Kinetically Controlled Synthesis of Metallic Glass Nanoparticles with Expanded Composition Space.

Nanoscale metallic glasses offer opportunities for investigating fundamental properties of amorphous solids and technological applications in biomedicine, microengineering, and catalysis. However, their top-down fabrication is limited by bulk counterpart availability, and bottom-up synthesis remains underexplored due to strict formation conditions. Here, we developed a kinetically controlled flash carbothermic reaction, featuring ultrafast heating (>10 5 K s -1 ) and cooling rates (>10 4 K s -1 ), for synthesizing metallic glass nanoparticles within milliseconds. Nine compositional permutations of noble metals, base metals, and metalloid (M 1 -M 2 -P, M 1 = Pt/Pd, M 2 = Cu/Ni/Fe/Co/Sn) were synthesized with widely tunable particle sizes and substrates. Through combinatorial development, we discovered a substantially expanded composition space for nanoscale metallic glass compared to bulk counterpart, revealing the nanosize effect enhanced glass forming ability. Leveraging this, we synthesized several nanoscale metallic glasses with composition that have never, to our knowledge, been synthesized in bulk. The metallic glass nanoparticles exhibited high activity in heterogeneous catalysis, outperforming crystalline metal alloy nanoparticles. This article is protected by copyright. All rights reserved.