Designing PdxCuy octahedra alloy nanocatalysts supported on solid substrates for solvent-free sonogashira cross-coupling reaction: Rational optimization of metal precursors

Abstract

The current research details a scientific inquiry into an economic, reproducible, and adaptable synthetic process for the formation of PdxCuy octahedra (Oh) alloy nanocatalysts. Herein, several alloys such as Pd3Cu7, Pd4Cu6, Pd5Cu5, Pd6Cu4, and Pd7Cu3 are synthesized by altering the metal precursors quantities, resulting in a specific octahedral shape for all the ratios. After a thorough optimization study, Pd6Cu4 alloy was selected and anchored onto three solid substrates to achieve Pd6Cu4@hBNNs, Pd6Cu4@ZrO2 and Pd6Cu4@GONs nanocatalysts. Furthermore, the nanocatalysts were investigated for the Sonogashira cross-coupling reaction under solvent-free conditions, with the 15 wt% of the metal-support ratio of Pd6Cu4@hBNNs exhibiting remarkable catalytic activity when compared to the other two supported nanocatalysts. In advance, highly active Pd6Cu4@hBNNs nanocatalyst has many advantages, including mild reaction conditions, benign and minimum reaction duration. Moreover, the catalyst showed an efficient yield of 95 % for the model Sonogashira cross-coupling and considerable recyclability up to the 8th consecutive cycle achieving a 65 % yield. The outstanding performance of this economically viable nanocatalyst is most likely influenced by the synergistic effect of the catalyst and its strong metal-support contact.