Doping induced tailoring of properties in polycrystalline spinel vanadate – MnV2O4

We investigate the structural, electronic and magnetic properties of Mn1-xCuxV2O4 (0 ≤ x ≤ 0.1) to study the role of Cu in spinel vanadate MnV2O4. X-ray diffraction studies show the synthesized materials are single phase. However, X-ray photoelectron spectroscopy reveals the presence of cations in more than one valence state. The higher valence states of cations together with the desired ones confirm the presence of excess oxygen in a formula unit and non-stoichiometry increases with increasing Cu content. Further, with increasing Cu content, lattice parameters, unit cell volumes as well as different atomic separations shrink, whereas magnetic transition temperature gradually decreases and the structural transition disappears for x = 0.1. Moreover, magnetic hysteresis loops at 5 K remain unsaturated up to 6 Tesla applied field, whereas coercivity gradually increases and remanent magnetization decreases with increasing Cu content, in tandem with the increasing trend of grain size.