Constructing a Pd–Co Interface to Tailor a d-Band Center for Highly Efficient Hydroconversion of Furfural over Cobalt Oxide-Supported Pd Catalysts

Abstract

Cobalt is an alternative catalyst for furfural hydrogenation but suffers from the strong binding of H and furan ring on the surface, resulting in low catalytic activity and chemoselectivity. Herein, by constructing a Pd−Co interface in cobalt oxidesupported Pd catalysts to tailor the d-band center of Co, the concerted effort of Pd and Co boosts the catalytic performance for the hydroconversion of furfural to cyclopentanone and cyclopentanol. The increased dispersion of Pd on acid etching Co 3 O 4 promotes the reduction of Co 3+ to Co 0 by enhancing hydrogen spillover, favoring the creation of the Pd−Co interface. Both experimental and theoretical calculations demonstrate that the electron transfer from Pd to Co at the interface results in the downshift of the d-band center of Co atoms, accompanied by the destabilization of H and furan ring adsorption on the Co surface, respectively. The former improves the furfural hydrogenation with TOF on Co elevating from 0.20 to 0.62 s −1 , and the latter facilitates the desorption of formed furfuryl alcohol from the Co surface for subsequently hydrogenative rearrangement of the furan ring to cyclopentanone on acid sites. The resultant Pd/Co 3 O 4 -6 catalyst delivers superior activity with a 99% furfural conversion and 85% overall selectivity toward cyclopentanone/cyclopentanol. We anticipate that such a concept of tailoring the d-band center of Co via interface engineering provides novel insight and feasible approach for the design of highly efficient catalysts for furfural hydroconversion and beyond.

Fabrication of Fe–Zr, Co–Zr, and Ni–Zr Catalysts to Boost CNTs Synthesis from Plastic Wastes and the Electrocatalytic Oxygen Evolution Reaction

“…The H 2 -consumption peaks at 370, 530, and 610 °C can be attributed to the conversion of Fe 2 O 3 to Fe 3 O 4 , Fe 3 O 4 to FeO, and FeO to metallic Fe, respectively . Both Co–Zr and Ni–Zr exhibited a clear H 2 consumption in the H 2 -TPR curves at 300–500 °C, and it can be attributed to the reduction of Co 3 O 4 and NiO to metallic Co and Ni, respectively. − It indicated that Co–Zr and Ni–Zr exhibited similar reducibility, which was higher than that of Fe–Zr.…”

Tuning the d-Band Center of Co3O4 via Octahedral and Tetrahedral Codoping for Oxygen Evolution Reaction

“…It is widely accepted that the d-band center (ε d ) can be used as a descriptor of the transition metal binding adsorbate tendency. − The ε d level of the adsorption Co sites for Co 3 O 4 , Al–Co 3 O 4 , Ga–Co 3 O 4 , Fe–Co 3 O 4 , Ni–Co 3 O 4 , and In–Co 3 O 4 is −2.446, −2.820, −2.795, −2.543, −2.786, and −2.391 eV, respectively (Figure a–c and Table S12). The PDS energy barriers should present a reverse volcanic trend versus the d-band center of the adsorption Co sites (Figure i).…”