Yunhui Li

Synthesis and luminescent properties of uniform monodisperse YBO3:Eu3+/Tb3+ microspheres

Uniform monodisperse YBO3:Eu3+/Tb3+ microspheres have been successfully synthesized via a facile ethylene glycol-mediated solvothermal method. The crystal structure, morphology and luminescence properties of the prepared products have been characterized by X-ray diffraction, field-emission scanning electron microscopy, Fourier transform infrared spectroscopy, and photoluminescence excitation and emission spectra. It was found that the size and morphology of the products could be effectively controlled by adjusting the reaction parameters, such as reaction temperature, pH value and the amount of ethylene glycol. It could be noted that ethylene glycol plays an extremely critical role in the morphology determination. The possible growth mechanism of YBO3 microspheres was further discussed in detail on the basis of a series of time-dependent experiments. Furthermore, the luminescence properties reveal that the YBO3:Eu3+ and YBO3:Tb3+ phosphors show strong orange and green emissions under ultraviolet excitation, respectively.

Reduced Graphene‐Wrapped MnO2 Nanowires Self‐Inserted with Co3O4 Nanocages: Remarkable Enhanced Performances for Lithium‐Ion Anode Applications

A simple synthetic approach for graphene-templated nanostructured MnO2 nanowires self-inserted with Co3 O4 nanocages is proposed in this work. The Co3 O4 nanocages were penetrated in situ by MnO2 nanowires. As an anode, the as-obtained MnO2 -Co3 O4 -RGO composite exhibits remarkable enhanced performance compared with the MnO2 -RGO and Co3 O4 -RGO samples. The MnO2 -Co3 O4 -RGO electrode delivers a reversible capacity of up to 577.4 mA h g(-1) after 400 cycles at 500 mA g(-1) and the Coulombic efficiency of MnO2 -Co3 O4 -RGO is about 96 %.

Facile synthesis of Pt3Sn/graphene nanocomposites and their catalysis for electro-oxidation of methanol

A novel strategy for obtaining a high dispersion of Pt3Sn nanoparticles (NPs) on graphene is demonstrated by exploiting the intermediate phase of Sn/graphene nanocomposite as template. The results show that the Pt3Sn NPs with sizes of approximate 3–4 nm uniformly disperse on graphene surface. Electrochemical studies reveal that the Pt3Sn/graphene (50%) nanocomposites show excellent electrocatalytic activity toward methanol oxidation compared with commercial Pt/C catalysts.

A highly stable porous multifunctional Co(II) metal–organic framework showing excellent gas storage applications and interesting magnetic properties

A porous multifunctional Co(II)-metal–organic framework with large BET and Langmuir surface areas of 911.0 and 1126.8 cm3 g−1, respectively, exhibits excellent N2 (292.0 cm3 g−1), H2 (181 cm3 g−1, 1.6 wt%), and CO2 storage capacities (123 cm3 g−1, 24.3 wt%). Furthermore, it also exhibits interesting ferrimagnetic behavior.