Pt1-xNix Alloy Nanoparticles Embedded in Self-Grown Carbon Nanofibers: Synthesis, Properties and Catalytic Activity in HER

The development of new heterogeneous Pt-containing catalysts has retained its relevance over the past decades. The present paper describes the method to produce metal-carbon composites, Pt1-xNix/CNF, with an adjustable Pt/Ni ratio. The composites represent Pt1-xNix (x = 0.0-1.0) nanoparticles embedded within a structure of carbon nanofibers (CNF). The synthesis of the composites is based on a spontaneous disintegration of Pt1-xNix alloys in an ethylene-containing atmosphere with the formation of CNF. The initial Pt1-xNix alloys were prepared by thermolysis of multicomponent precursors. They possess a porous structure formed by fragments of 100-200 nm. As was shown by X-ray diffraction analysis, the crystal structure of the alloys containing 0-30 and 60-100 at.% Ni corresponds to a fcc lattice based on platinum (Fm-3m), while the Pt0.50Ni0.50 sample is an intermetallic compound with the tetragonal structure (P4/mmm). The impact of the Ni content in the Pt1-xNix samples on their activity in ethylene decomposition was studied as well. As was revealed, the efficiency of Pt1-xNix alloys in this process increases with the rise of Ni concentration. The composite samples were examined in an electrochemical hydrogen evolution reaction. The synthesized Pt1-xNix/CNF composites demonstrated superior activity if compared with the Pt/Vulcan commercial catalyst.

Automated summary

The development of new heterogeneous Pt-containing catalysts has remained relevant over the past decades. This paper presents a method for producing metal-carbon composites, Pt1-xNix/CNF, with a tunable Pt/Ni ratio. The composites consist of Pt1-xNix (x = 0.0-1.0) nanoparticles embedded within a carbon nanofiber (CNF) structure. The synthesis involves the spontaneous disintegration of Pt1-xNix alloys in an ethylene-containing atmosphere, resulting in the formation of CNF. The study also investigates the impact of Ni content on the activity of Pt1-xNix alloys in ethylene decomposition, revealing an increase in efficiency with higher Ni concentration. Additionally, the synthesized Pt1-xNix/CNF composites exhibit superior activity compared to the Pt/Vulcan commercial catalyst in the electrochemical hydrogen evolution reaction.