scispace - formally typeset
Search or ask a question

Showing papers by "Nankai University published in 2013"


Journal ArticleDOI
19 Apr 2013-Science
TL;DR: Plasmonic couplers that overcome limits in the polarization sensitivity of the coupling efficiency and in controlling the directionality of the SPPs are designed and demonstrated using polarization-sensitive apertures in a gold film.
Abstract: Light can be coupled into propagating electromagnetic surface waves at a metal-dielectric interface known as surface plasmon polaritons (SPPs). This process has traditionally faced challenges in the polarization sensitivity of the coupling efficiency and in controlling the directionality of the SPPs. We designed and demonstrated plasmonic couplers that overcome these limits using polarization-sensitive apertures in a gold film. Our devices enable polarization-controlled tunable directional coupling with polarization-invariant total conversion efficiency and preserve the incident polarization information. Both bidirectional and unidirectional launching of SPPs are demonstrated. The design is further applied to circular structures that create radially convergent and divergent SPPs, illustrating that this concept can be extended to a broad range of applications.

1,077 citations


Journal ArticleDOI
TL;DR: The cell performance of the arieslamine organic dyes are compared, providing a comprehensive overview of arylamineorganic dyes, demonstrating the advantages/disadvantages of each class, and pointing out the field that needs to reinforce the research direction in the further application of DSCs.
Abstract: Arylamine organic dyes with donor (D), π-bridge (π) and acceptor (A) moieties for dye-sensitized solar cells (DSCs) have received great attention in the last decade because of their high molar absorption coefficient, low cost and structural variety. In the early stages, the efficiency of DSCs with arylamine organic dyes with D–π–A character was far behind that of DSCs with ruthenium(II) complexes partly due to the lack of information about the relationship between the chemical structures and the photovoltaic performance. However, exciting progress has been recently made, and power conversion efficiencies over 10% were obtained for DSCs with arylamine organic dyes. It is thus that the recent research and development in the field of arylamine organic dyes employing an iodide/triiodide redox couple or polypyridyl cobalt redox shuttles as the electrolytes for either DSCs or solid-state DSCs has been summarized. The cell performance of the arylamine organic dyes are compared, providing a comprehensive overview of arylamine organic dyes, demonstrating the advantages/disadvantages of each class, and pointing out the field that needs to reinforce the research direction in the further application of DSCs.

970 citations


Journal ArticleDOI
Fan Zhang1, Tengfei Zhang1, Xi Yang1, Long Zhang1, Kai Leng1, Yi Huang1, Yongsheng Chen1 
TL;DR: In this paper, a supercapacitor-battery hybrid energy storage device was designed and fabricated, which combines an electrochemical double layer capacitance (EDLC) type positive electrode with a Li-ion battery type negative electrode.
Abstract: In pursuing higher energy density with no sacrifice of power density, a supercapacitor-battery hybrid energy storage device—combining an electrochemical double layer capacitance (EDLC) type positive electrode with a Li-ion battery type negative electrode—has been designed and fabricated. Graphene is introduced to both electrodes: an Fe3O4/graphene (Fe3O4/G) nanocomposite with high specific capacity as negative electrode material, and a graphene-based three-dimensional porous carbon material (3DGraphene) with high surface area (∼3355 m2 g−1) as positive electrode material. The Fe3O4/G nanocomposite shows a high reversible specific capacity exceeding 1000 mA h g−1 at 90 mA g−1 and remaining at 704 mA h g−1 at 2700 mA g−1, as well as excellent rate capability and improved cycle stability. Meanwhile the 3DGraphene positive electrode also displays great electrochemical performance. With these two graphene-enhanced electrode materials and using the best recommended industry evaluation method, the hybrid supercapacitor Fe3O4/G//3DGraphene demonstrates an ultrahigh energy density of 147 W h kg−1 (power density of 150 W kg−1), which also remains of 86 W h kg−1 even at high power density of 2587 W kg−1, so far the highest value of the reported hybrid supercapacitors. Furthermore, the energy density of the hybrid supercapacitor is comparable to lithium ion batteries, and the power density also reaches that of symmetric supercapacitors, indicating that the hybrid supercapacitor could be a very promising novel energy storage system for fast and efficient energy storage in the future.

839 citations


Journal ArticleDOI
TL;DR: The better PCEs were achieved by improving the short-circuit current density without sacrificing the high open-circuits voltage and fill factor through the strategy of incorporating the advantages of both conventional small molecules and polymers for OPVs.
Abstract: Three small molecules named DR3TBDTT, DR3TBDTT-HD, and DR3TBD2T with a benzo[1,2-b:4,5-b']dithiophene (BDT) unit as the central building block have been designed and synthesized for solution-processed bulk-heterojunction solar cells. Power conversion efficiencies (PCEs) of 8.12% (certified 7.61%) and 8.02% under AM 1.5G irradiation (100 mW cm(-2)) have been achieved for DR3TBDTT- and DR3TBDT2T-based organic photovoltaic devices (OPVs) with PC71BM as the acceptor, respectively. The better PCEs were achieved by improving the short-circuit current density without sacrificing the high open-circuit voltage and fill factor through the strategy of incorporating the advantages of both conventional small molecules and polymers for OPVs.

680 citations


Journal ArticleDOI
TL;DR: In this paper, the authors summarize the recent progress in high-voltage cathode materials and matched electrolytes, as well as the optimization of other cell components such as conductive agents, binders, positive cans, separators and current collectors.

677 citations


Journal ArticleDOI
M. Ablikim, M. N. Achasov1, Xiaocong Ai, O. Albayrak2  +365 moreInstitutions (50)
TL;DR: In this article, the process e(+)e(-) -> pi(+)pi(-) J/psi at a center-of-mass energy of 4.260 GeV using a 525 pb(-1) data sample collected with the BESIII detector operating at the Beijing Electron Positron Collider was studied.
Abstract: We study the process e(+)e(-) -> pi(+)pi(-) J/psi at a center-of-mass energy of 4.260 GeV using a 525 pb(-1) data sample collected with the BESIII detector operating at the Beijing Electron Positron Collider. The Born cross section is measured to be (62.9 +/- 1.9 +/- 3.7) pb, consistent with the production of the Y(4260). We observe a structure at around 3.9 GeV/c(2) in the pi(+/-) J/psi mass spectrum, which we refer to as the Z(c)(3900). If interpreted as a new particle, it is unusual in that it carries an electric charge and couples to charmonium. A fit to the pi(+/-) J/psi invariant mass spectrum, neglecting interference, results in a mass of (3899.0 +/- 3.6 +/- 4.9) MeV/c(2) and a width of (46 +/- 10 +/- 20) MeV. Its production ratio is measured to be R = (sigma(e(+)e(-) -> pi(+/-) Z(c)(3900)(-/+) -> pi(+)pi(-) J/psi)/sigma(e(+)e(-) -> pi(+)pi(-) J/psi)) = (21.5 +/- 3.3 +/- 7.5)%. In all measurements the first errors are statistical and the second are systematic.

677 citations


Journal ArticleDOI
Qing Tang1, Zhen Zhou1
TL;DR: In this paper, the authors summarize the recent progress on graphene-analogous low-dimensional materials (2D nanosheets and 1D nanoribbons) from both experimental and computational side, and emphasis is placed on structure, properties, preparation, and potential applications of graphene analogous materials as well as the comparison with graphene.

669 citations


Journal ArticleDOI
TL;DR: In this paper, the authors presented a simple and green but very efficient approach using two standard and simple industry steps to make such three-dimensional graphene-based porous materials at the bulk scale, with ultrahigh specific surface area (SSA) and electrical conductivity at bulk state.
Abstract: Until now, few sp2 carbon materials simultaneously exhibit superior performance for specific surface area (SSA) and electrical conductivity at bulk state. Thus, it is extremely important to make such materials at bulk scale with those two outstanding properties combined together. Here, we present a simple and green but very efficient approach using two standard and simple industry steps to make such three-dimensional graphene-based porous materials at the bulk scale, with ultrahigh SSA (3523 m2/g) and excellent bulk conductivity. We conclude that these materials consist of mainly defected/wrinkled single layer graphene sheets in the dimensional size of a few nanometers, with at least some covalent bond between each other. The outstanding properties of these materials are demonstrated by their superior supercapacitor performance in ionic liquid with specific capacitance and energy density of 231 F/g and 98 Wh/kg, respectively, so far the best reported capacitance performance for all bulk carbon materials.

629 citations


Journal ArticleDOI
Fangyi Cheng1, Tianran Zhang1, Yi Zhang1, Jing Du1, Xiaopeng Han1, Jun Chen1 
TL;DR: Both experimental and computational studies indicate that the catalytic activity of MnO(2) towards oxygen reduction is enhanced by introducing a modest concentration of oxygen vacancies.
Abstract: Oxygen-vacant nanocrystalline MnO(2) has been prepared by the simple process of annealing pristine oxide in Ar or O(2) . Both experimental and computational studies indicate that the catalytic activity of MnO(2) towards oxygen reduction is enhanced by introducing a modest concentration of oxygen vacancies.

625 citations


Journal ArticleDOI
TL;DR: Small molecules based OPV (SM-OPV) offers further advantages, including a defined structure for more reproducible performance, higher mobility and open circuit voltage, and easier synthetic control that leads to more diversified structures.
Abstract: Energy remains a critical issue for the survival and prosperity of humancivilization. Many experts believe that the eventual solution for sustainable energy is the use of direct solar energy as the main energy source. Among the options for renewable energy, photovoltaic technologies that harness solar energy offer a way to harness an unlimited resource and minimum environment impact in contrast with other alternatives such as water, nuclear, and wind energy.Currently, almost all commercial photovoltaic technologies use Si-based technology, which has a number of disadvantages including high cost, lack of flexibility, and the serious environmental impact of the Si industry. Other technologies, such as organic photovoltaic (OPV) cells, can overcome some of these issues. Today, polymer-based OPV (P-OPV) devices have achieved power conversion efficiencies (PCEs) that exceed 9%. Compared with P-OPV, small molecules based OPV (SM-OPV) offers further advantages, including a defined structure for more reproducible...

612 citations


Journal ArticleDOI
TL;DR: The most recent progress on graphene-related nanomaterials, including doped graphene and derived graphene nanoribbons, graphene oxide, graphane, fluorographene, graphyne, graphdiyne, and porous graphene are discussed, and tuning their stability, electronic and magnetic properties by chemical functionalization is emphasized.
Abstract: In this review, we discuss the most recent progress on graphene-related nanomaterials, including doped graphene and derived graphene nanoribbons, graphene oxide, graphane, fluorographene, graphyne, graphdiyne, and porous graphene, from both experimental and theoretical perspectives, and emphasize tuning their stability, electronic and magnetic properties by chemical functionalization.

Journal ArticleDOI
Peng Wu1, Xiu-Ping Yan1
TL;DR: The lifetime of dopant emission from transition-metal ion or lanthanide ion-doped QDs is generally longer than that of the bandgap or defect-related emission of host, and that of biological Background fluorescence, providing great opportunities to eliminate background fluorescence for biosensing and bioimaging.
Abstract: Quantum dots (QDs) have received great interest for diverse applications due to their distinct advantages, such as narrow and symmetric emission with tunable colors, broad and strong absorption, reasonable stability, and solution processibility Doped QDs not only potentially retain almost all of the above advantages, but also avoid the self-quenching problem due to their substantial ensemble Stokes shift Two obvious advantages of doped QDs, especially doped ZnS QDs, over typical CdSe@ZnS and CdTe QDs are longer dopant emission lifetime and potentially lower cytotoxicity The lifetime of dopant emission from transition-metal ion or lanthanide ion-doped QDs is generally longer than that of the bandgap or defect-related emission of host, and that of biological background fluorescence, providing great opportunities to eliminate background fluorescence for biosensing and bioimaging For bioimaging applications, fluorescent dopants may mitigate toxicity problems by producing visible or infrared emission in nanocrystals made from less-harmful elements than those currently used In this review, recent advances in utilizing doped QDs for chemo/biosensing and bioimaging are discussed, and the synthetic routes and optical properties of doped QDs that make them excellent probes for various strategies in chemo/biosensing and bioimaging are highlighted Moreover, perspectives on future exploration of doped QDs for chemo/biosensing and bioimaging are also given

Journal ArticleDOI
TL;DR: In this article, the authors investigated the adsorption and diffusion of lithium on the recently synthesized VS2 monolayer, in comparison with MoS2 and graphite.
Abstract: By means of density functional theory computations, we systematically investigated the adsorption and diffusion of lithium on the recently synthesized VS2 monolayer, in comparison with MoS2 monolayer and graphite. Intrinsically metallic, VS2 monolayer has a higher theoretical capacity (466 mAh/g), a lower or similar Li diffusion barrier as compared to MoS2 and graphite, and has a low average open-circuit voltage of 0.93 V (vs Li/Li+). Our results suggest that VS2 monolayer can be utilized as a promising anode material for Li ion batteries with high power density and fast charge/discharge rates.

Journal ArticleDOI
TL;DR: The synthesis of NIR-emitting long-persistent luminescent nanoparticles (LPLNPs) Zn2.94Ga1.96Ge2O10:Cr(3+),Pr(3+) by a citrate sol-gel method in combination with a subsequent reducing atmosphere-free calcination and PEGylation greatly improves the biocompatibility and water solubility of the LPLNPS.
Abstract: Near infrared (NIR)-emitting persistent luminescent nanoparticles (PLNPs) have great potential for in vivo bioimaging with the advantages of no need for in situ excitation, high signal-to-noise ratio, and deep tissue penetration. However, functional NIR-emitting PLNPs with long afterglow for long-term in vivo imaging are lacking. Here, we show the synthesis of NIR-emitting long-persistent luminescent nanoparticles (LPLNPs) Zn2.94Ga1.96Ge2O10:Cr(3+),Pr(3+) by a citrate sol-gel method in combination with a subsequent reducing atmosphere-free calcination. The persistent luminescence of the LPLNPs is significantly improved via codoping Pr(3+)/Cr(3+) and creating suitable Zn deficiency in zinc gallogermanate. The LPLNP powder exhibits bright NIR luminescence in the biological transparency window with a superlong afterglow time of over 15 days. A persistent energy transfer between host and Cr(3+) ion in the LPLNPs is observed and its mechanism is discussed. PEGylation greatly improves the biocompatibility and water solubility of the LPLNPs. Further bioconjugation with c(RGDyK) peptide makes the LPLNPs promising for long-term in vivo targeted tumor imaging with low toxicity.

Journal ArticleDOI
TL;DR: A direct correlation between the surface specific photocatalytic activity and the surface/bulk defect density ratio could be drawn for both anataseTiO2 and rutile TiO2.
Abstract: The sole effect of surface/bulk defects of TiO2 samples on their photocatalytic activity was investigated. Nano-sized anatase and rutile TiO2 were prepared by hydrothermal method and their surface/bulk defects were adjusted simply by calcination at different temperatures, i.e. 400–700 °C. High temperature calcinations induced the growth of crystalline sizes and a decrease in the surface areas, while the crystalline phase and the exposed facets were kept unchanged during calcination, as indicated by the characterization results from XRD, Raman, nitrogen adsorption–desorption, TEM and UV-Vis spectra. The existence of surface/bulk defects in calcined TiO2 samples was confirmed by photoluminescence and XPS spectra, and the surface/bulk defect ratio was quantitatively analyzed according to positron annihilation results. The photocatalytic activity of calcined TiO2 samples was evaluated in the photocatalytic reforming of methanol and the photocatalytic oxidation of α-phenethyl alcohol. Based on the characterization and catalytic results, a direct correlation between the surface specific photocatalytic activity and the surface/bulk defect density ratio could be drawn for both anatase TiO2 and rutile TiO2. The surface defects of TiO2, i.e. oxygen vacancy clusters, could promote the separation of electron–hole pairs under irradiation, and therefore, enhance the activity during photocatalytic reaction.

Journal ArticleDOI
TL;DR: This review presents the fundamentals and recent advances related to the field of ordered mesoporous carbon materials from the direct synthesis strategy of block copolymer soft-templating, with a focus on their controllable preparation, modification and potential applications.
Abstract: Ordered mesoporous carbon materials have recently aroused great research interest because of their widespread applications in many areas such as adsorbents, catalysts and supports, gas storage hosts, and electrode materials. The direct synthesis strategy from organic–organic self-assembly involving the combination of polymerizable precursors and block copolymer templates is expected to be more flexible in preparing mesoporous carbons, compared with the traditional nanocasting strategy of complicated and high-cost procedures using mesoporous silica materials as the hard template. In this review, we present the fundamentals and recent advances related to the field of ordered mesoporous carbon materials from the direct synthesis strategy of block copolymer soft-templating, with a focus on their controllable preparation, modification and potential applications. Under the guidance of their formation mechanism, the preparation of ordered mesoporous carbons are discussed in detail by consulting different experimental conditions, including synthetic pathways, precursors, catalysts and templates. Both the mesopore size and morphology control are introduced. The potential applications of pure mesoporous carbons, nonmetallic- and metallic-modified mesoporous carbons, and some interpenetrating carbon-based composites are demonstrated. Furthermore, remarks on the challenges and perspectives of research directions are proposed for further development of the ordered mesoporous carbons (232 references).

Journal ArticleDOI
TL;DR: Application of biochar in soil has been shown to result in decreased efficacy of pesticides, which indicates a trade-off between the potentially promising effect of bio char on pesticide remediation and its negative effect on pesticide efficacy.

Journal ArticleDOI
17 Jan 2013-Cell
TL;DR: The crystal structure of MDA5 bound to dsRNA is reported, which shows how, using the same domain architecture, MDA5 recognizes the internal duplex structure, whereas RIG-I recognizes the terminus of ds RNA.

Journal ArticleDOI
TL;DR: The possible mechanism for the quenching effect of Fe(3+) on the fluorescence of MIL-53(Al) was elucidated by inductively coupled plasma-mass spectrometry, X-ray diffraction spectromaetry, and Fourier transform infrared spectrometer.
Abstract: Fluorescent metal–organic frameworks (MOFs) have received great attention in sensing application. Here, we report the exploration of fluorescent MIL-53(Al) for highly selective and sensitive detection of Fe3+ in aqueous solution. The cation exchange between Fe3+ and the framework metal ion Al3+ in MIL-53(Al) led to the quenching of the fluorescence of MIL-53(Al) due to the transformation of strong-fluorescent MIL-53(Al) to weak-fluorescent MIL-53(Fe), allowing highly selective and sensitive detection of Fe3+ in aqueous solution with a linear range of 3–200 μM and a detection limit of 0.9 μM. No interferences from 0.8 M Na+; 0.35 M K+; 11 mM Cu2+; 10 mM Ni2+; 6 mM Ca2+, Pb2+, and Al3+; 5.5 mM Mn2+; 5 mM Co2+ and Cr3+; 4 mM Hg2+, Cd2+, Zn2+, and Mg2+; 3 mM Fe2+; 0.8 M Cl–; 60 mM NO2– and NO3–; 10 mM HPO42–, H2PO4–, SO32–, SO42–, and HCOO–; 8 mM CO32–, HCO3–, and C2O42–; and 5 mM CH3COO– were found for the detection of 150 μM Fe3+. The possible mechanism for the quenching effect of Fe3+ on the fluorescence o...

Journal ArticleDOI
Chao Zhang1, Yonghai Jiang, Yunlin Li1, Zhongxin Hu1, Lei Zhou1, Minghua Zhou1 
TL;DR: In this paper, a comprehensive review on the development and application of 3D electrochemical process is presented, including anode and cathode materials, particle electrode materials and their catalysts.

Journal ArticleDOI
TL;DR: Imaging of HeLa cells and HepG2 cells, a human cervical cancer cell line, was observed with high resolution using N-Cdots as a probe and validates their use in imaging applications and their multicolor property in the living cell system.
Abstract: Carbon dots (Cdots) are an important probe for imaging and sensing applications because of their fluorescence property, good biocompatibility, and low toxicity. However, complex procedures and strong acid treatment are often required and Cdots suffer from low photoluminescence (PL) emission. Herein, a facile and general strategy using carbonization of precursors and then extraction with solvents is proposed for the preparation of nitrogen-doped Cdots (N-Cdots) with 3-(3,4-dihydroxyphenyl)-L-alanine (L-DOPA), L-histidine, and L-arginine as precursor models. After they are heated, the precursors become carbonized. Nitrogen-doped Cdots are subsequently extracted into N,N-dimethylformamide (DMF) from the carbogenic solid. A coreshell structure of Cdots with a carbon core and the oxygen-containing shell was observed. Nitrogen has different forms in N-Cdots and oxidized N-Cdots. The doped nitrogen and low oxidation level in N-Cdots improve their emission significantly. The N-Cdots show an emission with a nitrogen-content-dependent intensity and Cdot-size-dependent emission-peak wavelength. Imaging of HeLa cells, a human cervical cancer cell line, and HepG2 cells, a human hepatocellular liver carcinoma line, was observed with high resolution using N-Cdots as a probe and validates their use in imaging applications and their multicolor property in the living cell system.

Journal ArticleDOI
M. Ablikim, M. N. Achasov1, O. Albayrak2, D. J. Ambrose  +365 moreInstitutions (52)
TL;DR: E+e-→π+π-hc at center-of-mass energies from 3.90 to 4.42 GeV is studied by using data samples collected with the BESIII detector operating at the Beijing Electron Positron Collider and a distinct structure, referred to as Zc(4020), is observed in the π±hc mass spectrum.
Abstract: We study e(+)e(-) -> pi(+) pi(-)h(c) at center-of-mass energies from 3.90 to 4.42 GeV by using data samples collected with the BESIII detector operating at the Beijing Electron Positron Collider. The Born cross sections are measured at 13 energies and are found to be of the same order of magnitude as those of e(+)e(-) -> pi(+) pi(-) J/Psi but with a different line shape. In the pi(+/-)h(c) mass spectrum, a distinct structure, referred to as Z(c)(4020) is observed at 4. 02 GeV/c(2). The Z(c)(4020) carries an electric charge and couples to charmonium. A fit to the pi(+/-)h(c) invariant mass spectrum, neglecting possible interferences, results in a mass of (4022.9 +/- 0.8 +/- 2.7) MeV/c(2) and a width of (7.9 +/- 2.7 +/- 2.6) MeV for the Z(c)(4020), where the first errors are statistical and the second systematic. The difference between the parameters of this structure and the Z(c) (4025) observed in the D*(D) over bar* final state is within 1.5 sigma, but whether they are the same state needs further investigation. No significant Z(c)(3900) signal is observed, and upper limits on the Z(c)(3900) production cross sections in pi +/- h(c) at center-of-mass energies of 4.23 and 4.26 GeVare set.

Journal ArticleDOI
TL;DR: In this article, the performance of different closed-loop supply chains under different channel leadership is investigated. And the authors find that the retailer-led model gives the most effective CLSC and analytically reveal that the remanufacturing system's efficiency is highly related to a supply chain agent's proximity to the market.

Journal ArticleDOI
TL;DR: Urinary excretion was the major elimination route for short PFAAs, but for longer PFCAs, PFOS and PFHxS, other routes of excretion likely contribute to overall elimination.
Abstract: Perfluoroalkyl acids (PFAAs) are persistent and bioaccumulative compounds that have been associated with adverse health outcomes. In human blood, PFAAs exist as both linear and branched isomers, yet for most linear homologues, and for all branched isomers, elimination rates are unknown. Paired blood and urine samples (n = 86) were collected from adults in China. They were analyzed by a sensitive isomer-specific method that permitted the detection of many PFAAs in human urine for the first time. For all PFAAs except perfluoroundecanoate (PFUnA), levels in urine correlated positively with levels in blood. Perfluoroalkyl carboxylates (PFCAs) were excreted more efficiently than perfluoroalkane sulfonates (PFSAs) of the same carbon chain-length. In general, shorter PFCAs were excreted more efficiently than longer ones, but for PFSAs, perfluorooctanesulfonate (PFOS, a C8 compound) was excreted more efficiently than perfluorohexanesulfonate (PFHxS, a C6 compound). Among PFOS and perfluorooctanoate (PFOA) isomers, major branched isomers were more efficiently excreted than the corresponding linear isomer. A one-compartment model was used to estimate the biological elimination half-lives of PFAAs. Among all PFAAs, the estimated arithmetic mean elimination half-lives ranged from 0.5 ± 0.1 years (for one branched PFOA isomer, 5m-PFOA) to 90 ± 11 years (for one branched PFOS isomer, 1m-PFOS). Urinary excretion was the major elimination route for short PFCAs (C ≤ 8), but for longer PFCAs, PFOS and PFHxS, other routes of excretion likely contribute to overall elimination. Urinary concentrations are good biomarkers of the internal dose, and this less invasive strategy can therefore be used in future epidemiological and biomonitoring studies. The very long half-lives of long-chain PFCAs, PFHxS, and PFOS isomers in humans stress the importance of global and domestic exposure mitigation strategies.

Journal ArticleDOI
TL;DR: An overview of the synthesis and properties of various boronic acid-containing hydrogels, including macroscopic hydrogel, microgels and layer-by-layer self-assembled films are reviewed, with an emphasis on the design of various glucose sensors and self-regulated insulin delivery devices.
Abstract: Boronic acid-containing hydrogels are important intelligent materials. With the introduction of boronic acid functionality, these hydrogels exhibit a lot of interesting properties, such as glucose-sensitivity, reversibility and self-healing. These materials have found important applications in many areas, especially in biomedical areas. This paper aims to provide an overview of the current state of the art of the study in this area. We review the synthesis and properties of various boronic acid-containing hydrogels, including macroscopic hydrogels, microgels and layer-by-layer self-assembled films. Their applications were described, with an emphasis on the design of various glucose sensors and self-regulated insulin delivery devices. New development in this area was highlighted. Problems and the new directions were discussed.

Journal ArticleDOI
Xi Yang1, Fan Zhang1, Long Zhang1, Tengfei Zhang1, Yi Huang1, Yongsheng Chen1 
TL;DR: In this paper, a high performance graphene oxide-doped ion gel (P(VDF-HFP)-EMIMBF4-GO gel) is prepared by exploiting copolymer (poly(vinylidene fluoride-hexafluoro propylene), P(HFP)) as the polymer matrix, ionic liquid (1-ethyl-3-methylimidazolium tetrafluoroborate, EMIMBF 4) as the supporting electrolyte, and GO as the ionic conducting promoter.
Abstract: A high-performance graphene oxide (GO)-doped ion gel (P(VDF-HFP)-EMIMBF4-GO gel) is prepared by exploiting copolymer (poly(vinylidene fluoride-hexafluoro propylene), P(VDF-HFP)) as the polymer matrix, ionic liquid (1-ethyl-3-methylimidazolium tetrafluoroborate, EMIMBF4) as the supporting electrolyte, and GO as the ionic conducting promoter. This GO-doped ion gel demonstrates significantly improved ionic conductivity compared with that of pure ion gel without the addition of GO, due to the homogeneously distributed GO as a 3D network throughout the GO-doped ion gel by acting like a ion “highway” to facilitate the ion transport. With the incorporation of only a small amount of GO (1 wt%) in ion gel, there has been a dramatic improvement in ionic conductivity of about 260% compared with that of pure ion gel. In addition, the all-solid-state supercapacitor is fabricated and measured at room temperature using the GO-doped ion gel as gel polymer electrolyte, which demonstrates more superior electrochemical performance than the all-solid-state supercapacitor with pure ion gel and the conventional supercapacitor with neat EMIMBF4, in the aspect of smaller internal resistance, higher capacitance performance, and better cycle stability. These excellent performances are due to the high ionic conductivity, excellent compatibility with carbon electrodes, and long-term stability of the GO-doped ion gel.

Journal ArticleDOI
TL;DR: In this article, a function-oriented design of carbonyl compounds with multi-electron reactions as positive electrode materials for rechargeable lithium batteries is presented, showing that molecular orbital profiles and energetics can be applied for the prediction of carboxyl utilization and modulation of redox potentials.
Abstract: Organic carbonyl compounds are potentially low-cost, sustainable, and high energy density electrode materials, but are plagued by unsatisfactory active-site utilization, low discharge potentials and low rate discharge–charge performance in battery applications. We herein disclose a function-oriented design of carbonyl compounds with multi-electron reactions as positive electrode materials for rechargeable lithium batteries, showing that molecular orbital profiles and energetics can be applied for the prediction of carbonyl utilization and modulation of redox potentials. By embedding pre-aromatic 1,2-dicarbonyl moieties in the extended conjugated systems, the desirable molecules integrate all known stabilizing factors and enable full four-Li uptake. Remarkably, two new carbonyl electrodes, pyrene-4,5,9,10-tetraone and 1,10-phenanthroline-5,6-dione, deliver a reversible capacity of 360 mA h g−1 and an average working potential of 2.74 V, respectively, providing insights in designing high-energy organic positive electrodes of lithium batteries for efficient energy storage and conversion.

Journal ArticleDOI
Shiwen Wang1, Lijiang Wang1, Kai Zhang1, Zhiqiang Zhu1, Zhanliang Tao1, Jun Chen1 
TL;DR: Charging the symmetrical cells with Li4C8H2O6 nanosheets as the initial active materials of both positive and negative electrodes produces all-organic LIBs with an average operation voltage of 1.8 V and an energy density of about 130 Wh kg(-1), enlightening the design and application of organic Li-reservoir compounds with nanostructures for all organic LIBs.
Abstract: Organic tetralithium salts of 2,5-dihydroxyterephthalic acid (Li4C8H2O6) with the morphologies of bulk, nanoparticles, and nanosheets have been investigated as the active materials of either positive or negative electrode of rechargeable lithium-ion batteries. It is demonstrated that, in the electrolyte of LiPF6 dissolved in ethylene carbonate (EC) and dimethyl carbonate (DMC), reversible two-Li-ion electrochemical reactions are taking place with redox Li4C8H2O6/Li2C8H2O6 at ∼2.6 V for a positive electrode and Li4C8H2O6/Li6C8H2O6 at ∼0.8 V for a negative electrode, respectively. In the observed system, the electrochemical performance of high to low order is nanosheets > nanoparticles > bulk. Remarkably, Li4C8H2O6 nanosheets show the discharge capacities of 223 and 145 mAh g–1 at 0.1 and 5 C rates, respectively. A capacity retention of 95% is sustained after 50 cycles at 0.1 C rate charge/discharge and room temperature. Moreover, charging the symmetrical cells with Li4C8H2O6 nanosheets as the initial activ...

Journal ArticleDOI
TL;DR: Investigation of a mechanism by which metallic particles are attracted and trapped by plasmonic tweezers when surface plasmons are excited and focused by a radially polarized beam in a high-numerical-aperture microscopic configuration finds that it is the sum of both gradient and scattering forces acting in the same direction established by the strong coupling between the metallic particle and the highly focused plAsmonic field.
Abstract: Scattering forces in focused light beams push away metallic particles. Thus, trapping metallic particles with conventional optical tweezers, especially those of Mie particle size, is difficult. Here we investigate a mechanism by which metallic particles are attracted and trapped by plasmonic tweezers when surface plasmons are excited and focused by a radially polarized beam in a high-numerical-aperture microscopic configuration. This contrasts the repulsion exerted in optical tweezers with the same configuration. We believe that different types of forces exerted on particles are responsible for this contrary trapping behaviour. Further, trapping with plasmonic tweezers is found not to be due to a gradient force balancing an opposing scattering force but results from the sum of both gradient and scattering forces acting in the same direction established by the strong coupling between the metallic particle and the highly focused plasmonic field. Theoretical analysis and simulations yield good agreement with experimental results.