Ligang Gai

One-pot synthesis of nitrogen-doped TiO2 nanorods with anatase/brookite structures and enhanced photocatalytic activity

Nitrogen doping in combination with a heterostructure can not only modify the band structure of TiO2 to make it more responsive to visible light, but also suppress charge recombination and lead TiO2 to have enhanced photocatalytic activity as compared to P25. Also, one-dimensional TiO2 nanostructures can serve as electron highways for efficient charge separation and, hence, increase the lifetime of charge carriers and enhance the efficiency of interfacial charge transfer to the adsorbed substrate. In this paper, a simple one-pot synthetic strategy has been designed for preparing TiO2 nanorods with good crystallinity, nitrogen doping and anatase/brookite binary structure characters, using N2H4·H2O as an in situ nitrogen doping source. The physicochemical properties of the catalysts can be tuned by simply changing the concentration ratios of N2H4·H2O to TiO2 colloids. The synergistic effect of nitrogen doping in association with a one-dimensional and anatase/brookite binary structure is suggested to account for the higher catalytic activity of the TiO2 nanorods for decomposing methyl orange and 4-chlorophenol compared to the nanoparticle counterparts under UV and/or visible light illumination.

Nitrogen-doped In2O3 nanocrystals constituting hierarchical structures with enhanced gas-sensing properties

Doping indium oxide with nitrogen species is a strategy to extend its photoresponse to the visible region and to modify its band structure, enabling the material to have potential applications in photocatalysis, optoelectronics, and sensors. In this paper, we report on a simple solvothermal synthesis method for producing nitrogen-doped indium oxide nanocrystals that are composed of hierarchical structures. The samples were characterized with XRD, Raman spectroscopy, SEM, HRTEM, FTIR, XPS, UV-vis, and photoluminescence techniques, and further tested in the role of an ethanol gas sensing material. The optical properties and the gas-sensing performance of indium oxide can be tuned by controlling the nitrogen doping. Also, the nitrogen species, resulting from the nitrogen doping, function like a surface modifier to enhance the sensitivity of the sensors that were made from the nitrogen-doped indium oxides on their exposure to ethanol gas.

Synthesis, structure and photoluminescent properties of two complexes based on iso-cyanuric acid

Two new complexes, [Cu 2 (C 3 N 3 O 3 H 2 )4]·H 2 O, I, and [Zn(C3N303H2)2(H20)4]·C 3 N 3 O 3 H 3 ·H 2 O, II, have been synthesized by the reactions of cyanuric chloride (C 3 N 3 Cl 3 ), melamine (C 3 N 6 H 6 ) with CuCl 2 ·2H 2 O and ZnCl 2 , respectively, through hydrothermal route. They were characterized by single crystal diffraction, elemental analysis, thermalgravimetry analysis. Furthermore, the photoluminescent properties of both I and II were studied. In complex (I), the Cu(II) is two coordinated in a linear fashion by two nitrogen atoms. The Zn(II) atom in complex (II) is surrounded by two nitrogen atoms and four oxygen atoms to complete a six-coordinate environment. The combination of hydrogen bonds and π····π stacking interactions extends complex (I), (II) into three-dimension architectures.