We report dynamic alternation of the redox chemistry of the Fe/ Fe couple in magnetite during high temperature water−gas shift reaction in Cu codoped Mmodified ferrite catalysts. Various hematitic solid solutions of the type Fe2O3−MxOy−CuOx with M = Cr, Ce, Ni, Co, Mn, and Zn are synthesized using the industrially economical and environmentally friendly coprecipitation method. Interestingly, Cu...