Abstract: A novel Pd-Ni bimetallic nanoparticle catalyst supported on epigallocatechin-3-gallate (EGCG) grafted collagen fiber (CF), Pd-Ni/CF-EGCG, has been prepared. EGCG was selected as a bridge molecule to anchor Pd-Ni nanoparticles and control the size and distribution of Pd-Ni nanoparticles. The morphology and physical properties of this catalyst were characterized by thermo-gravimetric analysis, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and X-ray diffraction. It was observed that this catalyst was in an ordered fibrous state, and well-dispersed Pd-Ni nanoparticles with an average diameter of 2.2 nm formed at the outer surface of CF. Hydrogenation of nitrobenzene catalyzed by Pd-Ni/CF-EGCG was investigated. An optimal synergistic action can be achieved when the molar ratio of Ni/Pd was 0.8, and the turnover frequency (TOF) was 237 min^-1 at 308 K and 1.0 MPa, which is twice as high as that of Pd/CF-EGCG. Pd-Ni/CF-EGCG still has higher activity after reuse five times.

Key words: collagen fiber, epigallocatechin-3-gallat, palladium, nickel, bimetallic catalyst, nitrobenzene, hydrogenation