Trace Iron-Modified CeO₂-Supported Core-Shell CoO@Co Catalyst for Selective Conversion of Furfural to 1,5-Pentanediol

Graphical The CoO@Co core-shell catalyst, 7Co-0.2Fe/CeO 2 , efficiently catalyzes the hydrogenation and ring-opening of furfural to 1,5-pentanediol, with a high productivity of 54.76 mmol/g Co /h, representing the top activity level among the reported catalysts. The addition of Fe optimizes the Co 2+ /Co 0 ratio, improves substrate adsorption, and prevents the formation of tetrahydrofurfuryl alcohol, a saturated furan byproduct. In the conversion of furfural using non-noble metal catalysts, preferential cleavage of the C2−O bond followed by hydrogenation of the C=C bond facilitates selective access to valuable 1,5-pentanediol (1,5-PeD). Herein, we developed CeO₂ loaded core-shell CoO@Co nanoparticle catalysts. Adjusting Co loading, Fe doping, and reduction temperature improved reaction efficiency. 7Co-0.2Fe/CeO₂ catalysts reduced at 500 °C demonstrated optimal performance. 1,5-PeD produced at 54.76 mmol/g Co /h, representing the top activity levels among the reported catalysts. H₂-TPR, XRD, HAADF-STEM, FT-IR, XPS, and XANES were employed to investigate the catalyst structure-activity relationship. Co 2+ cleaves furan ring C−O bond, Co⁰ promotes double-bond hydrogenation. The CoO@Co structure favors the desired 1,5-PeD production route. Trace Fe species optimize the Co 2+ /Co⁰ ratio, enhance the substrate adsorption, and inhibit the furan ring saturation. These findings emphasize the importance of fine-tuning catalyst structure and composition for selectivity improvement.