• • Nd-Ni-BTC achieves 100% DCPD conversion at 100 °C, 2 MPa H2, and 10 h, with no loss in activity after seven consecutive recycling runs, demonstrating operational stability that exceeds conventional Ni-based catalysts (e.g., Raney nickel) which suffer from mechanical attrition and regeneration challenges.
• • The incorporation of Ni into RE-MOFs creates Ni–O4 coordination and defect-induced RE–O frustrated Lewis pairs (FLPs), as confirmed by structural and spectroscopic analyses; this dual-site architecture enhances Lewis acid-base properties, enabling selective hydrogenation of DCPD to endo-THDCPD without noble metals.
• • Nd-Ni-BTC outperforms Ce-Ni-BTC by a measurable margin in conversion and selectivity, attributed to the smaller ionic radius and higher charge density of Nd3+ that strengthen substrate adsorption/desorption; this lanthanide-dependent performance provides a design rule for tuning FLP strength in MOF catalysts.
• • The catalyst maintains crystallinity and structural integrity after seven cycles, as evidenced by unchanged PXRD patterns and Ni K-edge XAS spectra, overcoming the trade-off between defect generation and framework stability that plagues conventional defective MOFs.