Engineered Pd-Ga alloy nanoparticles through spark ablation and in-flight metal-organic precursor decomposition

Abstract

Pd-Ga alloy nanoparticles with tunable compositions were produced by combining spark ablation with a downstream injection of a metal-organic precursor. This dual-process approach enables control over nanoparticle composition and morphology by adjusting precursor flow rate and sintering temperature. At lower precursor flows, uniform Pd-Ga nanoparticles form, exhibiting stable Pd₅Ga₂ and Pd₂Ga phases. HRTEM and STEM-EDX analyses reveal that as precursor supply increases, Ga incorporation intensifies, leading to structural transitions, phase segregation, and the formation of PdGa dominated phases with amorphous Ga-rich domains, influencing nanoparticle shape and crystallinity. This process unlocks pathways for tailoring alloy compositions in-flight with low-melting point materials.