title: Enhanced stokes and anti-stokes photoluminescence emission from LaAlO3:Nd+3 nanosized powder coated with a SiO2 shell layer.
abstract: The research on and development of materials in the field of rare-earth-ion doped nanocrystals for downconversion and up-conversion emission has been recognized to hold tremendous potential in the areas of photonic and biophotonic applications. In the present manuscript, the comprehensive results of the investigation of Stokes and anti-Stokes photoluminescence emission from the prepared LaAlO3:Nd+3 nanoparticles synthesized via the Pechini-type sol-gel method are presented and explained. The XRD diffraction peaks of the LaAlO3:Nd+3 nanoparticles can be easily assigned to the cubic-perovskite LaAlO3 structure. The FESEM image confirms the formation of approximately spherical particles within the range of 80 +/- 30 nm. The PL results showed that the LaAlO3 doped with 5% of Nd+3 ions shows the strongest emission. The core-shell structures obviously enhanced the photoluminescence intensity by suppressing the non-radiative emission and surface defects. As they yield the best PL measurement results, the LaAlO3:0.05Nd+3 nanoparticles were coated with a SiO2 shell layer, to enhance the photoluminescence emission. The mechanisms that are responsible for the photoluminescence emission process observed in the samples are discussed herein, with the help of the Nd+3 ion Dieke energy level diagram. Power dependence slope measurements were performed to identify the processes involved in the LaAlO3:Nd+3 up-conversion photoluminescence.
authors: Department of Nanomaterials Engineering and BK 21 Nano Fusion Technology Division, Pusan National University, Miryang, 627-706, Republic of Korea.
authors: Timur S
authors: TS
authors: Atabaev
authors: Zhonglie
authors: Z
authors: Piao
authors: Hyung-Kook
authors: HK
authors: Kim
authors: Yoon-Hwae
authors: YH
authors: Hwang
authors: Beomkeun
authors: B
authors: Kim