Room temperature Near-IR photoluminescence from ethylenediamine assisted solvo-hydrothermally grown wurtzite ZnS:Nd2O3 system

Abstract

Investigations on a single stable inorganic material capable of giving visible and IR emissions are a hot topic of research for luminescence applications. Nd2O3 embodied in ZnS microspheres with diameter ⁓3 μm (ZnS:Nd2O3 system) were synthesized by ethylenediamine assisted solvo-hydrothermal process for the first time. The material was characterized with powder XRD, EDAX, AES, Raman spectroscopy, UV–Visible spectroscopy and FESEM. Nd2O3 can be comfortably accommodated in ZnS microsphere without hindering the IR emission lines of neodymium ions. The appearance of Raman shift above 500 cm−1 in the ZnS:Nd2O3 systems confirmed the existence of ZnS in wurtzite phase. The PL spectra of Nd2O3 embodied in ZnS microspheres gives intense Nd related emission peaks in the IR region at 860, 874, 882, 986 and 905 nm (4F3/2 to 4I9/2 transition) and relatively weak emission at 1054 and 1071 nm (4F3/2 to 4I11/2 transition) along with the blue emission contributed to impurities and defects in the ZnS. ZnS microsphere combined with Nd2O3 systems was one of the novel inorganic material which can give blue emission and broad Near IR luminescence suitable for the fabrication of Near IR LED's and for biological imaging.