Unveiling the role of the Co-Zr interface in Fischer-Tropsch synthesis using inverse Co-ZrO2 catalysts

• The Co–Zr interface serves as a structure-independent activity descriptor, universally enhancing FTS performance across Co(10–11), (0001), and (11–20) facets. • Co-Zr interfaces formation facilitate electron transfer, promoting CO/H₂ dissociation and suppressing CH₄ formation. • NMS-Co-4Zr achieves 93.9 % C 5 + selectivity and ≤1.7 % CH₄ at 170 °C. • Co-Zr interface universally reduces reaction temperature by 30–110 °C. • Inverse catalyst strategy clarifies ZrO₂ promotion mechanism for FTS. This study clarifies the ambiguous promotional mechanism of ZrO₂ in conventional cobalt-based Fischer-Tropsch synthesis (FTS) catalysts by constructing inverse Co-ZrO₂ model systems. Hexagonal close-packed (HCP) Co nanocrystals with well-defined exposed facets ((10–11), (0001), (11–20)) were synthesized, and ZrO₂ was deposited onto their surfaces to eliminate interference from traditional supports. The optimal catalyst (NMS-Co-4Zr, 10–11) facets with 4wt% Zr) achieves exceptional performance: 93.9% C 5 + selectivity with ≤1.7% CH₄ formation at 170 °C, accompanied by robust 240 h stability. Advanced characterizations confirm the formation of Co-Zr interface, where electron transfer from ZrO 2 to Co facilitates the dissociation of CO and H₂. Notably, the promotional effect of the Co-Zr interface is universal across different Co facets: it lowers reaction temperatures by 30–110 °C and elevates C 5 + selectivity to 85.5–93.9% for all modified catalysts. This work establishes the Co-Zr interface as a structure-independent activity descriptor, providing a paradigm for targeted interfacial engineering in the design of high-efficiency FTS catalysts. By constructing inverse catalysts to form Co-Zr interfaces, the Fischer-Tropsch synthesis performance of Co-based catalysts is universally enhanced through the synergistic effect of electron transfer and oxygen vacancies. The inverse catalyst strategy provides an ideal model for interface engineering and can be extended to other heterogeneous catalytic systems.