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1.
《Liver Transplantation》2018,8(1)
Nonprecious metal catalysts (NPMCs) Fe? N? C are promising alternatives to noble metal Pt as the oxygen reduction reaction (ORR) catalysts for proton‐exchange‐membrane fuel cells. Herein, a new modulation strategy is reported to the active moiety Fe? N4 via a precise “single‐atom to single‐atom” grafting of a Pt atom onto the Fe center through a bridging oxygen molecule, creating a new active moiety of Pt1? O2? Fe1? N4. The modulated Fe? N? C exhibits remarkably improved ORR stabilities in acidic media. Moreover, it shows unexpectedly high catalytic activities toward oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), with overpotentials of 310 mV for OER in alkaline solution and 60 mV for HER in acidic media at a current density of 10 mA cm?2, outperforming the benchmark RuO2 and comparable with Pt/C(20%), respectively. The enhanced multifunctional electrocatalytic properties are associated with the newly constructed active moiety Pt1? O2? Fe1? N4, which protects Fe sites from harmful species. Density functional theory calculations reveal the synergy in the new active moiety, which promotes the proton adsorption and reduction kinetics. In addition, the grafted Pt1? O2? dangling bonds may boost the OER activity. This study paves a new way to improve and extend NPMCs electrocatalytic properties through a precisely single‐atom to single‐atom grafting strategy. 相似文献
2.
Jian Yang Xiaolin Wang Yunteng Qu Xin Wang Hang Huo Qikui Fan Jin Wang Li‐Ming Yang Yuen Wu 《Liver Transplantation》2020,10(36)
Electroreduction of carbon dioxide (CO2) into high‐value and readily collectable liquid products is vital but remains a substantial challenge due to the lack of highly efficient and robust electrocatalysts. Herein, Bi‐based metal‐organic framework (CAU‐17) derived leafy bismuth nanosheets with a hybrid Bi/Bi? O interface (Bi NSs) is developed, which enables CO2 reduction to formic acid (HCOOH) with high activity, selectivity, and stability. Specially, the flow cell configuration is employed to eliminate the diffusion effect of CO2 molecules and simultaneously achieve considerable current density (200 mA cm?2) for industrial application. The faradaic efficiency for transforming CO2 to HCOOH can achieve over 85 or 90% in 1 m KHCO3 or KOH for at least 10 h despite a current density that exceeds 200 mA cm?2, outperforming most of the reported CO2 electroreduction catalysts. The hybrid Bi/Bi? O surface of leafy bismuth nanosheets boosts the adsorption of CO2 and protects the surface structure of the as‐prepared leafy bismuth nanosheets, which benefits its activity and stability for CO2 electroreduction. This work shows that modifying electrocatalysts by surface oxygen groups is a promising pathway to regulate the activity and stability for selective CO2 reduction to HCOOH. 相似文献
3.
A simple polyether‐tethered pyrrole‐polyamide dimer 1 was synthesized in 50% yield from the reaction of 2,2,2‐trichloro‐1‐(1‐methyl‐4‐nitro‐1H‐pyrrol‐2‐yl)ethanone with 2,2′‐[1,2‐ethanediylbis(oxy)]bisethanamine, and fully characterized on the basis of 1H‐ and 13C‐NMR, MS, HR‐MS, and IR data. Agarose gel‐electrophoresis study of the cleavage of plasmid pBR322 DNA by the complexes of compound 1 with seven metal ions indicated that most of the metal complexes were capable of efficiently cleaving DNA at pH 7.0 and 37°. Among them, the CuII complex exhibited the highest activity, with the maximal catalytic rate constant kmax and Michaelis constant KM being 5.61 h?1 and 7.30 mM , respectively. Spectroscopic, ESI‐MS, ethidium‐bromide (EB) displacement, and viscosity experiments indicated that compound 1 could form a 1 : 1 complex with CuII ion, and that this complex showed moderate binding affinity toward calf‐thymus DNA. 相似文献
4.
Fe?N4 Sites Embedded into Carbon Nanofiber Integrated with Electrochemically Exfoliated Graphene for Oxygen Evolution in Acidic Medium
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《Liver Transplantation》2018,8(26)
Development of inexpensive and efficient oxygen evolution reaction (OER) catalysts in acidic environment is very challenging, but it is important for practical proton exchange membrane water electrolyzers. A molecular iron–nitrogen coordinated carbon nanofiber is developed, which is supported on an electrochemically exfoliated graphene (FeN4/NF/EG) electrocatalyst through carbonizing the precursor composed of iron ions absorbed on polyaniline‐electrodeposited EG. Benefitting from the unique 3D structure, the FeN4/NF/EG hybrid exhibits a low overpotential of ≈294 mV at 10 mA cm?2 for the OER in acidic electrolyte, which is much lower than that of commercial Ir/C catalysts (320 mV) as well as all previously reported acid transitional metal‐derived OER electrocatalysts. X‐ray absorption spectroscopy coupled with a designed poisoning experiment reveals that the molecular Fe? N4 species are identified as active centers for the OER in acid. The first‐principles‐based calculations verify that the Fe? N4–doped carbon structure is capable of reducing the potential barriers and boosting the electrocatalytic OER activity in acid. 相似文献
5.
Fe2O3 Nanoparticle Seed Catalysts Enhance Cyclability on Deep (Dis)charge in Aprotic Li?O2 Batteries
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《Liver Transplantation》2018,8(18)
Although the high energy density of Li? O2 chemistry is promising for vehicle electrification, the poor stability and parasitic reactions associated with carbon‐based cathodes and the insulating nature of discharge products limit their rechargeability and energy density. In this study, a cathode material consisting of α‐Fe2O3 nanoseeds and carbon nanotubes (CNT) is presented, which achieves excellent cycling stability on deep (dis)charge with high capacity. The initial capacity of Fe2O3/CNT electrode reaches 805 mA h g?1 (0.7 mA h cm?2) at 0.2 mA cm?2, while maintaining a capacity of 1098 mA h g?1 (0.95 mA h cm?2) after 50 cycles. The operando structural, spectroscopic, and morphological analysis on the evolution of Li2O2 indicates preferential Li2O2 growth on the Fe2O3. The similar d‐spacing of the (100) Li2O2 and (104) Fe2O3 planes suggest that the latter epitaxially induces Li2O2 nucleation. This results in larger Li2O2 primary crystallites and smaller secondary particles compared to that deposited on CNT, which enhances the reversibility of the Li2O2 formation and leads to more stable interfaces within the electrode. The mechanistic insights into dual‐functional materials that act both as stable host substrates and promote redox reactions in Li? O2 batteries represent new opportunities for optimizing the discharge product morphology, leading to high cycling stability and coulombic efficiency. 相似文献
6.
Xiaojun Xu Jingli Cheng Yong Zhou Chulong Zhang Xiaoming Ou Weike Su Jinhao Zhao Guonian Zhu 《化学与生物多样性》2013,10(4):600-611
Twenty new trichodermin derivatives, 2a – 5 , containing alkoxy, acyloxy, and Br groups in 4‐, 8‐, 9‐, 10‐ and 16‐positions were synthesized and characterized. The antifungal activities of the new compounds against rice false smut (Ustilaginoidea virens), rice sheath blight (Rhizoctonia solani), and rice blast (Magnaporthe grisea) were evaluated. The results of bioassays indicated that the antifungal activities were particularly susceptible to changes at 4‐, 8‐, and 16‐positions, but low to changes at 9‐ and 10‐positions. Most of these target compounds exhibited good antifungal activities at the concentration of 50 mg l?1. Compound 4 (9‐formyltrichodermin; EC50 0.80 mg l?1) with an CHO group at 9‐position displayed nearly the same level of antifungal activity against Ustilaginoidea virens as the commercial fungicide prochloraz (EC50 0.82 mg l?1), while compound 3f ((8R)‐8‐{[(E)‐3‐phenylprop‐2‐enoyl]oxy}trichodermin; EC50 3.58 and 0.74 mg l?1) with a cinnamyloxy group at C(8) exhibited much higher antifungal activities against Rhizoctonia solani and Magnaporthe grisea than the commercial fungicides prochloraz (EC50 0.96 mg l?1) and propiconazole (EC50 5.92 mg l?1), respectively. These data reveal that compounds 3f and 4 possess high antifungal activities and may serve as lead compounds for the development of fungicides in the future. 相似文献
7.
Ji Ung Choi Jae Hyeon Jo Yun Ji Park Kug‐Seung Lee Seung‐Taek Myung 《Liver Transplantation》2020,10(27)
Herein, P′2‐type Na0.67[Ni0.1Fe0.1Mn0.8]O2 is introduced as a promising new cathode material for sodium‐ion batteries (SIBs) that exhibits remarkable structural stability during repetitive Na+ de/intercalation. The O? Ni? O? Mn? O? Fe? O bond in the octahedra of transition‐metal layers is used to suppress the elongation of the Mn? O bond and to improve the electrochemical activity, leading to the highly reversible Na storage mechanism. A high discharge capacity of ≈220 mAh g?1 (≈605 Wh kg?1) is delivered at 0.05 C (13 mAg?1) with a high reversible capacity of ≈140 mAh g?1 at 3 C and excellent capacity retention of 80% over 200 cycles. This performance is associated with the reversible P′2–OP4 phase transition and small volume change upon charge and discharge (≈3%). The nature of the sodium storage mechanism in a full cell paired with a hard carbon anode reveals an unexpectedly high energy density of ≈542 Wh kg?1 at 0.2 C and good capacity retention of ≈81% for 500 cycles at 1 C (260 mAg?1). 相似文献
8.
Ming Zhang Haiqun Li Minggang Deng Xiaocheng Weng Heng Ma Shuo Feng Yangyang Zhou Xiang Zhou 《化学与生物多样性》2012,9(1):170-180
In the presence of hemin and under appropriate conditions, some modalities of G‐quadruplexes can form a peroxidase‐like DNAzyme that has been widely used in biology. Structure? function studies on the DNAzyme revealed that its catalytic ability may be dependent on the unimolecular parallel G‐quadruplex. In this report, we present the preliminary investigation on the relationship between the structure and function of DNAzymes through a terminal oligo modification in G‐quadruplex sequences by adding different lengths of oligo‐dT to the 3′‐ or 5′‐end of the aptamers. The results suggested that adding dTn to the 5′‐end of the DNA sequence of the enzyme improved the ability of hemin to bind with DNA, but the addition of dTn to the 3′‐end decreased the binding ability of hemin for DNA. The increased stability of the assembled DNAzyme would lead to more favorable binding between the enzyme and substrate (H2O2), facilitating higher peroxidase activity; on the contrary, with lower stability of the DNAzyme complex, we observed reduced peroxidase activity. 相似文献
9.
Synthesis and Antifungal Activity of 2‐Hydroxy‐4,5‐methylenedioxyaryl Ketones as Analogues of Kakuol
In a study aiming to determine the structural elements essential to the antifungal activity of kakuol, we synthesized a series of 2‐hydroxy‐4,5‐methylenedioxyaryl ketones, and we assayed their in vitro antifungal activity. The most sensitive target organisms to the action of these class of compounds were Phytophthora infestans, Phytium ultimum, Cercospora beticola, Cladosporium cucumerinum, and Rhizoctonia solani. Most of the analogs showed a remarkable in vitro activity, and some of them appeared significantly more effective than the natural product. The biological activity was mainly affected by introducing structural modification on the carbonyl moiety of the natural‐product molecule. In particular, compound 5a , bearing a C?C bond conjugated to the C?O group, was found active with a MIC value of 10 μg ml?1 against Cladosporium cucumerinum. The results suggest that 2‐hydroxy‐4,5‐methylenedioxyaryl ketones can be considered promising candidates in the development of new antifungal compounds. 相似文献
10.
Joanna Matysiak Monika M. Karpińska Andrzej Niewiadomy Joanna Wietrzyk Dagmara Kłopotowska 《化学与生物多样性》2012,9(1):48-57
A one‐pot synthesis of new 4‐(1,3‐thiazolo[5,4‐b]pyridin‐2‐yl)benzene‐1,3‐diols has been described. The compounds were prepared by the reaction of sulfinylbis[(2,4‐dihydroxyphenyl)methanethione] derivatives, with various substituents in the aryl rings, with 2‐chloropyridin‐3‐amines. Their structures were deduced from IR and, 1H‐ and 13C‐NMR spectroscopic, mass spectrometric, and elemental analyses. The antiproliferative properties of some of the products against human cancer cell lines were comparable to those of cisplatin. Structure? activity analysis showed that the presence of hydrophobic substituents in both heterocyclic fused and phenyl rings of the compounds improves their biological effects. Further, an additional OH group in the resorcinol moiety reduced the antiproliferative activity. 相似文献
11.
Phase Transformation Induced Capacitance Activation for 3D Graphene‐CoO Nanorod Pseudocapacitor
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Yun Guang Zhu Ye Wang Yumeng Shi Zhi Xiang Huang Lin Fu Hui Ying Yang 《Liver Transplantation》2014,4(9)
Development of a pseudocapacitor over the integration of metal oxide on carbonaceous materials is a promising step towards energy storage devices with high energy and power densities. Here, a self‐assembled cobalt oxide (CoO) nanorod cluster on three‐dimensional graphene (CoO‐3DG) is synthesized through a facile hydrothermal method followed by heat treatment. As an additive‐free electrode, CoO‐3DG exhibits good electrochemical performance. Compared with CoO nanorod clusters grown on Ni foam (i.e., CoO‐Ni, ≈680 F g?1 at 1 A g?1 and ≈400 F g?1 at 20 A g?1), CoO‐3DG achieves much higher capacitance (i.e., ≈980 F g?1 at 1 A g?1 and ≈600 F g?1 at 20 A g?1) with excellent cycling stability of 103% retention of specific capacitance after 10 000 cycles. Furthermore, it shows an interesting activation process and instability with a redox reaction for CoO. In addition, the phase transformation from CoO nanorods to Co3O4 nanostructures was observed and investigated after charge and discharge process, which suggests the activation kinetics and the phase transformable nature of CoO based nanostructure. These observations demonstrate phase transformation with morphological change induced capacitance increasement in the emergent class of metal oxide materials for electrochemical energy storage device. 相似文献
12.
《Liver Transplantation》2018,8(20)
Organic–inorganic halide perovskites are efficient absorbers for solar cells. Nevertheless, the trap states at the surfaces and grain boundaries are a detrimental factor compromising the device performance. Here, an organic dye (AQ310) is employed as passivator to reduce the trap states of the perovskites and promote better stability. The results demonstrate that the trap states of perovskite are minimized by the presence of AQ310's ? COOH group and the formation of coordination with under‐coordinated Pb2+ ions. The resulting carrier recombination time is prolonged and verified by the photoluminescence and open‐circuit voltage decay measurements. Consequently, the best average power conversion efficiency (PCE) of 19.43% is achieved for the perovskite solar cell (PSC) with AQ310 passivation, as compared with a low average PCE of 17.98% for the PSC without AQ310 passivation. 相似文献
13.
Federica Vacondio Claudia Silva Lisa Flammini Vigilio Ballabeni Elisabetta Barocelli Marco Mor 《化学与生物多样性》2012,9(7):1231-1239
In the present article, we report on the kinetics of brain penetration in rats of the H3R antagonist 1,1′‐[1,1′‐biphenyl‐4,4′‐diylbis(methylene)]bis‐[piperidine] ( 1 ), which had shown a favorable in vitro pharmacological profile and in vivo potency in preventing scopolamine‐induced amnesia. Two different approaches were employed: high‐performance liquid chromatography/electrospray‐mass spectrometry (HPLC/ESI‐MS) and ex vivo binding against the labeled agonist [3H]‐(R)‐α‐methylhistamine ([3H]RAMHA). Starting from the structure of 1 , the rigid piperidine ring was replaced by a flexible dipropylamino group (see 2 ) or by a morpholino ring (see 3 ), endowed with lower basicity. The effect of replacement on rat plasma and brain disposition in the 24 h after administration was analyzed. High (μM ) and persistent concentrations of 1 were found in rat plasma, while plasma levels were significantly lower (range: 0–200 nM ) for the other two derivatives. This could be explained, among other factors, by the higher stability, observed for 1 , to liver metabolic cleavage. The applied chemical modulation had an important effect on in vivo brain disposition, as, despite the comparable physico‐chemical properties, 2 did not show the tendency to accumulate within the brain, as stated by its brain vs. plasma concentration ratios, if compared to 1 . These structure? property relationships should be taken into account in the pharmacokinetic optimization of new series of H3 receptor antagonists. 相似文献
14.
Yolk–Shell NiS2 Nanoparticle‐Embedded Carbon Fibers for Flexible Fiber‐Shaped Sodium Battery
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Fiber‐shaped rechargeable batteries hold promise as the next‐generation energy storage devices for wearable electronics. However, their application is severely hindered by the difficulty in fabrication of robust fiber‐like electrodes with promising electrochemical performance. Herein, yolk–shell NiS2 nanoparticles embedded in porous carbon fibers (NiS2?PCF) are successfully fabricated and developed as high‐performance fiber electrodes for sodium storage. Benefiting from the robust embedded structure, 3D porous and conductive carbon network, and yolk–shell NiS2 nanoparticles, the as‐prepared NiS2?PCF fiber electrode achieves a high reversible capacity of about 679 mA h g?1 at 0.1 C, outstanding rate capability (245 mA h g?1 at 10 C), and ultrastable cycle performance with 76% capacity retention over 5000 cycles at 5 C. Notably, a flexible fiber‐shaped sodium battery is assembled, and high reversible capacity is kept at different bending states. This work offers a new electrode‐design paradigm toward novel carbon fiber electrodes embedded with transition metal oxides/sulfides/phosphides for application in flexible energy storage devices. 相似文献
15.
Xiao‐Jin Zhang Xiang Li Ying‐Rui Yang Hao‐Peng Sun Yuan Gao Lei Zhang Jin‐Xin Wang Qing‐Long Guo Qi‐Dong You 《化学与生物多样性》2012,9(10):2295-2308
Gambogic acid (GA), a natural product, was identified as a promising antitumor agent. To further explore the structure? activity relationship of GA and discover novel GA derivatives as antitumor agents, 19 novel GA derivatives modified at C(34) were synthesized and evaluated against A549, BGC‐823, U251, HepG2, and MB‐231 cancer cell lines by cellular assays. Among them, 15 compounds were found to be more potent than GA against some cancer cell lines. Notably, compound 3 possessed potent inhibitory activities against five cell lines with IC50 values ranging between 0.24 and 1.09 μM . Compounds 9 and 18 were seven to eightfold more active than GA against A549 cell line. Chemical modification at C(34) of GA by introducing of hydrophilic aliphatic amines resulted in increased activity and improved drug‐like properties. These findings will enhance our understanding of the SAR of GA and can lead to the discovery of novel GA derivatives as potential antitumor agents. 相似文献
16.
The interaction of bioactive protoberberine alkaloids berberine, palmatine, and coralyne with the DNA triplex poly(dT)⋅(poly(dA)⋅poly(dT)) was studied using biophysical and calorimetric techniques. All three alkaloids bound the triplex cooperatively. Berberine and palmatine predominantly stabilized the triplex structure, while coralyne stabilized both triplex and duplex structures as inferred from optical thermal melting profiles. Fluorescence quenching, polarization, and viscometric studies hinted at an intercalative mode of binding for the alkaloids to the triplex, coralyne being more strongly intercalated compared to partial intercalation of berberine and palmatine. The overall affinity of coralyne was two order higher (2.29×107 M −1) than that of berberine (3.43×105 M −1) and palmatine (2.34×105 M −1). Isothermal titration calorimetric studies revealed that the binding to the triplex was favored by negative enthalpy change (ΔH=−3.34 kcal/mol) with favorable entropy contribution (TΔS = 4.07 kcal/mol) for berberine, favored by almost equal negative enthalpy (ΔH =−3.88 kcal/mol) and entropy changes (TΔS = 3.37 kcal/mol) for palmatine, but driven by large enthalpy contributions (ΔH =−25.62 kcal/mol and TΔS =−15.21 kcal/mol) for coralyne. These results provide new insights on the binding of isoquinoline alkaloids to the DNA triplex structure. 相似文献
17.
Fengping Xiao Xuming Yang Hongkang Wang Jun Xu Yulong Liu Denis Y. W. Yu Andrey L. Rogach 《Liver Transplantation》2020,10(23)
Practical applications of room temperature sodium–sulfur batteries are still inhibited by the poor conductivity and slow reaction kinetics of sulfur, and dissolution of intermediate polysulfides in the commonly used electrolytes. To address these issues, starting from a novel 3D Zn‐based metal–organic framework with 2,5‐thiophenedicarboxylic acid and 1,4‐bis(pyrid‐4‐yl) benzene as ligands, a S, N‐doped porous carbon host with 3D tubular holes for sulfur storage is fabricated. In contrast to the commonly used melt‐diffusion method to confine sulfur physically, a vapor‐infiltration method is utilized to achieve sulfur/carbon composite with covalent bonds, which can join electrochemical reaction without low voltage activation. A polydopamine derived N‐doped carbon layer is further coated on the composite to confine the high‐temperature‐induced gas‐phase sulfur inside the host. S and N dopants increase the polarity of the carbon host to restrict diffusion of sulfur, and its 3D porous structure provides a large storage area for sulfur. As a result, the obtained composite shows outstanding electrochemical performance with 467 mAh g?1 (1262 mAh g?1(sulfur)) at 0.1 A g?1, 270 mAh g?1 (730 mAh g?1(sulfur)) after 1000 cycles at 1 A g?1 and 201 mAh g?1 (543 mAh g?1(sulfur)) at 5.0 A g?1. 相似文献
18.
Prostate cancer is one of the most common cancer forms among males of Western countries. Natural products proved to be an unparalleled source of molecular diversity. The 4‐(hydroxyphenylmethylidene)hydantoin (PMH; 1 ), (5Z)‐5‐(4‐hydroxybenzylidene)imidazolidine‐2,4‐dione, was isolated from the Red Sea sponge Hemimycale arabica, and recently showed junctional complexes stabilization, anti‐invasive, and antimetastatic activities in vitro and in vivo. The related synthetic analogue, (5Z)‐5‐[4‐(ethylsulfanyl)benzylidene]imidazolidine‐2,4‐dione ( 2 ), showed several‐fold‐improved in vivo antimetastatic properties against the highly invasive prostate cancer. To further optimize the activity of PMHs, various ligand‐based strategies were used including the extension of the structure, structural simplification, linker extension, and computer‐assisted CoMFA (Comparative Molecular Field Analysis) results. These strategies yielded thirty 2nd‐generation PMHs, designed based on the 1st‐generation PMHs, such as 1 and 2 . Wound‐healing assay was selected to evaluate the in vitro anti‐migratory potential of these new PMHs against the PC‐3 cell line. Several active PMHs, including 10, 13, 24, 29 , with nearly twelvefold enhancement of activity vs. 2 , were identified. Active compounds were then used to build a pharmacophore model using the SYBYL's DIStance COmparison technique (DISCOtech). Active PMHs were also screened for fragment‐based drug likeness using the OSIRIS program, and an overall drug score was also calculated. Interestingly, the overall drug scores of 24 and 29 along with their anti‐migratory activity were significantly greater than those of 1 and 2 . In conclusion, PMHs can be the appropriate scaffolds for the urgently needed drug candidates for the control of androgen independent prostate cancer. 相似文献
19.
Popcorn Inspired Porous Macrocellular Carbon: Rapid Puffing Fabrication from Rice and Its Applications in Lithium–Sulfur Batteries
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Yu Zhong Xinhui Xia Shengjue Deng Jiye Zhan Ruyi Fang Yang Xia Xiuli Wang Qiang Zhang Jiangping Tu 《Liver Transplantation》2018,8(1)
The advancement of electrochemical energy storage is closely bound up with the breakthrough of controllable fabrication of energy materials. Inspired by a popcorn fabrication from corn raw, herein a unique porous macrocellular carbon composed of cross‐linked nano/microsheets by a powerful puffing of rice precursor is described. The rice is directly puffed with a volume enlargement of ≈20 times when it is instantaneously released from a sealed environment with a high pressure of 1.0 MPa at 200 °C. Interestingly, when metal (e.g., Ni) nanoparticles are embedded in the puffed rice derived carbon (PRC), high‐quality PRC/metal composites are achieved with attractive properties of a high electrical conductivity of ≈7.2 × 104 S m?1, a large porosity of 85.1%, and a surface area of 1492.2 m2 g?1. The PRC/Ni are employed as a host in lithium–sulfur batteries. The designed PRC/Ni/S electrode exhibits a high reversible capacity of 1257.2 mA h g?1 at 0.2 C, a prolonged cycle life (821 mA h g?1 after 500 cycles), and enhanced rate capability, much better than other counterparts (PRC/S and rGO/S). The excellent properties are attributed to the advantages of PRC/Ni network with a high electrical conductivity, strong adsorption/blocking ability for polysulfides, and interconnected porous framework. 相似文献
20.
Ice Templated Free‐Standing Hierarchically WS2/CNT‐rGO Aerogel for High‐Performance Rechargeable Lithium and Sodium Ion Batteries
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Ye Wang Dezhi Kong Wenhui Shi Bo Liu Glenn Joey Sim Qi Ge Hui Ying Yang 《Liver Transplantation》2016,6(21)
A hybrid nanoarchitecture aerogel composed of WS2 nanosheets and carbon nanotube‐reduced graphene oxide (CNT‐rGO) with ordered microchannel three‐dimensional (3D) scaffold structure was synthesized by a simple solvothermal method followed by freeze‐drying and post annealing process. The 3D ordered microchannel structures not only provide good electronic transportation routes, but also provide excellent ionic conductive channels, leading to an enhanced electrochemical performance as anode materials both for lithium‐ion batteries (LIBs) and sodium‐ion batteries (SIBs). Significantly, WS2/CNT‐rGO aerogel nanostructure can deliver a specific capacity of 749 mA h g?1 at 100 mA g?1 and a high first‐cycle coulombic efficiency of 53.4% as the anode material of LIBs. In addition, it also can deliver a capacity of 311.4 mA h g?1 at 100 mA g?1, and retain a capacity of 252.9 mA h g?1 at 200 mA g?1 after 100 cycles as the anode electrode of SIBs. The excellent electrochemical performance is attributed to the synergistic effect between the WS2 nanosheets and CNT‐rGO scaffold network and rational design of 3D ordered structure. These results demonstrate the potential applications of ordered CNT‐rGO aerogel platform to support transition‐metal‐dichalcogenides (i.e., WS2) for energy storage devices and open up a route for material design for future generation energy storage devices. 相似文献