abstract
In the present study, the pulsed laser ablation in water technique was used to produce chromium-doped ZnGa2O4 nanostructures from a sintered pellet target. The materials obtained mainly comprised the cubic spinel crystalline structure of ZnGa2O4 and the monoclinic beta-Ga2O3 as a minority phase (3%). Intra-ionic Cr3+ red luminescence from the ions in the spinel structure was the dominant recombination process in the bulk target and nanostructures. Overlapping of the Cr-related emitting centers was identified and the samples exhibited persistent red luminescence, which is of interest for bioimaging. Moreover, the temperature-dependent luminescence demonstrated the versatility of the nanostructures obtained, which can be further explored as temperature sensors based on the low energy shift of the zero phonon line peak positions as the temperature increased.
keywords
PERSISTENT LUMINESCENT NANOPARTICLES; PROMISING FLUORESCENT-PROBE; IN-VIVO; SPINEL OXIDES; N-LINES; SPECTRA; IONS; AFTERGLOW; DISORDER; PHOSPHOR
subject category
Chemistry; Physics
authors
Relvas, MS; Soares, MRN; Pereira, SO; Girao, AV; Costa, PM; Monteiro, T
our authors
Ana Violeta Girão
Junior Researcher
Maria da Silva Relvas
Research Fellowship
Sónia Oliveira Pereira
Research Fellowshipacknowledgements
The authors acknowledge financial support from FEDER funds through the COMPETE 2020 Programme and National Funds through FCT - Portuguese Foundation for Science and Technology under the project UID/CTM/50025/2013. We also acknowledge aid from Eng. Marta Ferro in the Materials and Ceramics Department, University of Aveiro, for allowing the TEM measurements to be performed and the cooperation of Doctor Rosario Soares for the XRD measurements. S. O. Pereira thanks I3N for grant no. BPD/UI96/5808/2017 and A. V. Girao is thankful for post-doctoral grant no. BPD/UI50/4119/2016. STEMEDS microscopy analysis was supported by RNME-Pole University of Aveiro FCT Project REDE/1509/RME/2005.