TY - JOUR
T1 - One-pot template-free synthesis, growth mechanism and enhanced photocatalytic activity of monodisperse (BiO) 2CO 3 hierarchical hollow microspheres self-assembled with single-crystalline nanosheets
AU - Dong, Fan
AU - Zheng, Anmin
AU - Sun, Yanjuan
AU - Fu, Min
AU - Jiang, Boqiong
AU - Ho, Wing Kei
AU - Lee, Shuncheng
AU - Wu, Zhongbiao
PY - 2012/5/21
Y1 - 2012/5/21
N2 - This work presents a one-pot template-free synthesis, detailed characterization, growth mechanism and application of well-defined uniform monodisperse (BiO) 2CO 3 hierarchical hollow microspheres self-assembled with single-crystalline nanosheets. The synthesis was conducted by hydrothermal treatment of bismuth citrate and sodium carbonate in water. Time-dependent evolutions of phase structure, composition, and morphology were investigated systematically and revealed that the growth mechanism of such novel structures involved a unique multistep pathway. First, near amorphous particles were produced through reaction, nucleation, crystallization, and aggregation processes. Then, stacked embryos of intermediate (BiO) 4CO 3(OH) 2 microspheres with attached particles were produced due to dissolution and recrystallization. Subsequently, stacked uniform solid microspheres with small particles attached on edges were generated by the consumption of particles through Ostwald ripening. The stacked microspheres further grew to form monodisperse hierarchical microspheres with a hole in the center, like flower buds. Finally, uniform monodisperse (BiO) 2CO 3 hierarchical hollow microspheres were produced through layers splitting. The aggregation of the self-assembled nanosheets contributed to the formation of 3D hierarchical architecture containing mesopores, which is favorable for efficient reactants transport and photo-energy harvesting. Furthermore, the band gap structure of (BiO) 2CO 3 was revealed by the experimental method combined with density functional theoretical calculation. As expected, the novel (BiO) 2CO 3 hierarchical hollow microspheres exhibited enhanced photocatalytic activity due to the special hierarchical morphology, exceeding that of (BiO) 2CO 3 particles and commercial P25. The as-prepared uniform (BiO) 2CO 3 microspheres with well-defined hierarchical hollow structures are also ideal candidates for investigating their architecture-dependent performances in other areas, such as solar energy conversion, catalysis, electronics and so on.
AB - This work presents a one-pot template-free synthesis, detailed characterization, growth mechanism and application of well-defined uniform monodisperse (BiO) 2CO 3 hierarchical hollow microspheres self-assembled with single-crystalline nanosheets. The synthesis was conducted by hydrothermal treatment of bismuth citrate and sodium carbonate in water. Time-dependent evolutions of phase structure, composition, and morphology were investigated systematically and revealed that the growth mechanism of such novel structures involved a unique multistep pathway. First, near amorphous particles were produced through reaction, nucleation, crystallization, and aggregation processes. Then, stacked embryos of intermediate (BiO) 4CO 3(OH) 2 microspheres with attached particles were produced due to dissolution and recrystallization. Subsequently, stacked uniform solid microspheres with small particles attached on edges were generated by the consumption of particles through Ostwald ripening. The stacked microspheres further grew to form monodisperse hierarchical microspheres with a hole in the center, like flower buds. Finally, uniform monodisperse (BiO) 2CO 3 hierarchical hollow microspheres were produced through layers splitting. The aggregation of the self-assembled nanosheets contributed to the formation of 3D hierarchical architecture containing mesopores, which is favorable for efficient reactants transport and photo-energy harvesting. Furthermore, the band gap structure of (BiO) 2CO 3 was revealed by the experimental method combined with density functional theoretical calculation. As expected, the novel (BiO) 2CO 3 hierarchical hollow microspheres exhibited enhanced photocatalytic activity due to the special hierarchical morphology, exceeding that of (BiO) 2CO 3 particles and commercial P25. The as-prepared uniform (BiO) 2CO 3 microspheres with well-defined hierarchical hollow structures are also ideal candidates for investigating their architecture-dependent performances in other areas, such as solar energy conversion, catalysis, electronics and so on.
UR - http://www.scopus.com/inward/record.url?scp=84860356067&partnerID=8YFLogxK
U2 - 10.1039/c2ce06677g
DO - 10.1039/c2ce06677g
M3 - Journal article
SN - 1466-8033
VL - 14
SP - 3534
EP - 3544
JO - CrystEngComm
JF - CrystEngComm
IS - 10
ER -