Electrospinning preparation, structure, and photoluminescence properties of YBO3:EU3+ nanotubes and nanowires

A novel method, electrospinning, was explored to prepare europium-doped YBO3 nanocrystalline phosphors. Narrow and size-controllable YBO3 nanotubes and nanowires were obtained, varying from 40 to 500 nm. The average wall thickness of the nanotubes was only 5-10 nm. The structural properties were characterized by X-ray diffraction (XRD), Fourier-transform infrared absorption (FTIR), electron spin resonance (ESR), field emission scanning electron micrographs (FE-SEM), and high-resolution transmission electron micrographs (HR-TEM). The results indicate that the YBO3 nanotubes and nanowires were hexangular in phase and single crystals or polycrystalline in structure. Some surface dangling bonds caused by transition metal ions lead to a change of the coordination number of boron from +3 to +4. The photolummescent properties of the YBO3: Eu3+ nanowires and nanotubes were also characterized. It was observed that the charge-transfer excitation bands of Eu3+ in the nanowires and nanotubes blueshifted in contrast to those in bulk, because of the variation of coordination environments.