By using a semi-rigid tripodal ligand 5-(4-carboxybenzyloxy)isophthalic acid (HL) and lanthanide metal ions (Nd, Tb), two novel lanthanide metal-organic frameworks, namely, {[NdL(DMF)4] DMF} (), and {TbL(DMF)(HO)} (), were synthesized under mild solvothermal conditions and structurally characterized by X-ray single crystal diffraction. Compounds and are isostructural, in which L ligands linked dinuclear lanthanide metal-carboxylate units to form non-interpenetrated 3D network with (3,6)-connected topology. Luminescent investigations reveal that compound displays the near-infrared emission at room temperature, and compound can be employed as selective probe for CrO anion in aqueous solution based on luminescence quenching.
View Article and Find Full Text PDFIncorporation of semiconductor property into zeolite materials is a plausible approach to graft oxide zeolites with multifunctionality in which both electronic/optoelectronic functions and high porosity are integrated. However, creating such semiconductor zeolites, especially the ones with controllable function regulation still remains as a great synthetic challenge over the years. Hereby, we reported the first case of an interrupted chalcogenide-based zeolite-analog semiconductor with an entirely new boracite-related framework and specific sites at the interrupted section.
View Article and Find Full Text PDFThe direct synthesis of tungsten nitride (WN) nanoparticles on nitrogen-doped carbon black (N-carbon black) was achieved through facile nucleation and growth of WN nanoparticles on simultaneously generated N-carbon black under ammonia annealing. As a noble-metal-free catalyst, the WN/N-carbon black hybrid exhibited excellent performance in ORR, coupled with superior methanol tolerance and long-term stability in comparison to commercial Pt/C catalysts, through an efficient four-electron-dominant ORR process.
View Article and Find Full Text PDFThe high price of platinum (Pt)-based cathode catalysts for the oxygen reduction reaction (ORR) have slowed down the practical application of fuel cells. Thanks to their low cost, and outstanding, stable catalytic properties, titanium nitrides (TiN) are among the most promising non-precious metal electrocatalysts for replacing Pt. However, the shape-activity relationships of TiN electrocatalysts have not been well-studied or understood up to now.
View Article and Find Full Text PDFThe TiO2 nanobelt/ZnO nanorod composite photoelectrodes with flower-like and/or grass-like microstructures have been fabricated via a facile solution growth routine, just by controlling the treatment of the TiO2 nanobelt substrate. For the flower-like composite, the ZnO nanorods disperse orientationally on TiO2 nanobelt films, while for the grass-like one, ZnO nanorods grow disorderly like grass on the TiO2 nanobelt film surface. Furthermore, quasi-Fermi energy level changes of both photoelectrodes have been quantitatively characterized by the surface photovoltage based on the Kelvin probe, which clearly reveals the efficiency of photogenerated electron-hole separation.
View Article and Find Full Text PDFThe anatase TiO(2) pillar (PL)-TiO(2) nanoparticle (NP) composite is fabricated via layer-by-layer assembly. The composition of the nanostructures (i.e.
View Article and Find Full Text PDFThe TiO(2)-B nanobelt (NB)/TiO(2) nanoparticle (NP) sandwich-type structure photoelectrode, with controllable nanobelt length, has been used to fabricate high-efficiency dye-sensitized solar cells (DSSCs), which combine the advantages of the rapid electron transport in TiO(2)-B NBs and the high surface area of TiO(2) NPs. The results indicate that the sandwich-type photoelectrode achieves higher photoelectrical conversion efficiency when compared with the TiO(2) nanoparticulate electrode. Increasing the length of TiO(2)-B NBs has been demonstrated to improve the photoelectric conversion efficiency (η).
View Article and Find Full Text PDFHierarchical anatase TiO(2) porous nanopillars with high crystallinity and stability were fabricated by the following four steps: (i) synthesis of a titanium glycolate nanopillar precursor; (ii) transformation into stable nanopillars consisting of amorphous TiO(2) primary nanoparticles at low temperature; (iii) treatment with ethylenediamine aqueous solution to protect the nanopillar structure, restrain nanoparticle growth and retard phase transformation; (iv) calcination at temperatures as high as 700 degrees C to form hierarchical anatase TiO(2) porous nanopillars. The results of SEM, TEM and XRD reveal that these TiO(2) nanopillars have a porous structure, and that their length can be easily controlled by the volume ratio of ethylene glycol to tetrabutyl titanate. In addition, dye-sensitized solar-cells (DSSCs) were assembled with sandwich-structure photoanodes, which are composed of a layer of TiO(2) nanopillars sandwiched between two layers of TiO(2) nanoparticles.
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