Synthesis of micro- and nanosized manganese oxides from hydrated manganese oxalates and products of their chemical modification with ethylene glycol

The reactions of ethylene glycol with manganese oxalates MnC₂O₄ · 2 H₂O and MnC₂O₄ · 3H₂O on heating in air were studied. At temperature below 100°C, ethylene glycol was found to displace water from oxalates to give a new solvate compound according to the reaction MnC₂O₄ · nH₂O + HOCH₂CH₂OH = MnC₂O₄(HOCH₂CH₂OH) + nH₂O↑. The crystals of the solvates retain the morphology of the initial oxalates, which is then inherited by the products of their thermolysis. Thus, thermolysis of MnC₂O₄ · 3H₂O and MnC₂O₄(HOCH₂CH₂OH) having quasi-unidimensional structure gave Mn₃O₄ and Mn₂O₃ nanowhiskers in air and MnO in an inert gas environment. Heating of MnC₂O₄ · nH₂O in ethylene glycol at temperatures above 100°C results in anhydrous manganese oxalate.