共查询到20条相似文献,搜索用时 15 毫秒
1.
Dr. Qiu‐Feng Lü Jia‐Yin Zhang Zhi‐Wei He 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(51):16571-16579
Electroconductive poly(N‐butylaniline)–lignosulfonate (PBA–LS) composite nanospheres were prepared in a facile way by in situ, unstirred polymerization of N‐butylaniline with lignosulfonate (LS) as a dispersant and dopant. The LS content was used to optimize the size, structure, electroconductivity, solubility, and silver ion adsorptive capacity of the PBA–LS nanospheres. Uniform PBA–LS10 nanospheres with a minimal mean diameter of 375 nm and high stability were obtained when the LS content was 10 wt %. The PBA–LS10 nanospheres possess an increased electroconductivity of 0.109 S cm?1 compared with that of poly(N‐butylaniline) (0.0751 S cm?1). Furthermore, the PBA–LS10 nanospheres have a maximal silver‐ion sorption capacity of 815.0 mg g?1 at an initial silver ion concentration of 50 mmol L ?1 (25 °C for 48 h), an enhancement of 70.4 % compared with PBA. Moreover, a sorption mechanism of silver ions on the PBA–LS10 nanospheres is proposed. TEM and wide‐angle X‐ray diffraction results showed that silver nanoparticles with a diameter size range of 6.8–55 nm was achieved after sorption, indicating that the PBA–LS10 nanospheres had high reductibility for silver ions. 相似文献
2.
Souvik Pal Dr. Asamanjoy Bhunia Dr. Partha P. Jana Subarna Dey Dr. Jens Möllmer Prof. Dr. Christoph Janiak Dr. Hari Pada Nayek 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(7):2789-2792
A microporous La–metal‐organic framework (MOF) has been synthesized by the reaction of La(NO3)3 ? 6 H2O with a ligand 4,4′,4′′‐s‐triazine‐1,3,5‐triyltri‐p‐aminobenzoate (TATAB) featuring three carboxylate groups. Crystal structure analysis confirms the formation of 3D MOF with hexagonal micropores, a Brunauer–Emmett—Teller (BET) surface area of 1074 m2 g?1 and high thermal and chemical stability. The CO2 adsorption capacities are 76.8 cm3 g?1 at 273 K and 34.6 cm3 g?1 at 293 K, a highest measured CO2 uptake for a Ln–MOFs. 相似文献
3.
Kinetically Controlled Assembly of Nitrogen‐Doped Invaginated Carbon Nanospheres with Tunable Mesopores
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Yang Liu Dr. Hongwei Zhang Owen Noonan Chun Xu Dr. Yuting Niu Yannan Yang Prof. Liang Zhou Dr. Xiaodan Huang Prof. Chengzhong Yu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(42):14962-14967
Mesoporous hollow carbon nanospheres (MHCS) have been extensively studied owning to their unique structural features and diverse potential applications. A surfactant‐free self‐assembly approach between resorcinol/formaldehyde and silicon alkoxide has emerged as an important strategy to prepare MHCS. Extending such a strategy to other substituted phenols to produce heterogeneous‐atom‐doped MHCS remains a challenge due to the very different polymerization kinetics of various resins. Herein, we report an ethylenediamine‐assisted strategy to control the cooperative self‐assembly between a 3‐aminophenol/formaldehyde resin and silica templates. Nitrogen‐doped mesoporous invaginated carbon nanospheres (N‐MICS) with an N content of 6.18 at %, high specific surface areas (up to 1118 m2 g?1), large pore volumes (2.47 cm3 g?1), and tunable mesopores (3.7–11.1 nm) have been prepared. When used as electrical double‐layer supercapacitors, N‐MICS show a high capacitance of 261 F g?1, an outstanding cycling stability (≈94 % capacitance retention after 10 000 cycles), and a good rate performance. 相似文献
4.
Biomass‐Derived Porous Carbon with Micropores and Small Mesopores for High‐Performance Lithium–Sulfur Batteries
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Kai Yang Prof. Qiuming Gao Yanli Tan Weiqian Tian Weiwei Qian Lihua Zhu Chunxiao Yang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(10):3239-3244
Biomass‐derived porous carbon BPC‐700, incorporating micropores and small mesopores, was prepared through pyrolysis of banana peel followed by activation with KOH. A high specific BET surface area (2741 m2 g?1), large specific pore volume (1.23 cm3 g?1), and well‐controlled pore size distribution (0.6–5.0 nm) were obtained and up to 65 wt % sulfur content could be loaded into the pores of the BPC‐700 sample. When the resultant C/S composite, BPC‐700‐S65, was used as the cathode of a Li–S battery, a large initial discharge capacity (ca. 1200 mAh g?1) was obtained, indicating a good sulfur utilization rate. An excellent discharge capacity (590 mAh g?1) was also achieved for BPC‐700‐S65 at the high current rate of 4 C (12.72 mA cm?2), showing its extremely high rate capability. A reversible capacity of about 570 mAh g?1 was achieved for BPC‐700‐S65 after 500 cycles at 1 C (3.18 mA cm?2), indicating an outstanding cycling stability. 相似文献
5.
Controlled Synthesis of N‐Doped Carbon Nanospheres with Tailored Mesopores through Self‐Assembly of Colloidal Silica
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Gang Wang Prof. Yuhan Sun Prof. Debao Li Dr. Hai‐Wei Liang Dr. Renhao Dong Prof. Xinliang Feng Prof. Klaus Müllen 《Angewandte Chemie (International ed. in English)》2015,54(50):15191-15196
Limited strategies have been established to prepare monodisperse mesoporous carbon nanospheres (MCNs) with tailored pore sizes. In this work, a method is reported to synthesize MCNs by combining polymerization of aniline with co‐assembly of colloidal silica nanoparticles. The controlled self‐assembly behavior of colloidal silica enables the formation of uniform composite nanospheres and convenient modulation over mesopores. After carbonization and removal of sacrificial templates, the resultant MCNs possess tunable mesopores (7–42 nm) and spherical diameters (90–300 nm), as well as high surface area (785–1117 m2 g?1), large pore volume (1.46–2.01 cm3 g?1) and abundant nitrogen moieties (5.54–8.73 at %). When serving as metal‐free electrocatalysts for the oxygen reduction reaction (ORR), MCNs with an optimum pore size of 22 nm, compared to those with 7 and 42 nm, exhibit the best ORR performance in alkaline medium. 相似文献
6.
Magnetic Properties of a Single‐Molecule Lanthanide–Transition‐Metal Compound Containing 52 Gadolinium and 56 Nickel Atoms
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Da‐Peng Liu Xin‐Ping Lin Hui Zhang Xiu‐Ying Zheng Dr. Gui‐Lin Zhuang Prof. Dr. Xiang‐Jian Kong Prof. Dr. La‐Sheng Long Prof. Dr. Lan‐Sun Zheng 《Angewandte Chemie (International ed. in English)》2016,55(14):4532-4536
Monodisperse metal clusters provide a unique platform for investigating magnetic exchange within molecular magnets. Herein, the core–shell structure of the monodisperse molecule magnet of [Gd52Ni56(IDA)48(OH)154(H2O)38]@SiO2 ( 1 a @SiO2) was prepared by encapsulating one high‐nuclearity lanthanide–transition‐metal compound of [Gd52Ni56(IDA)48(OH)154(H2O)38]?(NO3)18?164 H2O ( 1 ) (IDA=iminodiacetate) into one silica nanosphere through a facile one‐pot microemulsion method. 1 a @SiO2 was characterized using transmission electron microscopy, N2 adsorption–desorption isotherms, and inductively coupled plasma‐atomic emission spectrometry. Magnetic investigation of 1 and 1 a revealed J1=0.25 cm?1, J2=?0.060 cm?1, J3=?0.22 cm?1, J4=?8.63 cm?1, g=1.95, and z J=?2.0×10?3 cm?1 for 1 , and J1=0.26 cm?1, J2=?0.065 cm?1, J3=?0.23 cm?1, J4=?8.40 cm?1 g=1.99, and z J=0.000 cm?1 for 1 a @SiO2. The z J=0 in 1 a @SiO2 suggests that weak antiferromagnetic coupling between the compounds is shielded by silica nanospheres. 相似文献
7.
Jingjuan Liu Yi Zhou Zhen Xie Yang Li Yunpeng Liu Jie Sun Yanhang Ma Osamu Terasaki Long Chen 《Angewandte Chemie (International ed. in English)》2020,59(3):1081-1086
A conjugated copper(II) catecholate based metal–organic framework (namely Cu‐DBC) was prepared using a D2‐symmetric redox‐active ligand in a copper bis(dihydroxy) coordination geometry. The π‐d conjugated framework exhibits typical semiconducting behavior with a high electrical conductivity of ca. 1.0 S m?1 at room temperature. Benefiting from the good electrical conductivity and the excellent redox reversibility of both ligand and copper centers, Cu‐DBC electrode features superior capacitor performances with gravimetric capacitance up to 479 F g?1 at a discharge rate of 0.2 A g?1. Moreover, the symmetric solid‐state supercapacitor of Cu‐DBC exhibits high areal (879 mF cm?2) and volumetric (22 F cm?3) capacitances, as well as good rate capability. These metrics are superior to most reported MOF‐based supercapacitors, demonstrating promising applications in energy‐storage devices. 相似文献
8.
Dr. Fei‐Fei Zhang Dr. Gang Huang Xu‐Xu Wang Dr. Yu‐Ling Qin Dr. Xin‐Chuan Du Dong‐Ming Yin Fei Liang Prof. Li‐Min Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(52):17523-17529
Core–shell hierarchical porous carbon spheres (HPCs) were synthesized by a facile hydrothermal method and used as host to incorporate sulfur. The microstructure, morphology, and specific surface areas of the resultant samples have been systematically characterized. The results indicate that most of sulfur is well dispersed over the core area of HPCs after the impregnation of sulfur. Meanwhile, the shell of HPCs with void pores is serving as a retard against the dissolution of lithium polysulfides. This structure can enhance the transport of electron and lithium ions as well as alleviate the stress caused by volume change during the charge–discharge process. The as‐prepared HPC‐sulfur (HPC‐S) composite with 65.3 wt % sulfur delivers a high specific capacity of 1397.9 mA h g?1 at a current density of 335 mA g?1 (0.2 C) as a cathode material for lithium–sulfur (Li‐S) batteries, and the discharge capacity of the electrode could still reach 753.2 mA h g?1 at 6700 mA g?1 (4 C). Moreover, the composite electrode exhibited an excellent cycling capacity of 830.5 mA h g?1 after 200 cycles. 相似文献
9.
Dr. Marisa Rico‐Santacruz Dr. Elena Serrano Dr. Giuseppe Marcì Dr. Elisa I. García‐López Dr. Javier García‐Martínez 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(50):18338-18344
Mesoporous titania–organosilica nanoparticles comprised of anatase nanocrystals crosslinked with organosilica moieties have been prepared by direct co‐condensation of a titania precursor, tetrabuthylortotitanate (TBOT), with two organosilica precursors, 1,4‐bis(triethoxysilyl) benzene (BTEB) and 1,2‐bis(triethoxysilyl) ethane (BTEE), in mild conditions and in the absence of surfactant. These hybrid materials show both high surface areas (200–360 m2 g?1) and pore volumes (0.3 cm3 g?1) even after calcination, and excellent photoactivity in the degradation of rhodamine 6G and in the partial oxidation of propene under UV irradiation, especially after the calcination of the samples. During calcination, there is a change in the TiIV coordination and an increase in the content of Si?O?Ti moieties in comparison with the uncalcined materials, which seems to be responsible for the enhanced photocatalytic activity of hybrid titania–silica materials as compared to both uncalcined samples and the control TiO2. 相似文献
10.
Strong Lithium Polysulfide Chemisorption on Electroactive Sites of Nitrogen‐Doped Carbon Composites For High‐Performance Lithium–Sulfur Battery Cathodes
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Dr. Jiangxuan Song Mikhail L. Gordin Dr. Terrence Xu Shuru Chen Zhaoxin Yu Dr. Hiesang Sohn Dr. Jun Lu Dr. Yang Ren Dr. Yuhua Duan Prof. Donghai Wang 《Angewandte Chemie (International ed. in English)》2015,54(14):4325-4329
Despite the high theoretical capacity of lithium–sulfur batteries, their practical applications are severely hindered by a fast capacity decay, stemming from the dissolution and diffusion of lithium polysulfides in the electrolyte. A novel functional carbon composite (carbon‐nanotube‐interpenetrated mesoporous nitrogen‐doped carbon spheres, MNCS/CNT), which can strongly adsorb lithium polysulfides, is now reported to act as a sulfur host. The nitrogen functional groups of this composite enable the effective trapping of lithium polysulfides on electroactive sites within the cathode, leading to a much improved electrochemical performance (1200 mAh g?1 after 200 cycles). The enhancement in adsorption can be attributed to the chemical bonding of lithium ions by nitrogen functional groups in the MNCS/CNT framework. Furthermore, the micrometer‐sized spherical structure of the material yields a high areal capacity (ca. 6 mAh cm?2) with a high sulfur loading of approximately 5 mg cm?2, which is ideal for practical applications of the lithium–sulfur batteries. 相似文献
11.
Polymerization under Hypersaline Conditions: A Robust Route to Phenolic Polymer‐Derived Carbon Aerogels
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Zhi‐Long Yu Guan‐Cheng Li Dr. Nina Fechler Ning Yang Zhi‐Yuan Ma Xin Wang Prof. Dr. Markus Antonietti Prof. Dr. Shu‐Hong Yu 《Angewandte Chemie (International ed. in English)》2016,55(47):14623-14627
Polymer‐derived carbon aerogels can be obtained by direct polymerization of monomers under hypersaline conditions using inorganic salts. This allows for significantly increased mechanical robustness and avoiding special drying processes. This concept was realized by conducting the polymerization of phenol–formaldehyde (PF) in the presence of ZnCl2 salt. Afterwards, the simultaneous carbonization and foaming process conveniently converts the PF monolith into a foam‐like carbon aerogel. ZnCl2 plays a key role, serving as dehydration agent, foaming agent, and porogen. The carbon aerogels thus obtained are of very low density (25 mg cm?3), high specific surface area (1340 m2 g?1), and have a large micro‐ and mesopore volume (0.75 cm3 g?1). The carbon aerogels show very promising potential in the separation/extraction of organic pollutants and for energy storage. 相似文献
12.
Herein, we report a facile and “green” synthetic route for the preparation of Ge@C core–shell nanocomposites by using a low‐cost Ge precursor. Field‐emission scanning electron microscopy and transmission electron microscopy analyses confirmed the core–shell nanoarchitecture of the Ge@C nanocomposites, with particle sizes ranging from 60 to 100 nm. Individual Ge nanocrystals were coated by a continuous carbon layer, which had an average thickness of 2 nm. When applied as an anode materials for lithium‐ion batteries, the Ge@C nanocomposites exhibited a high initial discharge capacity of 1670 mAh g?1 and superior rate capability. In particular, Ge@C nanocomposite electrodes maintained a reversible capacity of 734 mAh g?1 after repeated cycling at a current density of 800 mA g?1 over 100 cycles. 相似文献
13.
Ya‐Pan Wu Jun‐Wu Tian Shan Liu Bo Li Jun Zhao Lu‐Fang Ma Dong‐Sheng Li Ya‐Qian Lan Xianhui Bu 《Angewandte Chemie (International ed. in English)》2019,58(35):12185-12189
Embedding cubane [M4(OH)4] (M=Ni, Co) clusters within the matrix of metal–organic frameworks (MOFs) is a strategy to develop materials with unprecedented synergistic properties. Herein, a new material type based on the pore‐space partition of the cubic primitive minimal‐surface net (MOF‐14‐type) has been realized. CTGU‐15 made from the [Ni4(OH)4] cluster not only has very high BET surface area (3537 m2 g?1), but also exhibits bi‐microporous features with well‐defined micropores at 0.86 nm and 1.51 nm. Furthermore, CTGU‐15 is stable even under high pH (0.1 m KOH), making it well suited for methanol oxidation in basic medium. The optimal hybrid catalyst KB&CTGU‐15 (1:2) made from ketjen black (KB) and CTGU‐15 exhibits an outstanding performance with a high mass specific peak current of 527 mA mg?1 and excellent peak current density (29.8 mA cm?2) at low potential (0.6 V). The isostructural cobalt structure (CTGU‐16) has also been synthesized, further expanding the application potential of this material type. 相似文献
14.
Fluorocarbon Separation in a Thermally Robust Zirconium Carboxylate Metal–Organic Framework
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Fluorocarbons have important applications in industry, but are environmentally unfriendly, and can cause ozone depletion and contribute to the global warming with long atmospheric lifetimes and high global warming potential. In this work, the metal–organic framework UiO‐66(Zr) is demonstrated to have excellent performance characteristics to separate fluorocarbon mixtures at room temperature. Adsorption isotherm measurements of UiO‐66(Zr) display high fluorocarbon sorption uptakes of 5.0 mmol g?1 for R22 (CHClF2), 4.6 mmol g?1 for R125 (CHF2CF3), and 2.9 mmol g?1 for R32 (CH2F2) at 298 K and 1 bar. Breakthrough data obtained for binary (R22/R32 and R32/R125) and ternary (R32/R125/R134a) mixtures reveal high selectivities and capacities of UiO‐66(Zr) for the separation and recycling of these fluorocarbon mixtures. Furthermore, the UiO‐66(Zr) saturated with R22 and R125 can be regenerated at temperatures as low as 120 °C with excellent desorption–adsorption cycling stabilities. 相似文献
15.
Lei Ye Meng Liao Tiancheng Zhao Hao Sun Yang Zhao Xuemei Sun Bingjie Wang Huisheng Peng 《Angewandte Chemie (International ed. in English)》2019,58(47):17054-17060
Despite efforts to stabilize sodium metal anodes and prevent dendrite formation, achieving long cycle life with high areal capacities remains difficult owing to a combination of complex failure modes that involve retardant uneven sodium nucleation and subsequent dendrite formation. Now, a sodiophilic interphase based on oxygen‐functionalized carbon nanotube networks is presented, which concurrently facilitates a homogeneous sodium nucleation and a dendrite‐free, lateral growth behavior upon recurring sodium plating/stripping processes. This sodiophilic interphase renders sodium anodes with an ultrahigh capacity of 1078 mAh g?1 (areal capacity of 10 mAh cm?2), approaching the theoretical capacity of 1166 mAh g?1 of pure sodium, as well as a long cycle life up to 3000 cycles. Implementation of this anode allows for the construction of a sodium–air battery with largely enhanced cycling performance owing to the oxygen functionalization‐mediated, dendrite‐free sodium morphology. 相似文献
16.
Qiang Jiang Peixun Xiong Jingjuan Liu Zhen Xie Qinchao Wang Xiao‐Qing Yang Enyuan Hu Yu Cao Jie Sun Yunhua Xu Long Chen 《Angewandte Chemie (International ed. in English)》2020,59(13):5273-5277
Metal–organic framework cathodes usually exhibit low capacity and poor electrochemical performance for Li‐ion storage owing to intrinsic low conductivity and inferior redox activity. Now a redox‐active 2D copper–benzoquinoid (Cu‐THQ) MOF has been synthesized by a simple solvothermal method. The abundant porosity and intrinsic redox character endow the 2D Cu‐THQ MOF with promising electrochemical activity. Superior performance is achieved as a Li‐ion battery cathode with a high reversible capacity (387 mA h g?1), large specific energy density (775 Wh kg?1), and good cycling stability. The reaction mechanism is unveiled by comprehensive spectroscopic techniques: a three‐electron redox reaction per coordination unit and one‐electron redox reaction per copper ion mechanism is demonstrated. This elucidatory understanding sheds new light on future rational design of high‐performance MOF‐based cathode materials for efficient energy storage and conversion. 相似文献
17.
Xiaohui He Suli Wang Yingping Yang Guangshui Tu Feng Zhang Shengmei Huang Yapeng Duan Chuanyi Zhu Changwen Cheng Defu Chen 《应用有机金属化学》2019,33(2)
Two C–C bridged Ni(II) complexes bearing β‐keto‐9‐fluorenyliminato ligands with electron‐withdrawing groups (─CF3), Ni{PhC(O)CHC[N(9‐fluorenyl)]CF2}2 (Ni 1 ) and Ni{CF3C(O)CHC[N(9‐fluorenyl)]Ph}2 (Ni 2 ), were synthesized by metal coordination reaction and different in situ bonding mechanisms. The C–C bridged bonds of Ni 1 were formed by in situ intramolecular trifluoromethyl and 9‐fluorenyl carbon–carbon cross‐coupling reaction and those of Ni 2 were formed by in situ intramolecular 9‐fluorenyl carbon–carbon radical coupling reaction mechanism. The obtained complexes were characterized using 1H NMR spectroscopy and elemental analyses. The crystal and molecular structures of Ni 1 and Ni 2 with C–C bridged configuration were determined using X‐ray diffraction. Ni 1 and Ni 2 were used as catalysts for norbornene (NB) polymerization after activation with B(C6F5)3 and the catalytic activities reached 106 gpolymer molNi?1 h?1. The copolymerization of NB and styrene catalyzed by the Ni 1 /B(C6F5)3 system showed high activity (105 gpolymer molNi?1 h?1) and the catalytic activities decreased with increasing feed content of styrene. All vinyl‐type copolymers exhibited high molecular weight (104 g mol?1), narrow molecular weight distribution (Mw/Mn = 1.71–2.80), high styrene insertion ratios (11.13–50.81%) and high thermal stability (Td > 380°C) and could be made into thin films with high transparency in the visible region (400–800 nm). 相似文献
18.
A three‐dimensional (3D) hierarchical MOF‐on‐reduced graphene oxide (MOF‐on‐rGO) compartment was successfully synthesized through an in situ reduced and combined process. The unique properties of the MOF‐on‐rGO compartment combining the polarity and porous features of MOFs with the high conductivity of rGO make it an ideal candidate as a sulfur host in lithium–sulfur (Li‐S) batteries. A high initial discharge capacity of 1250 mAh g?1 at a current density of 0.1 C (1.0 C=1675 mAh g?1) was reached using the MOF‐on‐rGO based electrode. At the rate of 1.0 C, a high specific capacity of 601 mAh g?1 was still maintained after 400 discharge–charge cycles, which could be ascribed to the synergistic effect between MOFs and rGO. Both the hierarchical structures of rGO and the polar pore environment of MOF retard the diffusion and migration of soluble polysulfide, contributing to a stable cycling performance. Moreover, the spongy‐layered rGO can buffer the volume expansion and contraction changes, thus supplying stable structures for Li‐S batteries. 相似文献
19.
Employing an Unsaturated Th4+ Site in a Porous Thorium–Organic Framework for Kr/Xe Uptake and Separation
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Dr. Yanlong Wang Wei Liu Zhuanling Bai Tao Zheng Prof. Mark A. Silver Yuxiang Li Yaxing Wang Xia Wang Prof. Juan Diwu Prof. Zhifang Chai Prof. Shuao Wang 《Angewandte Chemie (International ed. in English)》2018,57(20):5783-5787
Actinide based metal–organic frameworks (MOFs) are unique not only because compared to the transition‐metal and lanthanide systems they are substantially less explored, but also owing to the uniqueness of actinide ions in bonding and coordination. Now a 3D thorium–organic framework ( SCU‐11 ) contains a series of cages with an effective size of ca. 21×24 Å. Th4+ in SCU‐11 is 10‐coordinate with a bicapped square prism coordination geometry, which has never been documented for any metal cation complexes. The bicapped position is occupied by two coordinated water molecules that can be removed to afford a very unique open Th4+ site, confirmed by X‐ray diffraction, color change, thermogravimetry, and spectroscopy. The degassed phase ( SCU‐11‐A ) exhibits a Brunauer–Emmett–Teller surface area of 1272 m2 g?1, one of the highest values among reported actinide materials, enabling it to sufficiently retain water vapor, Kr, and Xe with uptake capacities of 234 cm3 g?1, 0.77 mmol g?1, 3.17 mmol g?1, respectively, and a Xe/Kr selectivity of 5.7. 相似文献
20.
Lingnan Chen Birong Zeng Yueguang Wu Jianjie Xie Shirong Yu Conghui Yuan Weiang Luo Yiting Xu Lizong Dai 《先进技术聚合物》2014,25(9):1069-1076
Magnetic composite nanospheres (MCS) were first prepared via mini‐emulsion polymerization. Subsequently, the hybrid core–shell nanospheres were used as carriers to support gold nanoparticles. The as‐prepared gold‐loading magnetic composite nanospheres (Au‐MCS) had a hydrophobic core embed with γ‐Fe3O4 and a hydrophilic shell loaded by gold nanoparticles. Both the content of γ‐Fe3O4 and the size of gold nanoparticles could be controlled in our experiments, which resulted in fabricating various materials. On one hand, the Au‐MCS could be used as a T2 contrast agent with a relaxivity coefficient of 362 mg?1 ml S?1 for magnetic resonance imaging. On the other hand, the Au‐MCS exhibited tunable optical‐absorption property over a wavelength range from 530 nm to 800 nm, which attributed to a secondary growth of gold nanoparticles. In addition, dynamic light scattering results of particle sizing and Zeta potential measurements revealed that Au‐MCS had a good stability in an aqueous solution, which would be helpful for further applications. Finally, it showed that the Au‐MCS were efficient catalysts for reductions of hydrophobic nitrobenzene and hydrophilic 4‐nitrophenol that could be reused by a magnetic separation process. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献