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[Display omitted] • ZIF-8 derived ZnO@NC can anchor Ru nanoparticles to create Ru-O-Zn interface. • Ru/ZnO@NC achieved complete conversion and 99.2% GVL yield in LA hydrogenation. • Ru/ZnO@NC achieved excellent reaction activity with a TOF of 6032 h−1 at 40 °C. • Reaction mechanism of LA hydrogenation to GVL has been revealed by DFT calculation. • Ru-O-Zn interface can remarkably decline activation energy of rate-determining step. Highly efficient synthesis of valuable γ-valerolactone (GVL) by levulinic acid (LA) hydrogenation is of interest for biomass refinery, but it suffers from great challenge to design highly active Ru-based catalyst at low temperature. ZIF-8 derived ZnO@NC nanocomposite can firmly anchor Ru nanoparticles to create strong Ru-ZnO interfacial structure, as revealed by characterization techniques and DFT calculations. By optimizing Ru content and ZnO particle size, Ru/ZnO@NC achieved excellent reaction activity with a turnover frequency (TOF) of 6032 h−1 at low temperature of 40 °C, which is never reported before. After etching the accessible ZnO, the TOF value was significantly declined to 125 h−1 on Ru/ZnO@NC-HF owing to the lack of effective Ru-ZnO interface. DFT calculation results demonstrate that the Ru-ZnO interfacial structure can facilitate the activation of intermediate CH 3 CHOCH 2 CH 2 COOH* and remarkably decline the activation energy barrier of rate-determining step (CH 3 CHOCH 2 CH 2 COOH + H = HPA) from 1.28 eV to 0.82 eV, thus leading to excellent activity of LA hydrogenation at low temperature. [ABSTRACT FROM AUTHOR]

• TiO 2 nanosheets supported Ru nanoparticles form strong interfacial Ru O Ti structure. • Ru/TiO 2 reached the highest TOF of 19,045 h−1for levulinic acid (LA) hydrogenation. • 99.1% yield of γ-valerolactone (GVL) was achieved over Ru/TiO 2. • DFT calculations clearly elucidate reaction mechanism of LA hydrogenation to GVL. • Ru/TiO 2 interface tunes rate-determining step from LA hydrogenation to cyclization. Highly efficient synthesis of valuable γ-valerolactone (GVL) by levulinic acid (LA) hydrogenation is still a challenge for Ru-based catalysts under mild condition. In this work, we have reported that ultrathin TiO 2 nanosheets supported Ru nanoparticles showed extraordinarily high catalytic activity, GVL yield (99.1%) and reusability owing to the formation of Ru O Ti interfacial structure. The turnover frequency (TOF) reached as high as 19,045 h−1 at 100 °C, much higher than those of Ru/SiO 2 , Ru/GO, Ru/MoS 2 , and commercial Ru/C. DFT calculation elucidates that the dominant reaction pathway of LA hydrogenation to GVL is preferentially hydrogenated to CH 3 CHOCH 2 CH 2 COOH*, followed by cyclization to CH 3 (OH)C 4 OH 4 OH* (GVL − OH) and final dehydroxylation, irrespective of surface structure. Compared to Ru (0 0 2) facet, Ru/TiO 2 interfacial structure changes the rate-determining step from initial hydrogenation to cyclization, which greatly declines the activation barrier from 0.81 eV to 0.48 eV. [ABSTRACT FROM AUTHOR]