22 results on '"Wang, Shuao"'
Search Results
2. Enhanced Xe/Kr separation via the pore size confinement effect of a microporous thorium-based metal–organic framework.
- Author
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Mi, Pinhong, Chen, Lixi, Li, Xiaoqi, Wang, Xia, Li, Guodong, Cheng, Liwei, Lu, Junhao, Zhang, Hailong, Wang, Yanlong, and Wang, Shuao
- Subjects
METAL-organic frameworks ,KRYPTON ,SEPARATION of gases ,NOBLE gases - Abstract
A three-dimensional microporous thorium-based metal–organic framework (Th-BPYDC-I) that features a suitable pore size for Xe was prepared. The pore confinement effect enables high Xe uptake (2.15 mmol g
−1 ) and good Xe/Kr selectivity (7.49). This work highlights the critical role of the size-matching rule in noble gas separation and provides an alternative option for Xe/Kr separation. [ABSTRACT FROM AUTHOR]- Published
- 2022
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3. A rare potassium-rich zirconium fluorophosphonate with high Eu3+ adsorption capacities from acidic solutions.
- Author
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Zhang, Jiarong, Chen, Long, Chen, Lanhua, Chen, Lei, Zhang, Yugang, Chen, Changlun, Chai, Zhifang, and Wang, Shuao
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ZIRCONIUM ,ADSORPTION capacity ,POTASSIUM nitrate ,SINGLE crystals ,NITRIC acid ,POTASSIUM channels - Abstract
A novel 3D potassium-containing zirconium fluorophosphonate K
2 Zr[CH2 (PO3 )2 ]F2 (SZ-8) was successfully synthesized as single crystals via a solvothermal method using a mixture of nitric acid and potassium nitrate as mineralizers. SZ-8 can adsorb 110.6 and 57 mg g−1 of Eu3+ in pH 2 and pH 1 solutions respectively, highlighting its potential remediation for radionuclides with high charges. SZ-8 not only possesses superior Eu3+ removal capacity under strongly acidic conditions, but also provides a universal synthesis strategy for crystalline zirconium phosphonates with inorganic counterions. [ABSTRACT FROM AUTHOR]- Published
- 2022
- Full Text
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4. Understanding the role of flux, pressure and temperature on polymorphism in ThB2O5.
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Hao, Yucheng, Murphy, Gabriel L., Kegler, Philip, Li, Yan, Kowalski, Piotr M., Blouin, Simon, Zhang, Yang, Wang, Shuao, Robben, Lars, Gesing, Thorsten M., and Alekseev, Evgeny V.
- Subjects
AB-initio calculations ,RIETVELD refinement ,X-ray powder diffraction ,X-ray diffraction measurement ,MOLECULAR volume - Abstract
A novel polymorph of ThB
2 O5 , denoted as β-ThB2 O5 , was synthesised under high-temperature high-pressure (HT/HP) conditions. Via single crystal X-ray diffraction measurements, β-ThB2 O5 was found to form a three-dimensional (3D) framework structure where thorium atoms are ten-fold oxygen coordinated forming tetra-capped trigonal prisms. The only other known polymorph of ThB2 O5 , denoted α, synthesised herein using a known borax, B2 O3 –Na2 B4 O7 , high temperature solid method, was found to transform to the β polymorph when exposed to conditions of 4 GPa and ∼900 °C. Compared to the α polymorph, β-ThB2 O5 has smaller molar volume by approximately 12%. Exposing a mixture of the α and β polymorphs to HT/HP conditions ex situ further demonstrated the preferred higher-pressure phase being β, with no α phase material being observed via Rietveld refinements against laboratory X-ray powder diffraction (PXRD) measurements. In situ heating PXRD measurements on α-ThB2 O5 from RT to 1030 °C indicated that α-ThB2 O5 transforms to the β variant at approximately 900 °C via a 1st order mechanism. β-ThB2 O5 was found to exist only over a narrow temperature range, decomposing above 1050 °C. Ab initio calculations using density functional theory (DFT) with the Hubbard U parameter indicated, consistent with experimental observations, that β is both the preferred phase at higher temperatures and high pressures. Interestingly, it was found by switching from B2 O3 –Na2 B4 O7 to H3 BO3 –Li2 CO3 flux using consistent high temperature solid state conditions for the synthesis of the α variant, β-ThB2 O5 could be generated. Comparison of their single crystal measurements showed this was identical to that obtained from HT/HP conditions. [ABSTRACT FROM AUTHOR]- Published
- 2022
- Full Text
- View/download PDF
5. Effective mitigation of gadolinium deposition using the bidentate hydroxypyridinone ligand Me-3,2-HOPO.
- Author
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Sun, Qiwen, Wang, Xiaomei, Shi, Cen, Guan, Jingwen, Chen, Lanhua, Wang, Yumin, Wang, Shuao, and Diwu, Juan
- Subjects
GADOLINIUM ,TRANSITION metals ,LEAD ,ARSENIC removal (Water purification) ,MAGNETIC resonance imaging ,POTENTIOMETRY ,CHELATION therapy ,LIGANDS (Chemistry) - Abstract
With the extensive usage of gadolinium-based contrast agents (GBCAs) in magnetic resonance imaging (MRI), gadolinium deposition has been observed in the brain, kidneys, liver, etc., and this is also closely related to the development of nephrogenic systemic fibrosis (NSF) in patients with renal dysfunction. Chelation, thereby promoting the elimination of deposited Gd(III), seems to be promising for alleviating these problems. Despite many ligands suitable for chelation therapy having been studied, the decorporation of transition metals (e.g. iron, copper, lead, etc.) and actinides (e.g. uranium, plutonium, etc.) has long been a primary concern, whereas the study of Gd(III) has been extremely limited. Due to their excellent metal binding abilities in vivo and therapeutic effects toward neurodegenerative diseases, bidentate hydroxypyridinone ligands are expected to be able to remove Gd(III) from the brain, kidneys, bones, and liver. Herein, the Gd(III) decorporation efficacy of a bidentate hydroxypyridinone ligand (Me-3,2-HOPO) has been evaluated. The complexation behavior between Me-3,2-HOPO and Gd(III) in solution and solid states was characterized with the assistance of potentiometric titration and X-ray diffraction techniques, respectively. Solution-based thermodynamic studies illustrate that the dominant species of complex between Gd(III) and Me-3,2-HOPO (HL) is GdL
2 + (log β120 = 11.8 (3)) at pH 7.4. The structure of the Gd–Me-3,2-HOPO crystal obtained from a room temperature reaction reveals the formation of a Gd(III) dimer that is chelated by four ligands as a result of metal ion hydration and ligand complexation. Cellular Gd(III) removal assays illustrate that Me-3,2-HOPO could effectively reduce final amounts of gadolinium by 77.6% and 66.1% from rat renal proximal tubular epithelial (NRK-52E) cells and alpha mouse liver 12 (AML-12) cells, respectively. Our current results suggest the potential of bidentate HOPO ligands as an effective approach to treat patients suffering from Gd(III) toxicity. [ABSTRACT FROM AUTHOR]- Published
- 2022
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6. Efficient neutron radiation shielding by boron–lithium imidazolate frameworks.
- Author
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Li, Zhenyu, Han, Yue, Wang, Aosong, Zhao, Dong, Fan, Longfei, He, Linwei, Zhang, Shuya, Cheng, Peng, Liu, Hanzhou, Chai, Zhifang, and Wang, Shuao
- Subjects
RADIATION shielding ,THERMAL neutrons ,NEUTRONS ,PARTICLE emissions ,NEUTRON capture ,THERMAL shielding - Abstract
Radiation protective materials are widely applied to avoid occupational hazards from either particle emissions or high-energy electromagnetic waves. Herein, we present a boron imidazolate framework (BIF) as a novel neutron shielding additive with high neutron capture cross-section elements B/Li and H. The BIF1-based epoxy resin matrix (Ep-BIF1) possesses high thermal stability and excellent resistance capacity. The neutron radiation shielding property was characterized using an Am–Be source, in which the thermal neutron shielding efficiency of Ep-BIF1 is notably higher than that of Ep-B
4 C with equal boron concentration, showing potential applications as an advanced efficient neutron radiation shielding composite. [ABSTRACT FROM AUTHOR]- Published
- 2022
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7. Ionothermal synthesis of a highly crystalline zirconium phosphate proton conductor.
- Author
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Gui, Daxiang, Zhang, Jinfeng, Wang, Xiuyuan, Wang, Chengzhen, Wang, Qin, Zhang, Yugang, Li, Hui, and Wang, Shuao
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SOLID state proton conductors ,ZIRCONIUM phosphate ,PROTON exchange membrane fuel cells ,PROTON conductivity ,ZIRCONIUM compounds ,SOLID electrolytes - Abstract
A highly crystalline one-dimensional zirconium phosphate, (NH
4 )2 [ZrF(PO4 )(HPO4 )] (ZrP-3), was facilely synthesized by the ionothermal method. The robust structure and rich hydrogen-bonded network make ZrP-3 an excellent proton conductor by having a proton conductivity higher than 10−2 S cm−1 at 90 °C and 95% RH. The remarkable stability makes ZrP-3 a promising solid electrolyte material for proton exchange membrane fuel cells. [ABSTRACT FROM AUTHOR]- Published
- 2022
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8. Extreme condition high temperature and high pressure studies of the K–U–Mo–O system.
- Author
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Murphy, Gabriel L., Kegler, Philip, Klinkenberg, Martina, Wang, Shuao, and Alekseev, Evgeny V.
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HIGH temperatures ,STRUCTURAL frames ,MOIETIES (Chemistry) ,SPACE groups ,SCANNING electron microscopy - Abstract
Herein the first examples of alkali earth uranyl molybdates synthesised using extreme conditions of high temperature and high pressure (HT/HP) methods, namely K
2 [UO2 (Mo2 O7 )2 ], K2 [(UO2 )2 (Mo(VI)4 Mo(IV)(OH)2 )O16 ], K3 [(UO2 )6 (OH)2 (MoO4 )6 (MoO3 OH)] and K5 [(UO2 )10 MoO5 O11 OH]·H2 O, are described and characterised. K2 [UO2 (Mo2 O7 )2 ] forms a monoclinic 2D layered structure in space group P21 /c that consists of interlinking Mo2 O7 dimers that link isolated UO2 2+ moieties forming [UO2 (Mo2 O7 )2 ]2− layers which are separated by K+ cations. K2 [(UO2 )2 (Mo(VI)4 Mo(IV)(OH)2 )O16 ] forms a disordered triclinic 3D framework structure in space group P1¯. The structure consists of isolated UO2 2+ moieties connected in a layered configuration via Mo(VI)O6 polyhedra of which the layers are bridged by Mo(IV)O6 polyhedra that are partially positionally disordered by charge balancing K+ and bridging Mo4+ cations. K3 [(UO2 )6 (OH)2 (MoO4 )6 (MoO3 OH)] adopts a disordered orthorhombic 3D framework structure in space group Pbcm consisting of small channels and large cavities built upon corner sharing MoO4 and UO2 2+ moieties that respectively encapsulate ordered and disordered K+ cations. K5 [(UO2 )10 MoO5 O11 OH]·H2 O forms a triclinic 3D framework structure in space group P1¯ consisting of interlinking UO6 , UO7 and MoO5 polyhedra which utilise cation–cation interactions between UO2 2+ moieties to create infinite channels parallel to the [001] direction which contain partially disordered K+ cations and H2 O molecules. A combination of single crystal X-ray diffraction, bond valence sums calculations and scanning electron microscopy with energy dispersive X-ray spectroscopic measurements was used to characterise all obtained samples in this investigation. The structures uncovered in this investigation are discussed systematically in detail with other members of the broader A+ –U–Mo–O system from the literature where the relationship between the degree of pressure applied and U/Mo ratio used during synthesis on the ability to obtain high dimensional structures via condensation and oligomerization of polyhedra is identified and discussed in detail. [ABSTRACT FROM AUTHOR]- Published
- 2020
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9. A unique uranyl framework containing uranyl pentamers as secondary building units: synthesis, structure, and spectroscopic properties.
- Author
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Zhang, Yugang, Chen, Lanhua, Guan, Jingwen, Wang, Xia, Wang, Shuao, and Diwu, Juan
- Subjects
URANYL compounds ,LASER beams ,REDSHIFT ,STRUCTURAL frames ,SPACE groups - Abstract
Two three-dimensional uranyl framework compounds consisting of 1,2,4-benzenetricarboxylic ligands and uranyl units have been synthesized under mild solvothermal conditions. Compound 1 adopts an open framework structure built from uranyl pentamers, which is a rare topology for uranyl structures. Compound 2 is constructed from UO
8 and UO7 bipyramids that are connected by the ligand to form a three-dimensional framework. As a consequence, compound 1 exhibits an unusual photoluminescence spectrum of one broad peak at 545 nm with a significant red shift compared to the typical uranyl emissive peaks as shown in the spectra of uranyl nitrate and compound 2. In addition, since compound 1 crystallizes in the noncentrosymmetric space group Cc, its secondary-harmonic generation property was measured under 1064 nm laser radiation, showing a moderate SHG signal response of 0.91 × KDP. [ABSTRACT FROM AUTHOR]- Published
- 2020
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10. Size-dependent selective crystallization using an inorganic mixed-oxoanion system for lanthanide separation.
- Author
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Lu, Huangjie, Guo, Xiaojing, Wang, Yaxing, Diefenbach, Kariem, Chen, Lanhua, Wang, Jian-Qiang, Lin, Jian, and Wang, Shuao
- Subjects
CRYSTALLIZATION ,RARE earth metals ,CRYSTALS - Abstract
A unique selective crystallization strategy based on an iodate–sulfate mixed-anion system has been developed for lanthanide separation. Periodic divergences in crystal formation energy enable simple Nd/Dy, La/Lu, Gd/Tb, La/Dy, and Nd/Lu separations through crystallization of the early lanthanides, giving rise to separation factors up to 123(5), 100(2), 2.4(2), 137(9), and 85(6), respectively. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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11. Assembly of porphyrin-based uranium organic frameworks with (3,4)-connected pto and tbo topologies.
- Author
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Shao, Lang, Zhai, Fuwan, Wang, Yanlong, Yue, Guozong, Li, Yingru, Chu, Mingfu, and Wang, Shuao
- Subjects
METAL-organic frameworks ,DENSITY functional theory ,COORDINATION compounds - Abstract
Three (3,4)-connected uranyl–organic frameworks (UOFs) with pto and tbo topologies were synthesized. The UOF with a pto net possesses a 2-fold interpenetrating network and exhibits 2D interconnected channels. The UOF with a tbo net is constructed from two types of ultralarge nanocages. All these compounds can efficiently remove large cationic dye crystal violet (CV) through a cation exchange mechanism. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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12. Structural and thermodynamic stability of uranyl–deferiprone complexes and the removal efficacy of U(vi) at the cellular level.
- Author
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Wang, Xiaomei, Ji, Guoxun, Shi, Cen, Diwu, Juan, Chen, Lanhua, Gui, Daxiang, Wan, Jianmei, Silver, Mark A., Wang, Jianqiang, and Wang, Shuao
- Subjects
PYRIDONE ,URANIUM ,X-ray diffraction - Abstract
Deferiprone (3-hydroxy-1,2-dimethyl-4(1H)-pyridone, DFP), which is a drug clinically used for removing heavy metals in vivo, was explored for its removal efficiency towards uranium. The reaction of uranyl nitrate hexahydrate with DFP at room temperature yielded the compound [(UO
2 )(H2 O)(C7 NO2 H8 )2 ]·4H2 O (1), which crystallizes from a mixed solution of methanol and water (pH = 7.0). X-ray diffraction shows that the stable complexation of uranyl occurs from the coordination of two bidentate DFP ligands perpendicular to the O=U=O unit with a fifth coordinating oxygen atom coming from one water molecule, resulting in a pentagonal bipyramidal geometry. The formation constants of uranyl and DFP complexes were measured and the species distribution diagram illustrates that UO2 L2 (94.6%) is the dominant uranyl-DFP complex in 0.1 M KCl solution at physiological pH = 7.4. The results from both crystallographic and potentiometric studies imply that the metal : ligand ratio is 1 : 2. The effectiveness of using DFP to remove uranium was examined at the cellular level, and the results suggest that it can significantly reduce the cellular uptake and increase the cellular release of U(vi) in renal proximal tubular epithelial cells (NRK-52E). [ABSTRACT FROM AUTHOR]- Published
- 2018
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13. An ingenious one-dimensional zirconium phosphonate with efficient strontium exchange capability and moderate proton conductivity.
- Author
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Huang, Guolin, Zhang, Jiarong, Chen, Lanhua, Gui, Daxiang, Zhang, Haowen, Zhang, Duo, Liu, Wei, Diwu, Juan, Chai, Zhifang, and Wang, Shuao
- Subjects
ZIRCONIUM phosphonates ,STRONTIUM ,PROTON conductivity - Abstract
A new 1-D zirconium phosphonate [(CH
3 )2 NH2 ]2 [Zr(CH2 (HPO3 )(PO3 ))2 ] (SZ-5) was synthesized via a solvothermal reaction and its single crystal structure was elucidated. SZ-5 exhibits efficient strontium exchange capability with high uptake capacity and selectivity, as further demonstrated by the radioactive Sr-90 removal from a real contaminated seawater sample with an extremely high ionic strength. In addition, the measured proton conductivity at 90 °C and 90% relative humidity (RH) is 5.65 × 10−4 S cm−1 . The efficient ion-exchange ability and the moderate proton conductivity suggest the potential applications of SZ-5 in fuel cells or in the remediation of contaminated water. [ABSTRACT FROM AUTHOR]- Published
- 2018
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14. A hydrolytically stable uranyl organic framework for highly sensitive and selective detection of Fe3+ in aqueous media.
- Author
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Liu, Wei, Xie, Jian, Zhang, Linmeng, Silver, Mark A., and Wang, Shuao
- Subjects
METAL-organic frameworks ,IRON compounds ,ACTINIDE elements ,DIMETHYLFORMAMIDE ,URANYL compounds - Abstract
We present a depleted uranium-based metal organic framework, UO
2 (C8 H3 O6 N)·DMF, that exhibits highly sensitive and selective detection towards Fe3+ ions in aqueous media with an extremely low detection limit of 6.3 ppb. This work offers insight into exploring the potential applications of actinide-based metal organic frameworks in the area of chemical sensing with intrinsic advantages of high selectivity and sensitivity. [ABSTRACT FROM AUTHOR]- Published
- 2018
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15. Metal–organic frameworks for radionuclide sequestration from aqueous solution: a brief overview and outlook.
- Author
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Xiao, Chengliang, Silver, Mark A., and Wang, Shuao
- Subjects
RADIOISOTOPES ,SEQUESTRATION (Chemistry) ,SORBENTS - Abstract
In this Frontier article, we pursue the sequestration of radionuclides from aqueous solution by using recently emerging metal–organic framework (MOF) materials. The design of MOF materials and their corresponding sorption properties towards radionuclides (
137 Cs,90 Sr,238 U,79 Se, and99 Tc) as well as their interaction mechanisms are highlighted. The present challenges and future prospects of removing radionulides with MOFs as sorbents are also demonstrated. [ABSTRACT FROM AUTHOR]- Published
- 2017
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16. Potassium uranyl borate 3D framework compound resulted from temperature directed hydroborate condensation: structure, spectroscopy, and dissolution studies.
- Author
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Xu, Xiaomei, Liu, Zhiyong, Yang, Shitong, Chen, Lanhua, Diwu, Juan, Alekseev, Evgeny V., Chai, Zhifang, Albrecht-Schmitt, Thomas E., and Wang, Shuao
- Subjects
POTASSIUM compounds ,URANYL compounds ,CONDENSATION ,CHEMICAL structure ,DISSOLUTION (Chemistry) ,COORDINATE covalent bond - Abstract
The equatorial coordination nature of the uranyl unit has resulted in only three uranyl borate 3D framework compounds reported so far formed from boric acid flux reactions conducted at 190 °C while all others are 2D layers. Here in this work, by increasing the reaction temperature to 250 °C, a new potassium uranyl borate K[(UO
2 )B6 O10 (OH)] (KUBO-4) framework compound is synthesized that shares the same layer topology with the previously reported 2D layered KUBO-1. The 3D structure of KUBO-4 is achieved by interlayer hydroborate condensation. The KUBO-4 was further characterized with single crystal XRD, SHG and fluorescence spectra, and TG/DSC measurements. A deep understanding regarding the dissolution behaviours of uranyl borate is achieved via solubility studies of the KUBO-1 and KUBO-4 performed using a combination of ICP-MS, powder XRD, and fluorescence spectroscopy techniques. The results confirm the lack of stability of borates in aqueous solutions with the presence of coordinating ligands in the environment regardless of the structure types. [ABSTRACT FROM AUTHOR]- Published
- 2016
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17. Atypical temperature-dependence of symmetry transformation observed in a uranyl phosphonate.
- Author
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Zheng, Tao, Gao, Yang, Gui, Daxiang, Chen, Lanhua, Sheng, Daopeng, Diwu, Juan, Chai, Zhifang, Albrecht-Schmitt, Thomas E., and Wang, Shuao
- Subjects
PHASE transitions ,PHOSPHONATES ,URANYL compounds ,LOW temperature physics ,METHYLAMMONIUM - Abstract
The example of phase transformation from a centrosymmetric space group at low temperature (LT) to a chiral space group at high temperature (HT) is reported, which was clearly resolved in a single-crystal-to-single-crystal manner in a 3D uranyl(vi) phosphonate compound [TMA][(UO
2 )2 (1,3-pbpH)(1,3-pbpH2 )] (1) (TMA+ = tetramethylammonium cation; 1,3-pbpH4 = 1,3-phenylenebis(phosphonic acid)). [ABSTRACT FROM AUTHOR]- Published
- 2016
- Full Text
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18. Surprising coordination for low-valent actinides resembling uranyl(vi) in thorium(iv) organic hybrid layered and framework structures based on a graphene-like (6,3) sheet topology.
- Author
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Li, Yuxiang, Weng, Zhehui, Wang, Yanlong, Chen, Lanhua, Sheng, Daopeng, Diwu, Juan, Chai, Zhifang, Albrecht-Schmitt, Thomas E., and Wang, Shuao
- Subjects
THORIUM ,METAL-organic frameworks ,SYMMETRY (Physics) ,COORDINATE covalent bond ,ACTINIDE elements - Abstract
Three thorium(iv)-based metal–organic hybrid compounds with 2D layered and 3D framework structures exhibiting graphene-like (6,3) sheet topologies were prepared with linkers with threefold symmetry. These compounds contain rare and relatively anisotropic coordination environments for low-valent actinides that are similar to those often observed for high-valent actinide ions. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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19. Centrosymmetric and chiral porous thorium organic frameworks exhibiting uncommon thorium coordination environments.
- Author
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Li, Yuxiang, Weng, Zhehui, Wang, Yanlong, Chen, Lanhua, Sheng, Daopeng, Liu, Yunhai, Diwu, Juan, Chai, Zhifang, Albrecht-Schmitt, Thomas E., and Wang, Shuao
- Subjects
THORIUM compounds ,IONIC liquids ,IMIDAZOLES ,COORDINATE covalent bond ,THERMOGRAVIMETRY - Abstract
The solvothermal reaction of thorium nitrate and tris-(4-carboxylphenyl)phosphine oxide in DMF affords a centrosymmetric porous thorium organic framework compound [Th(TPO)(OH)(H
2 O)]·8H2 O (1). In contrast, the ionothermal reaction of the same reagents in the ionic liquid 1-butyl-2,3-dimethylimidazolium chloride results in the formation of a rare example of a chiral and porous thorium organic framework compound, [C9 H17 N2 ][Th(TPO)Cl2 ]·18H2 O (2), which is derived solely from achiral starting materials. The geometries of the Th(iv) centers in compounds 1 and 2 are both atypical for low valent actinides, which can be best described as a ten-coordinate spherical sphenocorona and an irregular muffin, respectively. A large cavity of 17.5 Å (max. face to face) × 8 Å (min. face to face) with a BET surface area of 623 m2 g−1 in compound 2 is observed. The poor stability indicated by thermal gravimetric analysis and the water-resistance test for compound 2 may be due to the unique anisotropic coordination geometry for thorium. Temperature-dependent luminescence studies for both compounds indicate that the trends in the intensity vary as the Th–Th distance and the coordination environments of Th(iv) centers change. [ABSTRACT FROM AUTHOR]- Published
- 2015
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20. Design and synthesis of a chiral uranium-based microporous metal organic framework with high SHG efficiency and sequestration potential for low-valent actinides.
- Author
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Wang, Yanlong, Li, Yuxiang, Bai, Zhuanling, Xiao, Chengliang, Liu, Zhiyong, Liu, Wei, Chen, Lanhua, He, Weiwei, Diwu, Juan, Chai, Zhifang, Albrecht-Schmitt, Thomas E., and Wang, Shuao
- Subjects
CHEMICAL reactions ,SECOND harmonic generation ,ACTINIUM compounds ,SEQUESTRATION (Chemistry) ,MICROPOROSITY ,CHIRALITY - Abstract
The solvothermal reaction of [tris-(4-carboxylphenyl)phosphineoxide] (H
3 TPO) with UO2 (NO3 )2 ·6H2 O in DMF affords a uranium-based chiral, microporous, metal–organic framework compound [(CH3 )2 NH2 ][UO2 (TPO)]·4DMF·12.5H2 O (SCU-3) that exhibits the highest void volume (68.8%) and second-harmonic generation (SHG) efficiency (1.54 KDP) for an actinide compound reported to date. The combination of large channels and the coordination capabilities of P=O moieties in the structure enables SCU-3 to capture large amounts of Th(iv) from aqueous solutions, providing a new strategy for preparing heterobimetallic 5f/5f compounds, and may lead to applications in nuclear waste management. [ABSTRACT FROM AUTHOR]- Published
- 2015
- Full Text
- View/download PDF
21. A new chiral uranyl phosphonate framework consisting of achiral building units generated from ionothermal reaction: structure and spectroscopy characterizations.
- Author
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Zheng, Tao, Gao, Yang, Chen, Lanhua, Liu, Zhiyong, Diwu, Juan, Chai, Zhifang, Albrecht-Schmitt, Thomas E., and Wang, Shuao
- Subjects
CHIRALITY ,URANYL compounds ,PHOSPHONATES ,CHEMICAL reactions ,SPECTRUM analysis ,PYRIDINIUM compounds ,CHEMICAL synthesis - Abstract
The ionothermal reactions of uranyl nitrate and 1,3-pbpH
4 (1,3-pbpH4 = 1,3-phenylenebis(phosphonic acid) ligand in ionic liquids of [C4 mim][Dbp], [C4 mpyr][Br], and [Etpy][Br], respectively, afforded three new uranyl phosphonates, namely [C4 mim][(UO2 )2 (1,3-pbpH)(1,3-pbpH)·Hmim] (1), [UO2 (1,3-pbpH2 )H2 O·mpr] (2), and [Etpy][UO2 (1,3-pbpH2 )F] (3). Compound 1 exhibits a rare example of a chiral uranyl phosphonate 3D framework structure built from achiral building units of tetragonal bipyramidal uranium polyhedra and 1,3-pbp ligands. The structure adopts a network with channels extending along the b axis, which are filled with C4 mim+ and protonated 1-methylimidazole. In sharp contrast, compounds 2 & 3 both show pillared topology composed of uranyl pentagonal bipyramid polyhedra and phosphonate ligands. The layers are neutral in compound 2 with N-methylpyrrole molecules in the interlayer space, while compound 3 adopts anionic layer, and the charge is compensated with N-ethyl-pyridinium cations between the layers. Although compounds 1, 2, and 3 were synthesized under identical conditions with sole variation of the ionic liquid species, the resulting structures show a rich diversity in the local coordination environment of uranyl ions, the protonation of the phosphonate ligand, the conformation of ionic liquid ions, and the overall arrangement of the structure. All compounds were characterized by absorption, temperature dependent fluorescence, as well as infrared and Raman spectroscopies. [ABSTRACT FROM AUTHOR]- Published
- 2015
- Full Text
- View/download PDF
22. Understanding the role of flux, pressure and temperature on polymorphism in ThB2O5.
- Author
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Hao, Yucheng, Murphy, Gabriel L., Kegler, Philip, Li, Yan, Kowalski, Piotr M., Blouin, Simon, Zhang, Yang, Wang, Shuao, Robben, Lars, Gesing, Thorsten M., and Alekseev, Evgeny V.
- Subjects
- *
AB-initio calculations , *RIETVELD refinement , *X-ray powder diffraction , *X-ray diffraction measurement , *MOLECULAR volume - Abstract
A novel polymorph of ThB2O5, denoted as β-ThB2O5, was synthesised under high-temperature high-pressure (HT/HP) conditions. Via single crystal X-ray diffraction measurements, β-ThB2O5 was found to form a three-dimensional (3D) framework structure where thorium atoms are ten-fold oxygen coordinated forming tetra-capped trigonal prisms. The only other known polymorph of ThB2O5, denoted α, synthesised herein using a known borax, B2O3–Na2B4O7, high temperature solid method, was found to transform to the β polymorph when exposed to conditions of 4 GPa and ∼900 °C. Compared to the α polymorph, β-ThB2O5 has smaller molar volume by approximately 12%. Exposing a mixture of the α and β polymorphs to HT/HP conditions ex situ further demonstrated the preferred higher-pressure phase being β, with no α phase material being observed via Rietveld refinements against laboratory X-ray powder diffraction (PXRD) measurements. In situ heating PXRD measurements on α-ThB2O5 from RT to 1030 °C indicated that α-ThB2O5 transforms to the β variant at approximately 900 °C via a 1st order mechanism. β-ThB2O5 was found to exist only over a narrow temperature range, decomposing above 1050 °C. Ab initio calculations using density functional theory (DFT) with the Hubbard U parameter indicated, consistent with experimental observations, that β is both the preferred phase at higher temperatures and high pressures. Interestingly, it was found by switching from B2O3–Na2B4O7 to H3BO3–Li2CO3 flux using consistent high temperature solid state conditions for the synthesis of the α variant, β-ThB2O5 could be generated. Comparison of their single crystal measurements showed this was identical to that obtained from HT/HP conditions. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
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