@article{c493a69ead0c487a892a01807b7a1a61,
title = "Template-Free Synthesis and Mechanistic Study of Porous Three-Dimensional Hierarchical Uranium-Containing and Uranium Oxide Microspheres",
abstract = "A novel type of uranium-containing microspheres with an urchin-like hierarchical nano/microstructure has been successfully synthesized by a facile template-free hydrothermal method with uranyl nitrate hexahydrate, urea, and glycerol as the uranium source, precipitating agent, and shape-controlling agent, respectively. The as-synthesized microspheres were usually a few micrometers in size and porous inside, and their shells were composed of nanoscale rod-shaped crystals. The growth mechanism of the hydrothermal reaction was studied, revealing that temperature, ratios of reactants, solution pH, and reaction time were all critical for the growth. The mechanism study also revealed that an intermediate compound of 3UO3{dot operator}NH3{dot operator}5H2O was first formed and then gradually converted into the final hydrothermal product. These uranium-containing microspheres were excellent precursors to synthesize porous uranium oxide microspheres. With a suitable calcination temperature, very uniform microspheres of uranium oxides (UO2+x, U3O8, and UO3) were successfully synthesized.",
keywords = "Actinides, Oxides, Phase transitions, Porous structures, Uranium",
author = "Lin Wang and Ran Zhao and Wang, {Cong zhi} and Yuan, {Li yong} and Gu, {Zhan jun} and Xiao, {Cheng liang} and Wang, {Shu ao} and Wang, {Xin wei} and Zhao, {Yu liang} and Chai, {Zhi fang} and Shi, {Wei qun}",
note = "Funding Information: This work was supported by the Natural Science Foundation of China (Grants no. 91326202, 11305184, 11275219, 11105162, 21201166, and 21101157) and the “Strategic Priority Research program” of the Chinese Academy of Sciences (Grants no. XDA030104). The authors thank Dr. Patricia L. Bounds of the ETH-Z{\"u}rich and the IT′IS Foundation for proof-reading and editing the manuscript. Professor Peter C. Burns is highly acknowledged for his encouragement in manuscript preparation. Funding Information: This work was supported by the Natural Science Foundation of China (Grants no. 91326202, 11305184, 11275219, 11105162, 21201166, and 21101157) and the “Strategic Priority Research program” of the Chinese Academy of Sciences (Grants no. XDA030104). The authors thank Dr. Patricia L. Bounds of the ETH-Z{\"u}rich and the IT{\textquoteright}IS Foundation for proof-reading and editing the manuscript. Professor Peter C. Burns is highly acknowledged for his encouragement in manuscript preparation. Publisher Copyright: {\textcopyright} 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim",
year = "2014",
month = sep,
day = "22",
doi = "10.1002/chem.201403724",
language = "English (US)",
volume = "20",
pages = "12655--12662",
journal = "Chemistry - A European Journal",
issn = "0947-6539",
publisher = "Wiley",
number = "39",
}