Uniformly dispersed Pd nanoparticles anchored Co(OH)₂/Cu(OH)₂ hierarchical nanotube array as high active structured catalyst for Suzuki–Miyaura coupling reactions

Up to now, although tremendous effort has been made in exploring Pd-based catalysts for the Suzuki–Miyaura coupling reactions, there is still much room to enhance its catalytic performance by synthesis catalyst with define-designed and tailored structure. Herein, a new kind of Pd-based structured catalyst with hierarchical hollow structure (Pd/Co(OH)₂/Cu(OH)₂/copper foam) has been successfully synthesized by three facile steps. As framework, the hierarchical hollow nanoarray structure of Co(OH)₂/Cu(OH)₂/copper foam is fabricated by immersion and electrolytic deposition methods. Uniformly dispersed Pd nanoparticles with a narrow size distribution (1.5 ± 0.2 nm) are anchored on the surface of the hierarchical nanotube array through an in situ spontaneous redox reaction between Co(OH)₂ and PdCl₄²⁻ without any surfactant at room temperature. Compared with other synthesis approaches, it just takes less than 1 h for the whole fabrication process in our strategy, exhibiting very high efficiency. In order to evaluate the catalytic performance of the as-prepared structured catalyst, 16 kinds of reagents were chosen as substrates for Suzuki–Miyaura coupling reaction, exhibiting excellent activity and reusability under mild conditions. We hope this simple and efficient method will open a new strategy to design and prepare structured catalysts.