Synthesis of Gd(III)-MOF: Dy3+ phosphor and kinetics study of its thermal decomposition

Due to their ability to form white light by mixture of blue emission and yellow emission from Dy 3+ ions, Dy 3+ -doped phosphors have attracted much attention recently. For the sake of obtaining white-emitting phosphors excited by near-UV (ultraviolet) chip, a series of Gd(III)-MOF: x Dy 3+ (Gd(III)(BTC): x Dy 3+ ) (where MOF = metal–organic framework, and BTC = 1,3,5-benzenetricarboxylate) phosphors have been prepared by hydrothermal method, and Gd(III)-MOF: 0.0125Dy 3+ is the optimal sample. When compared to that of normal Dy 3+ doped inorganic compound phosphors, some new luminescent performances inducing by Gd(III)-MOF were presented: (a) CT band is redshifted by about 26 nm and is much stronger than f → f transition band. (b) In the PL spectra, the blue emission bands have two split peaks, and the right peak is stronger than the left one. The chromaticity coordinates value of Gd(III)-MOF: 0.0125Dy 3+ indicated that the optimal sample is greenish white-emitting phosphor under UV excitation. Kinetics of thermal decomposition of the Gd(III)-MOF: 0.0125Dy 3+ was explored. Activation energies were determined by the KAS iterative method. The mechanism function of the decomposition was g ( α ) = (1 − α )^(− 1/2) − 1 determined by the Z ( α ) masterplots method, which was attributed to the chemical reaction mechanism.