Synthesis And Study Of Tellurium Dioxide And Its Composite

In this paper, we dedicated to prepare and study the properties of tellurium dioxide nanoparticles(Te O2NPs), N-doped carbon dots(NCDs), Te O2/NCDs composite materials, Te O2 crystal, and upconversion luminescent materials: Te O2:Er3+/Yb3+, Te O2:Tm3+/Yb3+ porous microspheres.Te O2 NPs were successfully prepared with the modifiers of dicarboxylic amino acids, glutamic acid(Glu) and aspartic acid(Asp). They were spheres with main size distribution of 30-80 nm. The FTIR analyses proved that the Glu and Asp bound to Te O2 NPs with carboxyl groups by forming bidentate bridging and bidentate chelating, respectively. The morphology and structure of Te O2 NPs were influenced by high temperature, Te O2/NCDs compounds were prepared through one-step hydrothermal route under 180 ℃, then calcined under 600 ℃ to remove impurities(mainly carbon) to get pure Te O2 micro crystal particles.A green and facile method was developed to synthesize nitrogen doped in carbon dots(NCDs) with high photoluminescence quantum yields by hydrothermal treatment of Asp and Glu. On the basis of previous research, prepared Te O2/NCDs composite fluorescent microspheres by sodium tellurite hydrolysis in carbon solution. Carbon dots prepared by Asp hydrothermal reaction. Te O2/NCDs composites microspheres have the same fluorescence properties with NCDs and displayed preferable electrochemical characteristic in the meantime.Doped up-conversion rare earth ions and prepared Te O2:Er3+/Yb3+ with up-conversion yellow light and Te O2:Tm3+/Yb3+ with blue light porous microsphere material respectively. Observed the morphology and structure of the samples and explained the preparation mechanism. Meanwhile, researched on the properties of up-conversed luminescence and studied the luminescence mechanism...