Highly matched spectrum needed for photosynthesis in Ce3+/Er3+/Yb3+ tri-doped oxyfluoride glass ceramics

Abstract

A series of oxyfluoride glass ceramics containing CaF2 nano-crystals tri-doped with Ce3+/Er3+/Yb3+ ions were prepared by high temperature melting method and subsequent heat treatment. The structural properties were examined by X-ray diffraction measurements. The absorption, excitation, and emission spectra of the glass ceramics were investigated. Difference in erbium emission spectra between glass and glass ceramics had been studied. The emission bands originating from the 4F9/2 state of Er3+ were enhanced when the CaF2 nano-crystal created. By down-converting the ultraviolet wavelength region (280∼400 nm) light and up-converting the near-infrared wavelength region (900∼1100 nm) light, the glass ceramics can also emit strong reddish orange emission. The emission spectra consisting of bluish violet (400∼500 nm) and reddish orange (640∼680 nm) bands match well with the action spectrum of photosynthesis and absorption spectra of chlorophylls. Our materials will be favored to promote the development of glass greenhouses for green plant.