Superparamagnetic behavior in chemically synthesized nanocrystalline Zn0.99Ni0.01O powders

► Synthesis of nanocrystalline Zn0.99Ni0.01O powders by autocombustion technique. ► Observation of room temperature superparamagnetic behavior in nanocrystalline Zn0.99Ni0.01O. ► Defect induced ferromagnetism and Ni-Ni antiferromagnetism exist in Zn0.99Ni0.01O nanopowders.