η‐Carbides (Co, Mo, or W) Nanoparticles from Octacyanometalates Precursors‐Based Network

Abstract This paper describes a simple, two‐steps chemical pathway to obtain bimetallic carbide nanoparticles (NPs) of general formula MxM″yC, also called η‐carbides. This process allows for a control of the chemical composition of metals present in the carbides (M = Co and M″ = Mo or W). The first step involves the synthesis of a precursor consisting of a network of octacyanometalates. The second step consists in a thermal degradation of the previously obtained octacyanometalates networks under neutral atmosphere (Ar or N₂). It is shown that this process results in the formation of carbide NPs with diameter of ≈ 5nm, and the stoichiometries Co₃M’₃C, Co₆M’₆C, Co₂M’₄C for the CsCoM’ systems.