Synthesis, structure, and luminescence of 2D-dilute magnetic semiconductors:: Zn1-xMnxSe•0.5L (L = diamines)

The two-dimension dilute magnetic semiconductors (2D-DMS) Zn1-xMnxSe-0.5L (L = ethylenediamine or en, 1,3-propanediamine or pda, 1,4-butanediamine or bda, and 1,6-hexanediamine or hda) and their host compounds ZnSe.0.5L were prepared by solvothermal reaction in solvent L at 190 degreesC. The powder X-ray diffraction patterns of ZnSe.0.5L are indexed as isomorphous orthorhombic lattices, whose constants c increase monotonically from L = en to L = hda. The orthorhombic lattice in ab plane of ZnSe.0.5en is a shrunken 2D superlattice (root3a x c) of the (110) plane of hexagonal ZnSe. When Zn2+ is partly substituted by Mn2+, Zn1-xMnxSe.0.5L become 2D-DMS. Their photoluminescence (PL) spectra show strong Mn2+-related emission peaks at 2.07 eV (600 nm). The Mn content dependence of PL intensity of Zn1-xMnxSe.0.5hda is especially studied, and high intensities are obtained when x < 0.2. For x approximate to 0.2, the PL intensities of Zn1-xMnxSe.0.5L increase from L = en to L = hda, which can be attributed to the formation of Zn/Mn-N bonds and the effective energy transfer routes and radiative recombination of the 3d electron of Mn2+ within the 2D [Zn1-xMnxSe] layers.