Hongfang Jiu

Preparation and photoluminescence enhancement of Li+ and Eu3+ co-doped YPO4 hollow microspheres

Li+ and Eu3+ co-doped YPO4 hollow microspheres were successfully synthesized by a sacrificial template method using polystyrene (PS) as template. Techniques of X-ray diffraction (XRD), scanning electron microscopy (SEM), as well as transmission electron microscopy (TEM) were employed to characterize the as-synthesized sample. Furthermore, the photoluminescence (PL) characterization of the Li+ and Eu3+ co-doped YPO4 microsphere was carried out and the effects of the doping concentration of Li+ and Eu3+ active center concentration as well as calcination temperature on the PL properties were studied in detail. The results showed that the incorporation of Li+ ions into the YPO4:Eu3+ lattice could induce a remarkable improvement of the PL intensity. The highest emission intensity was observed with the compound of 5%Li+ and 5%Eu3+ co-doped YPO4, whose brightness was increased by a factor of more than 2.2 in comparison with that of the YPO4:5%Eu3+.

Controllable synthesis of Co-doped spinel LiMn2O4 nanotubes as cathodes for Li-ion batteries

Spinel Co-LiMn2O4 nanotubes have been synthesized via solid state reaction using α-MnO2 nanotubes as selft-emplates. The as-prepared powders were investigated by XRD, TEM, and galvanostatic discharge/charge analysis. The optimal doping amount was confirmed by galvanostatic charge/discharge measurements. The results indicate that about 67% of initial capacity (115 mAh/g) of LiMn2O4 nanotubes can be retained after 50 cycles. For Co-LiMn2O4 nanotubes, the initial reversible capacity is 126.6 mAh/g and 100 mAh/g can be maintained after 50 cycles. The capacitance retention rate of Co-LiMn2O4 nanotubes is as high as 79%. These results indicate that the doping Co can effectively improve circle stability and electrochemical performance of LiMn2O4 nanotubes.

Preparation of hollow core/shell CeO2@TiO2 with enhanced photocatalytic performance

In this study, hollow core/shell CeO2@TiO2 photocatalysts were prepared via precipitation-co-hydrothermal method. X-ray diffraction, transmission electron microscopy, UV−Vis diffuse reflectance spectroscopy, thermo-gravimetric–differential thermal analysis, and photoluminescence were used for the characterization of prepared photocatalysts. The synthesis variables were optimized in the photocatalytic removal of rhodamine B (rhB) as a model dye pollutants. The results showed that hollow core/shell CeO2@TiO2 exhibit a significantly enhanced photocatalytic activity in degradation of rhB under either UV or visible light irradiation. The formation of the hollow core/shell CeO2@TiO2 and the photocatalytic mechanisms under UV and visible light were also discussed.

Solvothermal synthesis of hollow Eu2O3 microspheres using carbon template-assisted method

This work presents a sol-gel carbon sphere template-assisted method of hollow Eu2O3 microspheres preparation. X-ray diffraction (XRD), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), as well as photoluminescence (PL) were used to characterise the products. The formation of hollow structure Eu2O3 microspheres can be assigned to a sol-gel carbon template. Furthermore, this work may confirm that the precursor sol-gel can be loaded onto the inner as well as the outer surface of carbon templates similarly as ions and nanocrystals. The presented method can afford a simple and efficient technique to obtain a series of hollow structure inorganic materials with high productivity.

Preparation of anatase/TiO2(B) TiO2 nanosheet for high performance of photocatalytic reduction of CO2

The biphases TiO2 nanosheet [anatase and TiO2(B)] was prepared by a solvothermal method, and characterized by FESEM, TEM, XRD, HRTEM, Raman spectrum, UV–Vis DRS and N2 adsorption–desorption. The photocatalytic performance of prepared samples was evaluated by reduction of CO2. The results revealed that the catalyst possessed a high performance of reduction CO2 to methanol. The concentration of catalyst was a crucial factor for the yield of methanol. The possible reason for high photocatalytic activity was forming a heterojunction between two crystal phases, which can promote the separation of electron–hole pairs and prolong it’s lifetime.

Solvothermal synthesis of reduced graphene oxide-Bi2S3 nanorod composites with enhanced photocatalytic activity under visible light irradiation

Reduced graphene oxide-Bi2S3 nanorod composites (RGO-Bi2S3 nanorod) are synthesized through a facile solvothermal approach. The obtained samples were characterized by powder X-ray diffraction, scanning electron microscopy, and transmission electron microscopy, Fourier transform infrared spectra, thermogravimetric analysis, and UV–visible diffuse reflectance spectroscopy. The photocatalytic activities of the samples were investigated by the degradation of rhodamine B under visible light irradiation. The results indicate that RGO-Bi2S3 nanorod exhibits an enhanced photodegradation activity than pure Bi2S3 nanorod. The enhancement in the photocatalytic performance could be attributed to the introduction of RGO sheets.

Preparation of g-C3N4/Zn2GeO4 heterojunctions with enhanced photocatalytic activity under visible light

A series of g-C3N4/Zn2GeO4 nanocomposites were fabricated by two-step solvothermal processes. The composites were characterized by transmission scanning electron microscopy, X-ray diffraction, Fourier Transform infrared spectroscopy, X-ray photoelectron spectroscopy and Ultraviolet–visible spectroscopy. The photocatalytic performance of the g-C3N4/Zn2GeO4 was investigated by degradation of RhB under visible light, of which the photocatalytic activity was much higher than that of pure Zn2GeO4.

Synthesized Hollow TiO 2 @g-C 3 N 4 Composites for Carbon dioxide Reduction Under Visible Light

The hollow TiO2@g-C3N4 composites were synthesized by a facile stirring method. The phase compositions, optical properties, and morphologies of the samples were characterized via X-ray diffraction, scanning electron microscope, transmission electron microscopy, high resolution transmission electron microscopy, fourier transform infrared spectroscopy, N2 adsorption–desorption, UV–Vis diffuse reflectance spectroscopy and Photoluminescence. The photocatalyitc performance was evaluated by reduction carbon dioxide under visible light irradiation. The results indicated that TiO2@g-C3N4 nanocomposites displayed higher photocatalytic activity compared with pure g-C3N4. The increased photocatalytic activity of TiO2@g-C3N4 nanocomposites can be attributed to facilitating the photo-induced electron–hole separation efficiency and enhancing the photo-induced electron migration.Graphical Abstract

Preparation of g-C 3 N 4 /Zn 2 GeO 4 heterojunctions with enhanced photocatalytic activity under visible light

A series of g-C3N4/Zn2GeO4 nanocomposites were fabricated by two-step solvothermal processes. The composites were characterized by transmission scanning electron microscopy, X-ray diffraction, Fourier Transform infrared spectroscopy, X-ray photoelectron spectroscopy and Ultraviolet–visible spectroscopy. The photocatalytic performance of the g-C3N4/Zn2GeO4 was investigated by degradation of RhB under visible light, of which the photocatalytic activity was much higher than that of pure Zn2GeO4.

Preparation of g-C3

A series of g-C3N4/Zn2GeO4 nanocomposites were fabricated by two-step solvothermal processes. The composites were characterized by transmission scanning electron microscopy, X-ray diffraction, Fourier Transform infrared spectroscopy, X-ray photoelectron spectroscopy and Ultraviolet–visible spectroscopy. The photocatalytic performance of the g-C3N4/Zn2GeO4 was investigated by degradation of RhB under visible light, of which the photocatalytic activity was much higher than that of pure Zn2GeO4.