Selective hydrogenation catalysis enabled by nanoscale galvanic reactions

Abstract

By mimicking nanoscale galvanic reactions, this study focuses on optimizing catalytic hydrogenation by introducing two spatially separated sites for the activation of H₂ into proton and electron pairs and the selective reduction of –NO₂. The catalyst system is designed with the co-deposition of Pt and Fe₂O₃ nanoparticles on conductive carbon nanotubes, establishing an electron-transferring pathway. Protic solvents facilitate proton transport. Upon activation of H₂ molecules into proton and electron pairs on Pt, modified with ammonia or amines, these active species are efficiently transferred to Fe₂O₃ nanoparticles for the selective reduction of –NO₂ into amines without affecting other functional groups. Compared with Pt/CNT, which easily hydrogenates both C=C and –NO₂ groups of 4-nitrostyrene, the Pt&Fe₂O₃/CNT catalyst modified by NH₃ exhibits higher activity and selectivity for –NO₂ hydrogenation. Electrochemically, Pt functions as the anode for the hydrogen oxidation reaction, while Fe₂O₃ acts as the cathode, selectively reducing –NO₂.