Combustion synthesis and luminescence of monoclinic Gd2O3: Bi phosphors

Abstract

Monoclinic Gd2O3: Bi phosphors were prepared with a combustion method at an ignition temperature as low as 240–300°C using glycine as a fuel and PEG4000 as a dispersant. The samples were characterized by X-ray diffraction (XRD), photoluminescence (PL) spectroscopy and transmission electron microscope. XRD indicated that both monoclinic and cubic Gd2O3: Bi3+ phosphors could be achieved with the combustion method by adjusting the molar ratios of glycine to NO3− (G/N). Blue (430–500nm) emissions were observed with monoclinic Gd2O3: Bi3+ when excited with UV light in a wide spectrum range of 300–380nm. Its PL intensity could be improved by calcining at a higher temperature or adding appropriate amount of PEG4000. TEM images show that the product consists of aggregate of nanospheres with 50–200nm in size. Both excitation and emission spectrum of monoclinic Gd2O3: Bi phosphors match the requirement of light-conversion agent, and has a promising prospect in agriculture applications.