TY - JOUR
T1 - Mesocrystalline TiO2 nanosheet arrays with exposed {001} facets
T2 - Synthesis via topotactic transformation and applications in dye-sensitized solar cells
AU - Zhang, Yanhe
AU - Cai, Jinguang
AU - Ma, Yurong
AU - Qi, Limin
N1 - Funding Information:
This work was supported by the National Natural Science Foundation of China (Nos. 21473004 and 21673007) and the National Basic Research Program of China (No. 2013CB932601).
Publisher Copyright:
© 2017, Tsinghua University Press and Springer-Verlag Berlin Heidelberg.
PY - 2017/8/1
Y1 - 2017/8/1
N2 - A facile, fluorine-free approach for synthesizing vertically aligned arrays of mesocrystalline anatase TiO2 nanosheets with highly exposed {001} facets was developed through topotactic transformation. Unique mesocrystalline {001}-faceted TiO2 nanosheet arrays vertically aligned on conductive fluorine-doped tin oxide glass were realized through topotactic conversion from single-crystalline precursor nanosheet arrays based on lattice matching between the precursor and the anatase crystals. The morphology and microstructure of the {001}-faceted TiO2 nanosheets could be readily modulated by changing the reactant concentration and annealing temperature. Owing to enhanced dye adsorption, reduced charge recombination, and enhanced light scattering arising from the exposed {001} facets, in addition to the advantageous features of low-dimensional structure arrays (e.g., fast electron transport and efficient charge collection), the obtained TiO2 nanosheet arrays exhibited superior performance when they were used as anodes for dye-sensitized solar cells (DSSCs). Particularly, {001}-faceted TiO2 nanosheet arrays ~15 μm long annealed at 500 °C showed a power conversion efficiency of 7.51%. Furthermore, a remarkable efficiency of 8.85% was achieved for a DSSC based on double-layered TiO2 nanosheet arrays ~35 μm long, which were prepared by conversion from the precursor nanoarrays produced via secondary hydrothermal growth. [Figure not available: see fulltext.].
AB - A facile, fluorine-free approach for synthesizing vertically aligned arrays of mesocrystalline anatase TiO2 nanosheets with highly exposed {001} facets was developed through topotactic transformation. Unique mesocrystalline {001}-faceted TiO2 nanosheet arrays vertically aligned on conductive fluorine-doped tin oxide glass were realized through topotactic conversion from single-crystalline precursor nanosheet arrays based on lattice matching between the precursor and the anatase crystals. The morphology and microstructure of the {001}-faceted TiO2 nanosheets could be readily modulated by changing the reactant concentration and annealing temperature. Owing to enhanced dye adsorption, reduced charge recombination, and enhanced light scattering arising from the exposed {001} facets, in addition to the advantageous features of low-dimensional structure arrays (e.g., fast electron transport and efficient charge collection), the obtained TiO2 nanosheet arrays exhibited superior performance when they were used as anodes for dye-sensitized solar cells (DSSCs). Particularly, {001}-faceted TiO2 nanosheet arrays ~15 μm long annealed at 500 °C showed a power conversion efficiency of 7.51%. Furthermore, a remarkable efficiency of 8.85% was achieved for a DSSC based on double-layered TiO2 nanosheet arrays ~35 μm long, which were prepared by conversion from the precursor nanoarrays produced via secondary hydrothermal growth. [Figure not available: see fulltext.].
KW - dye-sensitized solar cells
KW - facets
KW - mesocrystals
KW - nanosheets
KW - nanostructure arrays
KW - titanium dioxide
KW - {001}
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U2 - 10.1007/s12274-017-1463-0
DO - 10.1007/s12274-017-1463-0
M3 - Article
AN - SCOPUS:85017660920
VL - 10
SP - 2610
EP - 2625
JO - Nano Research
JF - Nano Research
SN - 1998-0124
IS - 8
ER -