Structural and spectroscopic diagnosis of ZnO/SnO2 nanocomposite influenced by Eu3+

Europium doped ZnO/SnO2 nanocomposite phosphors were synthesized via room temperature co-precipitation method. In this work structural changes, optical properties and the associated photoluminescence response were investigated for different compositions of ZnO and SnO2 activated with Eu3+ ions. The prepared samples were systematically characterized by means of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy for obtaining the structural information about the prepared materials. Diffuse reflectance (DR) UV-Vis spectrometer and photoluminescence (PL) spectroscopy technique were employed for studying the optical properties of prepared materials. XRD results confirmed the presence of both phases, hexagonal ZnO as well as tetragonal SnO2 simultaneously and further using Debye Scherrer's and Hall-Williamson relations, crystallite size were estimated and it was found to be in the range of 8–14 nm. The FTIR studies revealed the presence of different stretching and bending modes of Zn–O and Sn–O with an additional stretching and bending vibration of absorbed water (O–H) molecules. FESEM images suggested that the particle size lied in the range of 50 to 70 nm, which were almost spherical in shapes. A long range multi colour emission from blue to red region was observed for the 320 nm excitation wavelength. The observed emission involved sharp emission due to 5D0→7F1 transition that corresponded to the magnetic dipole transition. The study showed that the Eu3+ doped nanocomposite was more suitable material than singly Eu3+ doped ZnO and Eu3+ doped SnO2 with enhanced opto-electronic and luminescence properties and potential applications in display devices.

(a) Photo-luminescence emission spectra for different doping concentration of Eu3+ in ZnO/SnO2 nanocomposites; (b) Plot of concentration quenching (inset); (c) Image of the phosphor excited by UV-light with excitation wavelength at 317 nm (inset)Figure optionsDownload as PowerPoint slide