Controlled synthesis and near-infrared luminescence of LaOBr:Nd3+ nanofibers and nanobelts.

: LaOBr:Nd(3+) nanofibers and nanobelts were synthesized for the first time via calcinating the electrospun PVP/[La(NO3)3 + Nd(NO3)3 + NH4Br] composites. X-ray diffraction (XRD) analysis revealed that LaOBr:Nd(3+) nanofibers and nanobelts are tetragonal in structure with the space group of P4/nmm. The morphologies and sizes of LaOBr:Nd(3+) nanostructures were investigated by scanning electron microscope (SEM). The mean diameter of the LaOBr:Nd(3+) nanofibers is 192.41 ± 18.97 nm. The width and thickness of the LaOBr:Nd(3+) nanobelts are 5.50 ± 0.48 μm and 112 nm, respectively. Under the excitation of 532-nm laser, LaOBr:Nd(3+) nanostructures exhibit the characteristic emissions of predominant peaks at 922, 1072 and 1345 nm, attributed to (4)F3/2 --> (4)I9/2, (4)F3/2 --> (4)I11/2 and (4)F3/2 --> (4)I13/2 energy levels transitions of Nd(3+) ions, respectively. The optimum doping molar concentration of the Nd(3+) ions in the LaOBr:Nd(3+) nanofibers is 1.0%. Interestingly, we found that the luminescence intensity of nanobelts is obviously greater than that of the nanofibers for LaOBr:Nd(3+) under the same measuring conditions. The formation mechanisms of LaOBr:Nd(3+) nanofibers and nanobelts were also proposed.