Kinetically Controlled Synthesis of Metallic Glass Nanoparticles with Expanded Phase Space

Abstract

Nanoscale metallic glasses offer opportunities for investigating fundamental properties of amorphous solids and technological applications in biomedicine, microengineering, and catalysis. However, the top-down fabrication of metallic glass nanostructure is restricted by the availability of bulk metallic glass; in contrast, the bottom-up synthesis remains rarely explored due to the rigorous formation conditions, especially the extreme cooling rate. Here we develop a kinetically controlled flash carbothermic reaction, featuring ultrafast heating and cooling rates, for the synthesis of metallic glass nanoparticles within milliseconds. Ten permutations of noble metals, base metals, and metalloid (M1-M2-P, M1 = Pt/Pd, M2 = Cu/Ni/Fe/Co/Sn) were synthesized with widely tunable particle sizes and supportive substrates. Through combinatorial development, we discovered a substantially expanded phase space for metallic glass at the nanoscale than that at the bulk scale, revealing an enhanced glass forming ability due to the nanosize effect. Leveraging this effect, we synthesized several nanoscale metallic glasses with elemental compositions that have never, to our knowledge, been synthesized in bulk. The metallic glass nanoparticles show high intrinsic activity in electrocatalysis and heterogeneous catalysis, outperforming crystalline nanoparticle counterparts and commercial precious metal nanoparticle benchmarks.