Metal organic framework (MOF) derivatives, porous N-doped carbons (CN), can be used as catalyst carriers owing to their excellent structural properties. The microstructures of MOF-derived carbon materials are affected considerably by the atmosphere in which the parent MOFs are pyrolyzed. In this study, a hierarchically porous N-doped carbon hybrid of carbon nanotubes and a porous carbon framework (denoted CN-H) was fabricated by pyrolysis in a H2/Ar atmosphere followed by acid etching, and subsequently, a Pd@CN-H catalyst was synthesized by the addition of Pd nanoparticles on the porous N-doped carbon support. The pyrolysis atmosphere and etching treatment significantly affected the morphology, specific surface area, meso/macropore ratio, and composition of the porous N-doped carbon materials, as well as the catalytic properties of the Pd@CN catalysts for the selective hydrogenation of phenol to produce cyclohexanone. Nitrogen adsorption–desorption measurements and inductively coupled plasma atomic absorption spectroscopy analyses confirmed that pyrolysis in a H2/Ar atmosphere and acid etching significantly increased the number of meso/macropores in Pd@CN-H, thus enhancing the Pd loading and phenol adsorption. As a result of the increased porosity, Pd loading, and phenol adsorption, the cyclohexanone selectivity and phenol conversion were improved. Furthermore, the as-fabricated Pd@CN-H catalyst displayed good reusability in recycling tests. These results provide insights into the synthesis of MOF-derived hybrid carbon materials and their possible utilization in catalysis.

Covalent organic frameworks (COFs) have emerged as an excellent support for heterogeneous catalysis due to their regular pore structure and high specific surface area. Herein, a series of porous TpPa-1 with different morphologies and structures were achieved by adjusting the ratio of water to acetic acid in the solvent-thermal process,

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Zeolite imidazolate frameworks (ZIFs) derivatives, porous N-doped carbon (CN) materials, show outstanding performance when used as catalyst supports. The characteristics of ZIFs affect significantly the microstructure of CN. In this work, a series of CN materials were fabricated through direct pyrolysis of Zn/Co-ZIFs and Pd@ CN catalysts were achieved by loading Pd nanoparticles. The results underline that the Co content in Zn/Co-ZIFs influences considerably the properties of CN and the catalytic activity of Pd@CN for the phenol hydrogenation to cyclohexanone. N 2 adsorption−desorption, CO 2 -TPD, and ICP analyses confirm that the increase of Co in ZIFs can enhance significantly the mesoporous ratio of CN for improving the loading and dispersion of Pd and increase the basic sites of CN materials for improving the phenol adsorption. As a result, significantly enhanced phenol conversion with similar cyclohexanone selectivity is achieved. These findings provide deep insights for the fabrication of ZIF-derived CN materials and their applications in catalysis.

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One-step hydrogenation of phenol is a green approach to produce cyclohexanone, an important intermediate for the synthesis of nylon. The design and fabrication of high-performance catalysts still present a great challenge. Herein, a series of triazinyl covalent organic frameworks (PC-COFs) were prepared by adjusting the synthesis time using a solvothermal method, and then, Pd@PC-COF catalysts were fabricated by anchoring Pd. Controlling the synthesis time can lead to the fabrication of PC-COFs with high crystallinity, large specific surface area, abundant mesopores, and rich N element, increasing the Pd content with higher Pd(0) proportion and enhancing the mass transfer, thereby improving the catalytic performance of Pd@PC-COFs for phenol hydrogenation. The as-fabricated catalyst has good reusability during the reaction cycles of phenol hydrogenation. This work develops an efficient approach to fabricate high-performance Pd-based catalysts for phenol hydrogenation.

A novel two-dimensional ZIF-derived Pd@CN prepared via one-step calcination exhibits outstanding catalytic activity in heterogeneous catalysis. The well-developed porous structure, low dimension and low density make active sites more accessible....