l-Lysine derived fabrication of Cu@Ni core–satellite nanoassemblies as efficient non-Pt catalysts for the methanol oxidation reaction

Abstract

Designing cost-effective, highly active, and durable noble-metal-free electrocatalysts as alternative electrode materials for the methanol oxidation reaction (MOR) is of significant importance for practical applications. Herein, we report a facile one-pot synthetic route to construct Cu@Ni core–satellite nanoassemblies (CS-NAs) with the assistance of eco-friendly L-lysine, which involves the spontaneous process of preferential formation of the Cu core followed by self-assembly growth of Ni satellites. The selection of the Cu core is beneficial for enhancing the charge transfer and tuning the electronic structure of Ni satellites, as well as serving as a self-skeleton to enhance the structural stability for catalysis. Meanwhile, the tiny Ni satellites could be fully exposed, which not only produce a larger number of valid active sites, but also provide a short electron and ion transport distance. As a result, the Cu@Ni CS-NAs are qualified as superior and durable electrocatalysts for the MOR, affording 29.6 mA cm⁻² at 1.6 V with long-term chronoamperometric stability.