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One-dimensional hierarchically superstructured metal-doped titanate and TiO2 materials with coated-nanosheet and interconnected meso-/macropores have been successfully constructed via a general strategy based on the self-evolution of building blocks. The as-fabricated superstructured TiO2-based fibers exhibited remarkable stable cycling performance at a high current rate (5C) in lithium–sulfur (Li–S) batteries. [ABSTRACT FROM AUTHOR]

Design and fabrication of hierarchically porous inorganic fibres holds exciting implications for applications in catalysis, separation, and energy devices. In this article, we present a general phase separation strategy for the fabrication of TiO2–SiO2 fibres with hierarchical pores via a typical electrospinning procedure. The porous hierarchy of the as-fabricated products and the possible formation mechanism have been investigated in detail. The results confirmed that the hydrophilic–hydrophobic repulsion between the PVP@TBT@TEOS 3D network complex and the solvent, the hydrolysis and polycondensation of inorganic alkoxides, and the slow solvent evaporation during the process of electrospinning may be responsible for the phase separation, leading to the formation of macropores in the fibres. The obtained hierarchically macro-/mesoporous TiO2–SiO2 fibres exhibited amazing structure stability even at a high calcination temperature of 850 °C. The current work may guide the further design of functional inorganic fibres with controllable hierarchical porous structures. [ABSTRACT FROM AUTHOR]

In this article, we describe a general strategy, which combines electrospinning and hydrothermal processes, for the facile fabrication of one-dimensional hollow and solid porous titania (1DHP-TiO2 and 1DSP-TiO2). Amorphous TiO2 fibres were first fabricated by a conventional electrospinnning method and then used as precursors and templates for the subsequent hydrothermal reaction. Fluoride-mediated chemically induced self-transformation (CIST) was proposed to account for the formation of the hollow and solid porous structures. By controlling the parameters of the processes (i.e. porosity and diameter of the amorphous precursors, type of the mediated reactants), titania with tunable wall thickness and inner structures could be selectively fabricated. Besides, the obtained 1DHP-TiO2 and 1DSP-TiO2 exhibited good thermal stability. The organic residues and trace amounts of Na ions in 1DHP-TiO2 and 1DSP-TiO2 may act as stabilizers to raise the phase transformation temperature. Through this current general strategy based on CIST, it is expected that more functional 1D hollow and solid porous inorganic materials for advanced applications can be designed. [ABSTRACT FROM AUTHOR]

The design of one-dimensional titania with tunable structural hierarchy holds exciting implications for applications such as optoelectronics, sensing and catalysis. Here, we report a general precursor strategy for one-dimensional titania with surface nanoprotrusion and tunable hierarchical structures realized via a titanate route using electrospun titania fibers as precursors. One-dimensional hierarchical hollow titanate (1D-HHT) was first fabricated under mild alkaline hydrothermal conditions from electrospun amorphous TiO2 precursors. The time-dependent evolution of 1D-HHT has been investigated in detail. The concerted effect of alkaline etching and Ostwald ripening is responsible for the surface nanoprotrusion and modulation of structural hierarchy. Anatase TiO2 with the same hierarchical structures can be obtained using controlled calcination. The as-fabricated one-dimensional titania with varying levels of structural hierarchy exhibits about 1.3–1.5 times higher power conversion efficiency than commercial P25 as a photoanode material for dye-sensitized solar cells (DSSCs). The current work may be extended for more functional TiO2-based materials with tunable structural hierarchy and could widen the application range of electrospinning technology for one-dimensional hierarchical structures. [ABSTRACT FROM AUTHOR]