Thermodynamics of spinel synthesis with 3d-metals by solid-phase exchange in oxide-salt systems

The solid-phase exchange method is a promising direction in the synthesis of functional materials, including micro- and nanoscale ones. The mechanism and energy of reactions are determined by the exchange of parts of the molecules involved in the interaction. Solid-phase exchange with the formation of spinels in systems containing Al(SO), Cr(SO) and sulfates of a number of divalent 3d-metals with oxide compounds of lithium, sodium and potassium is considered as an object of research. Thermodynamic calculations show that the thermal effect of the reaction and the self-heating temperature in systems exceeding 1000 K are sufficient for the synthesis of spinels in the mode of a self-propagating exothermic reaction.