Synthesis of Delafossite-Type Ag(0.9)MnO(2) by the Precipitation Method at Room Temperature

[Image: see text] A delafossite-type Ag–Mn oxide was successfully synthesized using the precipitation method at room temperature. The delafossite is Ag(+)-deficient and has a chemical composition of Ag(0.9)MnO(2). Thermogravimetry of the Ag(0.9)MnO(2) delafossite revealed that on heating to 900 °C, it decomposed to Ag and Mn(2)O(3) in air and to Ag and Mn(3)O(4) under N(2). While cooling to room temperature in air, the delafossite phase reformed from Ag and Mn(3)O(4). The reversibility of the decomposition/reformation process is related to the similarity between the delafossite and spinel-type structures, both of which contain an octahedral layer. The reformation process could be used as a new synthetic route to Ag(+)-containing delafossite-type oxides.