Electrodeposited palladium on MWCNTs as 'semi-soluble heterogeneous' catalyst for cross-coupling reactions

•Nano-sized Pd catalyst was electro-synthesized on MWCNTs from aqueous media.•We recognized Pt-carbon electronic interaction by X-ray photoelectron spectroscopy.•Pd-MWCNTs showed superior catalytic activity toward Suzuki-Miyaura and Sonogashira reactions.•The Pd-MWCNTs can be recovered and re-used.

Platinum group metals (PGM) catalyze many important chemical processes including hydrogenation; electro-catalysis applied to fuel cell and battery technologies and one of the most prominent the Csp2-Csp2 cross-coupling reactions such as Sonogashira, Suzuki-Miyaura, and Csp2-Nsp3 cross-coupling as for the Buchwald-Hartwig type reactions.The main concern of the catalytic reaction is the recovery and recyclability of used catalytic entities. Recent efforts in the catalyst fabrication focus on combining a nano-sized metal with various high surface area supports like resins or carbon-based materials that allow recovering the catalyst after each reaction in a simple and convenient way. This work aims to investigate the catalytic activity of the carbon-supported (MWCNTs) electrodeposited metallic nanoparticles (Pd) and their applications in several cross-coupling reactions. We propose a simple and affordable synthesis of the high surface area Pd-C composite that can be re-used until deactivated. The intramolecular interactions between carbon and metallic fractions studied by X-ray photoelectron spectroscopy are discussed with respect to the catalytic efficiencies.

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