Structural and Magnetic Behavior of Mn Doped Zno Synthesized By Soft Chemical Route

Nanocrystalline undoped and 5% Mn doped ZnO powders are synthesized by sol-gel route using constituent nitrate and citrate precursors. The physico-chemical characterizations of powders calcined at various temperatures (400-1100 ̊C), are performed using techniques (XRD and SQUID) to study structural, nano/microstructural, and magnetic properties. XRD patterns clearly revealed the evolution of major wurtzite (ZnO) and minor non-stoichiometric defect cubic spinel phase of ZnMnO3–. Unexpectedly, the magnetic hysteresis loop with its large magnetic parameters are observed at room temperature as soon as the concentration of the minor phase is large enough. The analysis of the unusual room temperature ferromagnetic behavior is presented in this communication based on the dominant contributions of the secondary nanocrystalline non-stoichiometric defect cubic spinel phase of ZnMnO3–.