Retracted Article: Monodisperse CuB23 nanoparticles grown on graphene as highly efficient catalysts for unactivated alkyl halide Heck coupling and levulinic acid hydrogenation

Abstract

Monodisperse CuB₂₃ nanoparticles were successfully grown on graphene by the co-reduction of graphene oxide and Cu(NH₃)₄²⁺ using KBH₄ and with the assistance of solution plasma. Graphene is a powerful dispersion agent and a distinct support for CuB₂₃ nanoparticles. Unexpectedly, we found that the prepared CuB₂₃/graphene catalyst imparts exceedingly high activity to the Heck-type coupling of unactivated alkyl halides with alkenes and the liquid phase hydrogenation of levulinic acid to γ-valerolactone. Additionally, the as-prepared CuB₂₃/graphene also exhibited excellent recyclability during the hydrogenation of levulinic acid. The excellent catalytic performance might be caused by the combined effect of the good dispersion of CuB₂₃ nanoparticles and the interaction between graphene and CuB₂₃ nanoparticles. This not only facilitates electron transfer and mass transport but also improves thermal stability during the catalytic reaction process.