Abstract: Modulating and elevating the PL intensity of inorganic semiconductor through the co-doping of rare-earth and alkali cations is a viable approach for regulating their behavior. Here, we present a dual strategy, based on the co-doping process of Eu3+/Li+ of In2O3, at fixed 1 % concentration, that boosts the PL intensity. In1.98Eu0.02-xLixO3, (x = 0.0, 0.002, 0.004, 0.008) samples have been synthesized by a microwave hydrothermal method with a post-annealing treatment. The structural aspects, composition, morphology, and optical properties were analyzed by XRD with Rietveld refinement, Raman, FE-SEM, XPS, TEM, and PL spectroscopy. By adjusting the Eu3+/Li+ ratio, we control the PL emission intensity of the prominent 5D0→7F2 transition, as well as its variation with temperature. Remarkably, the sample In1.98Eu0.02-xLixO3 with x = 0.004 exhibits a five-fold increase in PL intensity compared to the In2O3: 1 % Eu3+. This enhanced performance is attributed to the synergy between the Li + doping and presence of oxygen vacancies. DFT calculations point out that the difference in the local atomic arrangements of the two adjacent [EuO6] and [LiO5Vo] clusters correlates with the amount the electron transfer as result of the charge compensation. These findings provide insights for controlling the PL emission intensity in practical applications.
Graphical abstract:
Author(s): Samantha CS Lemos, Marcelo Assis, Lara K Ribeiro, Pablo Serna-Gallén, Daniele de Souza, Amanda F Gouveia, Eloísa Cordoncillo, Yara G Gobato, Marisa C de Oliveira, Lourdes Gracia, Elson Longo, Renata C Lima, Juan Andrés
First published: 19/03/2025
