Abstracts Book - IMRC 2018

• SA6-P051
OPTICAL AND STRUCTURAL CHARACTERIZATION OF ZnO Er
NANOCRYSTALS PREPARED BY SPRAY PYROLYSIS
Tetyana Torchynska 1 , Brahim El Filali 2 , Jorge Ramírez García 2 , Jose Luis Casas Espinola 1
1 Instituto Politécnico Nacional - IPN, fisica, Mexico. 2 Instituto Politécnico Nacional - IPN, UPIITA,
Mexico.
Morphology, emission and structure of ZnO:Er nanocrystal (NC) films have been
investigated by means of scanning electronic microscopy (SEM), energy
dispersive spectroscopy (EDS), X-ray diffraction (XRD) and photoluminescence
(PL) methods. ZnO:Er NC films were obtained by spray pyrolysis with different
Er-doping (0, 1, 2, 3 and 5at%) and then thermal annealed at 400 o C in ambient
air. SEM study has confirmed the nanocrystal (NC) structure of obtained ZnO
and ZnO Er films. X-Ray diffraction has revealed the wurtzite crystal structure in
ZnO and ZnO Er NCs. The XRD intensity of all XRD peaks monotonically
decreases with Er concentrations PL spectra demonstrate the near band edge
(NBE) and defect related PL bands in visible (2.0-3.0 eV) and infrared (0.80-
0.85eV) spectral ranges: The PL spectra were studied in dependence on Er atom
concentrations and at different temperatures within the range 10-300K for the
identification the optical transition responsible for the emission bands. PL and
XRD results have shown that the crystal quality of ZnO:Er NC films can be
improved at a small level of Er-doping (≤ 3at%) together with intensity enlarging
the near band edge (NBE) emission and PL bands related to the inner-shell
optical transitions in Er ions. In contrary, at high level of Er-doping (≥3at%) the
ZnO:Er crystallinity falling down, the PL intensities of NBE and Er-related PL
bands decrease, but the intensity of green PL band related to native defects
enlarges. The mechanisms of mentioned processes are discussed as well.
Acknowledgment:
The work was partially supported by CONACYT Mexico (project 258224) and by
SIP-IPN, Mexico (project 20180495).
Keywords: ZnO Er Nanocrystals, photoluminescence, X-ray diffraction
Presenting authors email: ttorch85@yahoo.com.mx