The Influence of Mechanochemical Activation on the Properties of a Double Complex Salt [Co(NH3)6][Fe(CN)6] and Its Thermolysis Products

Double complex salts (DCSs) of the composition [Co(NH3)6][Fe(CN)6] are a promising precursor for the preparation of catalysts for the hydrogenation of carbon oxides (CO and CO2) by Fischer–Tropsch synthesis. The specific surface area is an important parameter for catalysts. Our article investigates the influence of mechanochemical activation (MCA) on this DCS in order to determine the conditions for obtaining the largest specific surface area of the intermetallic compound, a product of the DCS thermolysis. In this work, the effect of MCA on the physicochemical properties of the DCS [Co(NH3)6][Fe(CN)6] and the products of its thermal decomposition in an argon atmosphere were investigated. It was shown that MCA leads to partial reduction of Fe+3 to Fe+2, changes in the coordination of ammonia, amorphization of the structure and a decrease in the thermal stability of DCS. Thermolysis at 650 °C of samples subjected to MCA for 10 min results in the formation of nanocrystalline intermetallic compound Co0.5Fe0.5. The results demonstrate the potential of using MCA to control the properties of functional materials based on DCS.