durability in H2-O2 fuel cells (9.2 % MA and 8 % power density loss after 5k cycles under 1.0–1.5 V) among the reported Pt-based catalysts, which is also superior to the U.S. DOE 2025 targets. Density functional theory (DFT) calculations reveal that the strong metal-support bonding interaction (SMSBI) endows much larger adhesion energy and migration barrier towards Pt atoms compared to carbon supports, leading to the extraordinarily high stability in fuel cells.