Hydrothermal synthesis of SrCO3:Eu3+/Tb3+ microneedles and their luminescence properties

SrCO3:Eu3+/Tb3+ microneedles that grow along the a-axis were successfully prepared through a large-scale and facile hydrothermal method without any template and further annealing treatment. X-ray diffraction (XRD), scanning electron microscopy (SEM), and photoluminescence (PL) spectra as well kinetic decays, were used to characterize the samples. The preferential growth along a-axis for SrCO3:Eu3+/Tb3+ microneedles has been proposed through analysis of the XRD patterns of samples obtained at different hydrothermal treatment time. Under ultraviolet excitation, the SrCO3:Eu3+ and SrCO3:Tb3+ microneedle samples show a strong red and green emission corresponding to the 5D0–7FJ (J=1, 2, 3, 4) transitions of Eu3+ and the 5D4–7FJ (J=6, 5, 4, 3) transitions of Tb3+, respectively, which have potential applications in lighting fields.