Structural, chemical and magnetic investigations of polycrystalline Zn1− x Mn x O

Abstract: Present study reports the detailed structural and magnetic, as well as chemical analysis of polycrystalline Zn1− x Mn x O (where x=0, 0.005, 0.01, 0.03, 0.05 and 0.1) samples synthesized by the high-temperature solid state reaction route. X-ray diffraction studies reveal the presence of secondary phase for higher Mn-doping concentrations (x≥0.03). Secondary phase formation having spinel structure is confirmed and reported as an evidence for the first time using transmission electron microscopy study. Chemical investigations using X-ray photoelectron spectroscopy showed the presence of Mn in two valence states. From the observed results we are of the opinion that Zn2+ ions, mainly present at or near grain boundaries, diffuse into manganese oxide to form a stable spinel phase Zn x Mn3− x O4 at or near the grain boundaries of ZnO/Zn1− x Mn x O. Magnetization measurements did not show any magnetic transition down to 5K. [Copyright &y& Elsevier]