Structure and size control of FePtCu nanocatalysts for high performance hydrogen evolution reaction

Pt-based nanostructures with low Pt content are attractive electrocatalysts for high-efficiency hydrogen evolution reaction. It's a challenge to simultaneously tailor the structure and size of Pt-based alloys in a simple manner and boost their electrocatalytic efficiency. Here, we report the synthesis of high performance Fe45Pt35Cu20 nanoparticles (NPs) with a well-controlled size and crystal structure by a simple organometallic method. Size control of the particles was realized in the range of 8 nm to 27 nm by simply varying the type of Fe precursor, and with the increase of particle size the Fe45Pt35Cu20 alloys exhibited a higher degree of chemical ordering (fct phase, namely L1(0) structure). The FePtCu nanoparticles showed superior catalytic activity and stability towards the hydrogen evolution reaction with a notably low Tafel slope of 24 mV dec(-1) (0.5 M H2SO4) in comparison to commercial Pt/C catalysts. The work provides a simple strategy for tailoring the size and crystal phase of Pt based nanostructures to facilitate their promising application in catalytic reactions.