Macroscopic graphite felt containing palladium catalyst for liquid-phase hydrogenation of cinnamaldehyde

[Display omitted] •Structured catalyst consisting of oxygen functionalized graphite felt (OGF) supported highly dispersed Pd nanoparticles.•Abundant oxygenated groups decorated structural defects and porous structure on OGF.•Strong metal-support interaction from charge transfer at Pd-carbon interface in Pd/OGF.•Monolith Pd/OGF as efficient catalytic stirrer with easy recyclability for liquid-phase hydrogenation of cinnamaldehyde. Developing of both effective and stable noble metal nanoparticle (NPs) catalysts with easy catalyst-product recovery is still challenging in the liquid-phase catalytic processes. Here, we report on the synthesis of a hierarchical structured catalyst that consisted of oxygen functionalized graphite felt (OGF) support for liquid-phase processes. The monolith palladium-based catalyst was used as catalytic stirrer and displays excellent stability as well as complete recyclability for liquid-phase hydrogenation of α, β-unsaturated cinnamaldehyde. The surface defects decorated with abundant oxygenated groups as well as highly accessible porous structure generated from the acid treatment of carbon support, construct a bridge between Pd and support providing the charge transfer to alter the metal-support interactions. The electron-deficient high-valent Pdδδ+ species, formed on the metal NPs, and defects on the support help to enhance the Pd dispersion and resistance to sintering and/or aggregation during both catalyst preparation and cycling tests, leading to the high and stable hydrogen dissociative adsorption for hydrogenation process.