Fabrication of multi-metal alloy nanocatalysts using microplasma electrolytic oxidation for high-efficiency catalysis

Multimetallic alloy nanocatalysts are of significant interest due to their superior catalytic properties, offering substantial advantages for chemical conversion and petroleum refining applications. However, conventional powder-based multimetallic catalysts often face issues such as non-uniform dispersion of active components and challenging catalyst recovery. In this study, we propose a novel in-situ synthesis method for multimetallic alloy nanocatalysts via microplasma electrolytic oxidation (MPEO) on helical magnesium and aluminum wire substrates. This microplasma-based approach generates localized high temperatures and pressures conditions, effectively decomposing precursor salts into uniformly dispersed alloy nanoparticles. Specifically, two multimetallic alloy nanocatalysts; Fe_3.4Co_2.7Ni_3.3Ru_1.3Pd_0.74 and Fe_2.7Co_2.9Ni_2.9Ru_2.3Pt_0.2, were successfully synthesized on magnesium and aluminum wire surfaces, respectively. Detailed characterization via scanning electron microscopy (SEM) and transmission electron microscopy (TEM) confirmed the porous surface morphology and uniform distribution of active catalytic components. Catalytic performance tests revealed demonstrated exceptional performance; the Fe_3.4Co_2.7Ni_3.3Ru_1.3Pd_0.74 nanocatalyst exhibited a high acetylene hydrogenation conversion of 99.79 % with selectivity up to 94.99 %, whereas the Fe_2.7Co_2.9Ni_2.9Ru_2.3Pt_0.2 nanocatalyst demonstrated a hydrogen production rate of 0.197 mL/s during sodium borohydride hydrolysis. These findings highlight the potential of MPEO technique as a promising pathway for fabricating multimetallic alloy nanocatalysts with broad catalytic applications.