Electron synergy effect in the PtCo/CNTs bimetallic catalysts for promoting highly selective and stable hydrogenation of crotonaldehyde

Herein, we synthesized PtCo/CNTs, Pt/CNTs, and Co/CNTs nanocatalysts at room temperature by chemical reduction method. The synergistic effect in PtCo/CNTs for crotonaldehyde (CAL) hydrogenation is investigated. The nanostructures, morphologies, electronic property, Pt-Co interaction, surface characteristic and composition of the catalysts are examined by XRD, BET, SEM, XPS, HRTEM, STEM, STEM-EDX elemental maps and line profiles and H2-TPD. It is found that Pt and Co forms PtCo bimetallic nanoparticles in the PtCo/CNTs catalyst and the PtCo bimetallic nanoparticles are coated on multi-walled carbon nanotubes. And PtCo/CNTs achieves 83.5% CAL conversion, 91.3% crotyl alcohol (COL) selectivity, and 647.4 h-1 turnover frequency (TOF) at 60 degrees C within 2 h under 3 MPa hydrogen, and its catalytic performance remains basically unchanged after five recycles. Ac-cording to the analysis, the presence of PtCo bimetallic particles lead to electron transferring from Co to Pt (synergy effect), which improves their activation ability of hydrogen and desorption of C--C in COL and thus enhances its selectivity to COL.