Highly efficient catalysis of dimethyl terephthalate hydrogenation by Ru catalyst loaded on rod-shaped CeO2

• Excellent hydrogenation catalyst prepared from rod-shaped CeO 2 loaded with Ru. • A strong electronic interaction and special Ru n+ interface between Ru and CeO 2 -NR. • Ru/CeO 2 -NR possesses abundant oxygen vacancies and robust Ru n+ -O V -Ce 3+ interactions. • Oxygen vacancies and Ru n+ enhance hydrogen spillover effects. Hydrogenation of aromatic rings is a promising method for synthesizing fine chemicals and for hydrogen storage. Ruthenium-based catalysts are the most common alternatives for expensive palladium catalysts. However, developing efficient Ru-based catalysts for dimethyl terephthalate (DMT) hydrogenation under mild conditions remains challenging. This study addresses this by synthesizing CeO 2 supports with rod-like (CeO 2 -NR), polyhedral (CeO 2 -NP), and cubic (CeO 2 -NC) morphologies via hydrothermal methods, followed by Ru impregnation. Among these, Ru/CeO 2 -NR demonstrated the optimal catalytic performance owing to its highest oxygen vacancy (O V ) concentration, electron-deficient Ru n+ species, and robust Ru-O-Ce interactions. Under optimized conditions (150°C, 5 MPa H 2 , 1 h), Ru/CeO 2 -NR achieved 99.96% DMT conversion and 98.4% selectivity toward dimethyl 1,4-cyclohexanedicarboxylate (DMCD). Remarkably, the catalyst maintained 99.58% conversion and 98.05% selectivity after ten cycles. Despite its low precious metal loading, its catalytic efficacy exceeded that of the industrially widely used Pd/Al 2 O 3 catalysts and thus exhibited certain industrial potential. Density Functional Theory (DFT) simulations revealed that O V and Ru n+ enhanced the adsorption of DMT and H 2 as well as the desorption of DMCD. Furthermore, the significant hydrogen spillover of ruthenium nanoparticles (NPs) was a crucial element contributing to the great hydrogenation efficacy of Ru/CeO 2 -NR. This work provides a mechanistic understanding of morphology-dependent oxygen vacancy engineering in CeO 2 -supported Ru catalysts, offering a strategic pathway for designing durable and efficient systems for plastic-derived aromatic hydrogenation.