Highly active and stable Co nanoparticles embedded in nitrogen-doped mesoporous carbon nanofibers for aqueous-phase levulinic acid hydrogenation

Abstract

Developing a highly active and durable non-noble metal catalyst for aqueous-phase levulinic acid (LA) hydrogenation to γ-valerolactone (GVL) is an appealing yet challenging task. Herein, we report well-dispersed Co nanoparticles (NPs) embedded in nitrogen-doped mesoporous carbon nanofibers as an efficient catalyst for aqueous-phase LA hydrogenation to GVL. The Co zeolitic imidazolate framework (ZIF-67) nanocrystals were anchored on the sodium dodecyl sulfate modified wipe fiber (WF-S), yielding one-dimensional (1-D) structured composite (ZIF-67/WF-S). Subsequently, Co NPs were uniformly embedded in nitrogen-doped mesoporous carbon nanofibers (CoRNC/SMCNF) through a pyrolysis-reduction strategy using ZIF-67/WF-S as the precursor. Benefiting from introducing modified wipe fiber WF-S to enhance the dispersion of Co NPs, and Co0 with Co-Nx dual active sites, the resulting CoRNC/SMCNF catalyst shows brilliant catalytic activity (206 h−1 turnover frequency). Additionally, the strong metal–support interactions greatly inhibited the Co NPs from aggregation and leaching from the mesoporous carbon nanofibers, and thus increasing the reusability of the CoRNC/SMCNF catalyst (reusable nine times without notable activity loss).