Facile Electrospinning Preparation and Up-Conversion Luminescence Performance of Y3Al5O12:Er3+, Yb3+ Nanobelts

Electrospinning technique was used to prepare $ {\text{PVP}}/\left {{\text{Y}}\left( {{\text{NO}}_{ 3} } \right)_{ 3} + {\text{Yb}}\left( {{\text{NO}}_{ 3} } \right)_{ 3} + {\text{Er}}\left( {{\text{NO}}_{ 3} } \right)_{ 3} + {\text{Al}}\left( {{\text{NO}}_{ 3} } \right)_{ 3} } \right] $ composite nanobelts and novel structures of Y₃Al₅O₁₂:Er³⁺, Yb³⁺ (denoted as YAG:Er³⁺, Yb³⁺ for short) nanobelts have been successfully fabricated after calcination of the relevant composite nanobelts at 900 °C for 8 h. YAG:Er³⁺, Yb³⁺ nanobelts were characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM) and fluorescence spectroscopy. XRD analysis indicated that YAG:Er³⁺, Yb³⁺ nanobelts were cubic in structure with space group I_a3d. SEM analysis and histograms revealed that the width of YAG:Er³⁺, Yb³⁺ nanobelts was ca. 1.8 ± 0.37 μm under the 95 % confidence level, and the thickness was ca. 81.8 nm. Up-conversion emission spectra analysis manifested that YAG:Er³⁺, Yb³⁺ nanobelts respectively emitted strong green and red emissions centering at 522, 554 and 648 nm under the excitation of a 980-nm diode laser. The green emissions were assigned to the energy levels transitions of $ ^{ 2} {\text{H}}_{ 1 1/ 2} ,^{ 4} {\text{S}}_{ 3/ 2} \to^{ 4} {\text{I}}_{ 1 5/ 2} $ of Er³⁺ ions, and the red emission originated from the energy levels transition of $ ^{ 4} {\text{F}}_{ 9/ 2} \to ^{ 4} {\text{I}}_{{{\text{l5}}/ 2}} $ of Er³⁺ ions. The up-conversion luminescence of YAG:Er³⁺, Yb³⁺ nanobelts doped with various concentrations of Yb³⁺ and Er³⁺ was studied and the optimum molar ratio of Yb³⁺ to Er³⁺ was found to be 15:1. CIE analysis demonstrated that color-tuned luminescence can be obtained by adjusting doping concentrations of Yb³⁺ and Er³⁺ ions, which could be applied in the fields of optical telecommunication and optoelectronic devices. The up-conversion luminescent mechanism and the formation mechanism of YAG:Er³⁺, Yb³⁺ nanobelts were also proposed.