UVB‐emitting Gd 3+ ‐activated M 2 O 2 S (where M = La, Y) for phototherapy lamp phosphors

Gd 3 + ‐ activated oxysulphide ( M 2 O 2 S ) may be used to study Photoluminescence (PL) properties with respect to phototherapy . Gd 3 + ‐ activated phosphor materials are widely used for phototherapy lamps . The Gd 3 + ion gives characteristic Narrow-Band (NB) emissions , in particular in the ultraviolet ( UV ) light region , that are used to treat more than 50 types of skin diseases . In this paper , M 2 O 2 S oxysulphide doped with Gd 3 + was synthesized by the solid‐state flux fusion method and its down conversion spectral properties were studied as a function of different Gd 3 + concentrations . The sample was characterized by X-ray Diffraction (XRD) , Scanning Electron Microscope (SEM) , Fourier Transform Infrared Spectroscopy (FT‐IR) , and PL and the crystal structure was also studied . The lanthanum oxysulphide ( La 2 O 2 S )‐ activated Gd 3 + ion showed a sharp emission peak at 314 nm when excited at 275 nm excitation , whereas the yttrium oxysulphide ( Y 2 O 2 S )‐ activated Gd 3 + ion showed a sharp emission at 316 nm when excited by 272 nm . The effect of concentration of the Gd 3 + ion on the luminescence properties of M 2 O 2 S : Gd 3 + phosphor was also studied . These phosphor materials activated with the Gd 3 + ion may be suitable for phototherapy lamps , which are used to treat many types of skin diseases such as psoriasis , vitiligo , or scleroderma. Copyright © 2015 John Wiley & Sons, Ltd.