“…13,14 Unfortunately, even with high conversion and selectivity, the difficult-toisolate catalysts, ligands, and additives in mixed systems will limit their industrial applications to a large scale. 15,16 In recent years, heterogeneous catalysis, especially the catalysts loaded with precious metals, has attracted more and more attention, such as heterogeneous ones based on Au, Pd, Pt, Ru, Ir, and Rh. In the quinoline hydrogenation, the N-heterocyclic ring is easily coordinated with the metal nanoparticles, which makes the catalyst difficult to be recycled.…”