Magnetism and photoluminescence of Mn:ZnO/Mn:ZnS heterostructures

Abstract Mn:ZnO/Mn:ZnS core–shell heterostructures, in which Mn 2+ ions are incorporated into ZnO and ZnS host lattice by replacing Zn 2+ ion sites, have been synthesized by coating single-crystalline Mn:ZnO nanorods with a thin layer of Mn:ZnS nanocrystals. The heterostructures possess visible/ultraviolet photoluminescences and intrinsic room-temperature ferromagnetism. Photoluminescent spectrum exhibits enhanced ultraviolet emission of Mn:ZnO, defect-related green emission of Mn:ZnS, and strong orange emission due to 4 T 1 ( 4 G)– 6 A 1 ( 6 S) transition of Mn 2+ in ZnS. A strong ferromagnetic layer is found to exist on the surface of the Mn:ZnO core, which makes a much larger contribution to the macroscopic ferromagnetism of the heterostructures.