Showing papers by "Nankai University published in 2014"
TL;DR: This research presents a new generation of state-of-the-art materials for bioorganic and non-volatile organometallic research that combines high-performance liquid chromatography and high-tech materials for organic synthesis.
Abstract: Beijing National Laboratory of Molecular Sciences (BNLMS) and Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry and Green Chemistry Center, Peking University, 202 Chengfu Road, 098#, Beijing 100871, China State Key Laboratory of Organometallic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 200060, China
830 citations
TL;DR: MoS2 nanoflowers with expanded interlayer spacing of the (002) plane were synthesized and used as high-performance anode in Na-ion batteries and hold promise for rechargeable Na(+) batteries.
Abstract: MoS2 nanoflowers with expanded interlayer spacing of the (002) plane were synthesized and used as high-performance anode in Na-ion batteries. By controlling the cut-off voltage to the range of 0.4–3 V, an intercalation mechanism rather than a conversion reaction is taking place. The MoS2 nanoflower electrode shows high discharge capacities of 350 mAh g−1 at 0.05 A g−1, 300 mAh g−1 at 1 A g−1, and 195 mAh g−1 at 10 A g−1. An initial capacity increase with cycling is caused by peeling off MoS2 layers, which produces more active sites for Na+ storage. The stripping of MoS2 layers occurring in charge/discharge cycling contributes to the enhanced kinetics and low energy barrier for the intercalation of Na+ ions. The electrochemical reaction is mainly controlled by the capacitive process, which facilitates the high-rate capability. Therefore, MoS2 nanoflowers with expanded interlayers hold promise for rechargeable Na-ion batteries.
720 citations
TL;DR: A small molecule named DR3TSBDT with dialkylthiol-substituted benzo[1,2-b:4,5-b']dithiophene (BDT) as the central unit was designed and synthesized for solution-processed bulk-heterojunction solar cells.
Abstract: A small molecule named DR3TSBDT with dialkylthiol-substituted benzo[1,2-b:4,5-b′]dithiophene (BDT) as the central unit was designed and synthesized for solution-processed bulk-heterojunction solar cells. A notable power conversion efficiency of 9.95% (certified 9.938%) has been achieved under AM 1.5G irradiation (100 mW cm–2), with an average PCE of 9.60% based on 50 devices.
667 citations
TL;DR: The preparation of a transparent conductive electrode (TCE) based on a silver nanowire (AgNW) percolation network modified with graphene oxide (GO) enables the GO sheets to wrap around and solder the AgNW junctions and thus dramatically reduce the inter-nanowire contact resistance without heat treatment or high force pressing.
Abstract: Transparent conductive electrodes with high surface conductivity, high transmittance in the visible wavelength range, and mechanical compliance are one of the major challenges in the fabrication of stretchable optoelectronic devices. We report the preparation of a transparent conductive electrode (TCE) based on a silver nanowire (AgNW) percolation network modified with graphene oxide (GO). The monatomic thickness, mechanical flexibility, and strong bonding with AgNWs enable the GO sheets to wrap around and solder the AgNW junctions and thus dramatically reduce the inter-nanowire contact resistance without heat treatment or high force pressing. The GO-soldered AgNW network has a figure-of-merit sheet resistance of 14 ohm/sq with 88% transmittance at 550 nm. Its storage stability is improved compared to a conventional high-temperature annealed AgNW network. The GO-soldered AgNW network on polyethylene terephthalate films was processed from solutions using a drawdown machine at room temperature. When bent to...
571 citations
TL;DR: The remarkable electrochemical performance of 5-Sn/C was attributed to the effective combination of ultrasmall Sn nanoparticles, uniform distribution, and porous carbon network structure, which simultaneously solved the major problems of pulverization, loss of electrical contact, and particle aggregation facing Sn anode.
Abstract: In this Letter, we reported on the preparation and Li-ion battery anode application of ultrasmall Sn nanoparticles (∼5 nm) embedded in nitrogen-doped porous carbon network (denoted as 5-Sn/C). Pyrolysis of Sn(Salen) at 650 °C under Ar atmosphere was carried out to prepare N-doped porous 5-Sn/C with the BET specific surface area of 286.3 m2 g–1. The 5-Sn/C showed an initial discharge capacity of 1014 mAh g–1 and a capacity retention of 722 mAh g–1 after 200 cycles at the current density of 0.2 A g–1. Furthermore, a reversible capacity of ∼480 mAh g–1 was obtained at much higher current density of 5 A g–1. The remarkable electrochemical performance of 5-Sn/C was attributed to the effective combination of ultrasmall Sn nanoparticles, uniform distribution, and porous carbon network structure, which simultaneously solved the major problems of pulverization, loss of electrical contact, and particle aggregation facing Sn anode.
526 citations
TL;DR: This paper proposes Dekey, a new construction in which users do not need to manage any keys on their own but instead securely distribute the convergent key shares across multiple servers and demonstrates that Dekey incurs limited overhead in realistic environments.
Abstract: Data deduplication is a technique for eliminating duplicate copies of data, and has been widely used in cloud storage to reduce storage space and upload bandwidth. Promising as it is, an arising challenge is to perform secure deduplication in cloud storage. Although convergent encryption has been extensively adopted for secure deduplication, a critical issue of making convergent encryption practical is to efficiently and reliably manage a huge number of convergent keys. This paper makes the first attempt to formally address the problem of achieving efficient and reliable key management in secure deduplication. We first introduce a baseline approach in which each user holds an independent master key for encrypting the convergent keys and outsourcing them to the cloud. However, such a baseline key management scheme generates an enormous number of keys with the increasing number of users and requires users to dedicatedly protect the master keys. To this end, we propose Dekey , a new construction in which users do not need to manage any keys on their own but instead securely distribute the convergent key shares across multiple servers. Security analysis demonstrates that Dekey is secure in terms of the definitions specified in the proposed security model. As a proof of concept, we implement Dekey using the Ramp secret sharing scheme and demonstrate that Dekey incurs limited overhead in realistic environments.
511 citations
TL;DR: In this paper, a novel 2D boron structure with nonzero thickness was proposed based on an ab initio evolutionary structure search, which is considerably lower in energy than the recently proposed $\ensuremath{\alpha}$-sheet structure and its analogues.
Abstract: It has been widely accepted that planar boron structures, composed of triangular and hexagonal motifs are the most stable two-dimensional (2D) phases and likely precursors for boron nanostructures. Here we predict, based on an ab initio evolutionary structure search, a novel 2D boron structure with nonzero thickness, which is considerably, by $50\text{ }\text{ }\mathrm{meV}/\mathrm{atom}$, lower in energy than the recently proposed $\ensuremath{\alpha}$-sheet structure and its analogues. In particular, this phase is identified for the first time to have a distorted Dirac cone, after graphene and silicene the third elemental material with massless Dirac fermions. The buckling and coupling between the two sublattices not only enhance the energetic stability, but also are the key factors for the emergence of the distorted Dirac cone.
504 citations
TL;DR: In this article, the authors defined dynamic capability as the firms' potential to systematically solve problems, formed by its propensity to sense opportunities and threats, to make timely decisions, and to implement strategic decisions and changes efficiently to ensure the right direction.
465 citations
TL;DR: Recent work on the recognition and assembly properties unique to p-Sulfonatocalix[n]arenes and their potential biological applications is summarized, by this group and by other laboratories.
Abstract: ConspectusDevelopments in macrocyclic chemistry have led to supramolecular chemistry, a field that has attracted increasing attention among researchers in various disciplines. Notably, the discoveries of new types of macrocyclic hosts have served as important milestones in the field. Researchers have explored the supramolecular chemistry of several classical macrocyclic hosts, including crown ethers, cyclodextrins, calixarenes, and cucurbiturils. Calixarenes represent a third generation of supramolecular hosts after cyclodextrins and crown ethers. Easily modified, these macrocycles show great potential as simple scaffolds to build podand-like receptors. However, the inclusion properties of the cavities of unmodified calixarenes are not as good as those of other common macrocycles. Calixarenes require extensive chemical modifications to achieve efficient endo-complexation.p-Sulfonatocalix[n]arenes (SCnAs, n = 4–8) are a family of water-soluble calixarene derivatives that in aqueous media bind to guest mole...
460 citations
TL;DR: The synergistic effect of CoS2, graphene, and CNTs leads to unique coS2 /RGO-CNT nanoarchitectures, the HER activity of which is among the highest for non-noble metal electrocatalysts, showing 10 mA cm(-2) current density at about 142 mV overpotentials and a high electrochemical stability.
Abstract: Flexible three-dimensional (3D) nanoarchitectures have received tremendous interest recently because of their potential applications in wearable electronics, roll-up displays, and other devices. The design and fabrication of a flexible and robust electrode based on cobalt sulfide/reduced graphene oxide/carbon nanotube (CoS2 /RGO-CNT) nanocomposites are reported. An efficient hydrothermal process combined with vacuum filtration was used to synthesize such composite architecture, which was then embedded in a porous CNT network. This conductive and robust film is evaluated as electrocatalyst for the hydrogen evolution reaction. The synergistic effect of CoS2 , graphene, and CNTs leads to unique CoS2 /RGO-CNT nanoarchitectures, the HER activity of which is among the highest for non-noble metal electrocatalysts, showing 10 mA cm(-2) current density at about 142 mV overpotentials and a high electrochemical stability.
420 citations
TL;DR: This work proposes a new Secure Outsourced ABE system, which supports both secure outsourced key-issuing and decryption and proposes an outsourced ABE construction which provides checkability of the outsourced computation results in an efficient way.
Abstract: Attribute-Based Encryption (ABE) is a promising cryptographic primitive which significantly enhances the versatility of access control mechanisms. Due to the high expressiveness of ABE policies, the computational complexities of ABE key-issuing and decryption are getting prohibitively high. Despite that the existing Outsourced ABE solutions are able to offload some intensive computing tasks to a third party, the verifiability of results returned from the third party has yet to be addressed. Aiming at tackling the challenge above, we propose a new Secure Outsourced ABE system, which supports both secure outsourced key-issuing and decryption. Our new method offloads all access policy and attribute related operations in the key-issuing process or decryption to a Key Generation Service Provider (KGSP) and a Decryption Service Provider (DSP), respectively, leaving only a constant number of simple operations for the attribute authority and eligible users to perform locally. In addition, for the first time, we propose an outsourced ABE construction which provides checkability of the outsourced computation results in an efficient way. Extensive security and performance analysis show that the proposed schemes are proven secure and practical.
TL;DR: The results reveal a mechanistic signaling pathway linking mitochondria-damaging signals to the dephosphorylation of FUNDC1 by PGAM5, which ultimately induces mitophagy.
TL;DR: It is shown that FUNDC1 regulates ULK1 recruitment to damaged mitochondria, where FUNDC 1 phosphorylation by ULK 1 is crucial for mitophagy.
Abstract: Autophagy eliminates dysfunctional mitochondria in an intricate process known as mitophagy. ULK1 is critical for the induction of autophagy, but its substrate(s) and mechanism of action in mitophagy remain unclear. Here, we show that ULK1 is upregulated and translocates to fragmented mitochondria upon mitophagy induction by either hypoxia or mitochondrial uncouplers. At mitochondria, ULK1 interacts with FUNDC1, phosphorylating it at serine 17, which enhances FUNDC1 binding to LC3. A ULK1-binding-deficient mutant of FUNDC1 prevents ULK1 translocation to mitochondria and inhibits mitophagy. Finally, kinase-active ULK1 and a phospho-mimicking mutant of FUNDC1 rescue mitophagy in ULK1-null cells. Thus, we conclude that FUNDC1 regulates ULK1 recruitment to damaged mitochondria, where FUNDC1 phosphorylation by ULK1 is crucial for mitophagy.
TL;DR: A graphene-based layered porous carbon material for the impregnation of sulfur as cathode for Li-S battery demonstrates a better electrochemical performance and cycle stability compared with those of graphene/sulfur composites.
Abstract: Because of advantages such as excellent electronic conductivity, high theoretical specific surface area, and good mechanical flexibility, graphene is receiving increasing attention as an additive to improve the conductivity of sulfur cathodes in lithium–sulfur (Li–S) batteries. However, graphene is not an effective substrate material to confine the polysulfides in cathodes and stable the cycling. Here, we designed and synthesized a graphene-based layered porous carbon material for the impregnation of sulfur as cathode for Li–S battery. In this composite, a thin layer of porous carbon uniformly covers both surfaces of the graphene and sulfur is highly dispersed in its pores. The high specific surface area and pore volume of the porous carbon layers not only can achieve a high sulfur loading in highly dispersed amorphous state, but also can act as polysulfide reservoirs to alleviate the shuttle effect. When used as the cathode material in Li–S batteries, with the help of the thin porous carbon layers, the a...
TL;DR: In this paper, a macroporous electrospun polycaprolactone (PCL) scaffolds with thicker fibers (5-6μm) and larger pores (∼30 μm) were fabricated to enhance the vascular regeneration and remodeling process.
TL;DR: The use of Na4C8H2O6 as the initial active materials for both electrodes provided the first example of all-organic rocking-chair SIBs with an average operation voltage of 1.8 V and a practical energy density of about 65 Wh kg(-1) with excellent cycling.
Abstract: Developing organic compounds with multifunctional groups to be used as electrode materials for rechargeable sodium-ion batteries is very important. The organic tetrasodium salt of 2,5-dihydroxyterephthalic acid (Na(4)DHTPA; Na4C8H2O6), which was prepared through a green one-pot method, was investigated at potential windows of 1.6-2.8 V as the positive electrode or 0.1-1.8 Vas the negative electrode (vs. Na+/Na), each delivering compatible and stable capacities of ca. 180 mAhg(-1) with excellent cycling. A combination of electrochemical, spectroscopic and computational studies revealed that reversible uptake/removal of two Na+ ions is associated with the enolate groups at 1.6-2.8 V (Na2C8H2O6/Na4C8H2O6) and the carboxylate groups at 0.1-1.8 V (Na4C8H2O6/Na6C8H2O6). The use of Na4C8H2O6 as the initial active materials for both electrodes provided the first example of all-organic rocking-chair SIBs with an average operation voltage of 1.8 V and a practical energy density of about 65 Whkg(-1).
TL;DR: In this paper, the fundamental principles and applications of Mg-air batteries are introduced and the design of electrode materials both for anodes and cathodes for further performance improvement is discussed.
Abstract: Metal–air batteries are important power sources for electronics and vehicles because of their remarkable high theoretical energy density and low cost. In this paper, we introduce the fundamental principles and applications of Mg–air batteries. Recent progress in Mg or Mg alloys as anode materials and typical classes of air cathode catalysts for Mg–air batteries are reviewed. In the meantime, different compositions of the electrolyte are also compared. The design of electrode materials both for anodes and cathodes of Mg–air batteries is discussed for further performance improvement. It is noted that in the development of rechargeable Mg–air batteries, bi-functional catalysts with reversible oxygen reduction and evolution reactions are facing challenges and it is worthwhile devoting much effort to this.
TL;DR: This work successfully fabricated an all-solid-state lithium battery based on organic pillar[5]quinone (C35H20O10) cathode and composite polymer electrolyte (CPE) with a stable cyclability and favorable prospect for the device application with high capacity.
Abstract: The cathode capacity of common lithium ion batteries (LIBs) using inorganic electrodes and liquid electrolytes must be further improved. Alternatively, all-solid-state lithium batteries comprising the electrode of organic compounds can offer much higher capacity. Herein, we successfully fabricated an all-solid-state lithium battery based on organic pillar[5]quinone (C35H20O10) cathode and composite polymer electrolyte (CPE). The poly(methacrylate) (PMA)/poly(ethylene glycol) (PEG)-LiClO4-3 wt % SiO2 CPE has an optimum ionic conductivity of 0.26 mS cm–1 at room temperature. Furthermore, pillar[5]quinine cathode in all-solid-state battery rendered an average operation voltage of ∼2.6 V and a high initial capacity of 418 mAh g–1 with a stable cyclability (94.7% capacity retention after 50 cycles at 0.2C rate) through the reversible redox reactions of enolate/quinonid carbonyl groups, showing favorable prospect for the device application with high capacity.
TL;DR: In this article, a detailed analysis of the current situation, characteristics and, most important of all, the decision-making process of sustainable consumption behaviors (SCB) of the rural residents in China Data were gathered from surveys conducted in 35 different municipalities or counties, with a total of 1403 questionnaires randomly distributed in 50 villages among these 35 selected regions.
TL;DR: A measurement of the energy dependence of antineutrino disappearance at the Daya Bay reactor neutrino experiment is reported, supporting the three-flavor oscillation model.
Abstract: A measurement of the energy dependence of antineutrino disappearance at the Daya Bay reactor neutrino experiment is reported. Electron antineutrinos (ν¯_e) from six 2.9 GW_(th) reactors were detected with six detectors deployed in two near (effective baselines 512 and 561 m) and one far (1579 m) underground experimental halls. Using 217 days of data, 41 589 (203 809 and 92 912) antineutrino candidates were detected in the far hall (near halls). An improved measurement of the oscillation amplitude sin^2 2θ_(13) = 0.090^(+0.008)_(−0.009) and the first direct measurement of the ν¯e mass-squared difference |Δm2ee|=(2.59^(+0.19)_(−0.20))×10^−3 eV^2 is obtained using the observed ν¯_e rates and energy spectra in a three-neutrino framework. This value of |Δm^(2)_(ee)| is consistent with |Δm^(2)_(μμ)| measured by muon neutrino disappearance, supporting the three-flavor oscillation model.
TL;DR: It is found that RGPs progress through a coherent program in which their proliferative potential diminishes in a predictable manner, suggesting that progenitor behavior and histogenesis in the mammalian neocortex conform to a remarkably orderly and deterministic program.
TL;DR: In this article, 2D hexagonal nanoplates of -Fe2O3/graphene composites with relatively good distribution were synthesized for the first time using a simple, one-step,======template-free, hydrothermal method that achieves the effective reduction of the graphene oxide (GO) to graphene.
Abstract: There has been significant progress in the field of semiconductor photocatalysis, but it is still a
challenge to fabricate low-cost and high-activity photocatalysts because of safety issues and nonsecondary
pollution to the environment. Here, 2D hexagonal nanoplates of -Fe2O3/graphene
composites with relatively good distribution are synthesized for the first time using a simple, one-step,
template-free, hydrothermal method that achieves the effective reduction of the graphene oxide (GO) to
graphene and intimate and large contact interfaces of the -Fe2O3 nanoplates with graphene. The -
Fe2O3/graphene composites showed significantly enhancement in the photocatalytic activity compared
with the pure -Fe2O3 nanoplates. At an optimal ratio of 5 wt% graphene, 98% of Rhodamine (RhB) is
decomposed with 20 min of irradiation, and the rate constant of the composites is almost four times
higher than that of pure -Fe2O3 nanoplates. The decisive factors in improving the photocatalytic
performance are the intimate and large contact interfaces between 2D hexagonal -Fe2O3 nanoplates
and graphene, in addition to the high electron withdrawing/storing ability and the highconductivity of
reduced graphene oxide (RGO) formed during the hydrothermal reaction. The effective charge transfer
from -Fe2O3 nanoplates to graphene sheets is demonstrated by the significant weakening of
photoluminescence in -Fe2O3/graphene composites.
TL;DR: Extracellular DNA in sediment is a major ARG reservoir that could facilitate antibiotic resistance propagation, and chromosomally encoded 16S rRNA genes were undetectable after 8 weeks, suggesting higher persistence of plasmid-borne ARGs in river sediment.
Abstract: The propagation of antibiotic resistance genes (ARGs) represents a global threat to both human health and food security. Assessment of ARG reservoirs and persistence is therefore critical for devising and evaluating strategies to mitigate ARG propagation. This study developed a novel, internal standard method to extract extracellular DNA (eDNA) and intracellular DNA (iDNA) from water and sediments, and applied it to determine the partitioning of ARGs in the Haihe River basin in China, which drains an area of intensive antibiotic use. The concentration of eDNA was higher than iDNA in sediment samples, likely due to the enhanced persistence of eDNA when associated with clay particles and organic matter. Concentrations of sul1, sul2, tetW, and tetT antibiotic resistance genes were significantly higher in sediment than in water, and were present at higher concentrations as eDNA than as iDNA in sediment. Whereas ARGs (frequently located on plasmid DNA) were detected for over 20 weeks, chromosomally encoded 16S rRNA genes were undetectable after 8 weeks, suggesting higher persistence of plasmid-borne ARGs in river sediment. Transformation of indigenous bacteria with added extracellular ARG (i.e., kanamycin resistance genes) was also observed. Therefore, this study shows that extracellular DNA in sediment is a major ARG reservoir that could facilitate antibiotic resistance propagation.
TL;DR: In this paper, a NVP@C core-shell nanocomposite has been synthesized through a hydrothermal assisted sol-gel method, where ascorbic acid and polyethylene glycol 400 (PEG-400) were synergistically used to control the particle growth and provide the surface coating of conductive carbon.
Abstract: Na3V2(PO4)3 (NVP) is an attractive cathode material for sodium ion batteries due to its high theoretical energy density and stable three-dimensional (3D) NASICON structure. In this paper, a NVP@C core–shell nanocomposite has been synthesized through a hydrothermal assisted sol–gel method. Ascorbic acid and polyethylene glycol 400 (PEG-400) were synergistically used to control the particle growth and provide the surface coating of conductive carbon. The as-prepared nanocomposite was composed of a nanosized Na3V2(PO4)3 core with a typical size of ∼40 nm and a uniformly amorphous carbon shell with the thickness of a few nanometers. The electrode performance of the NVP@C core–shell nanocomposite as cathode for sodium ion batteries is investigated and compared with that of bare NVP and NVP/C. Among the samples examined, the NVP@C nanocomposite showed the best cycle life and rate capability. It rendered an initial capacity of 104.3 mA h g−1 at 0.5 C and 94.9 mA h g−1 at 5 C with a remarkable capacity retention of 96.1% after 700 cycles. Moreover, a full cell using the as-prepared nanocomposite as both the cathode and the anode active material has been successfully built, showing a reversible capacity of 90.9 mA h g−1 at 2 C with an output voltage of about 1.7 V and a specific energy density of about 154.5 W h kg−1. The enhanced electrode performance is attributed to the combination of particle downsizing and carbon coating, which can favor the migration of both electrons and ions.
TL;DR: A new type of edge state is found: one residing on the bearded edge that has never been predicted or observed in graphene, and can be classified as a Tamm-like state lacking any surface defect.
Abstract: The propagation of light in photonic crystals with a honeycomb structure mirrors the behaviour of charges in graphene, therefore allowing for the investigation of electronic properties that cannot otherwise be accessed in graphene itself. This approach is now used to predict unexpected edge states that localize in the bearded edges of hexagonal lattices.
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TL;DR: Wang et al. as discussed by the authors introduced a novel framework based on Recurrent Neural Networks (RNN), which directly models the dependency on user's sequential behaviors into the click prediction process through the recurrent structure in RNN.
Abstract: Click prediction is one of the fundamental problems in sponsored search. Most of existing studies took advantage of machine learning approaches to predict ad click for each event of ad view independently. However, as observed in the real-world sponsored search system, user's behaviors on ads yield high dependency on how the user behaved along with the past time, especially in terms of what queries she submitted, what ads she clicked or ignored, and how long she spent on the landing pages of clicked ads, etc. Inspired by these observations, we introduce a novel framework based on Recurrent Neural Networks (RNN). Compared to traditional methods, this framework directly models the dependency on user's sequential behaviors into the click prediction process through the recurrent structure in RNN. Large scale evaluations on the click-through logs from a commercial search engine demonstrate that our approach can significantly improve the click prediction accuracy, compared to sequence-independent approaches.
TL;DR: In this paper, a composite of magnetite nanoparticles (NPs) grown on reduced graphene oxide (rGO) has been synthesized by a facile hydrothermal technique without any surfactants or templates.
TL;DR: A novel organic-inorganic three-dimensional mesoporous graphite carbon nitride/BiOI (MCN/ biOI) heterojunction photocatalyst with excellent visible-light-driven photocatalytic performance was synthesized by a facile solvothermal method and used for degradation of bisphenol A (BPA) in water.
Abstract: A novel organic–inorganic three-dimensional (3D) mesoporous graphite carbon nitride/BiOI (MCN/BiOI) heterojunction photocatalyst with excellent visible-light-driven photocatalytic performance was synthesized by a facile solvothermal method and used for degradation of bisphenol A (BPA) in water. After hybridization with MCN, a heterojunction was formed and the photogenerated carriers could be effectively separated by the internal electric field built at the heterojunction interface. The photocatalytic and photoelectrochemical performance of BiOI were improved and much higher than pure BiOI and MCN. The best photocatalytic performance was achieved with MCN proportion of 10%, and the kobs was approximately 1.6 times of pure BiOI and 3.4 times of MCN under simulated solar light irradiation, respectively. The photocurrent intensity generated by 10%-MCN/BiOI electrode was about 1.5 and 2.0 times of those induced by BiOI and MCN under visible-light irradiation, respectively. The superoxide radical species were p...
TL;DR: In this paper, two 3D lanthanide metal-organic frameworks (Ln-MOFs) based on cubane-shaped [Ln4(μ3-OH)4]8+ clusters were successfully synthesized and fully characterized.
Abstract: Two new isostructural 3D lanthanide metal–organic frameworks (Ln-MOFs) {[Ln4(μ3-OH)4(BPDC)3(BPDCA)0.5(H2O)6]ClO4·5H2O}n (Ln = Tb (1) and Gd (2), BPDC2– = 3,3′-dicarboxylate-2,2′-dipyridine anion and BPDCA2– = biphenyl-4,4′-dicarboxylate anion) based on cubane-shaped [Ln4(μ3-OH)4]8+ clusters were successfully synthesized and fully characterized. There are two kinds of micropores with dimensions of 3.0 × 7.0 A2 along the b-axis and 4.5 × 5.5 A2 along the c-axis in the cationic framework. Ln-MOF 1 exhibits an intensive green luminescence triggered by the efficient antenna effect of ligands under UV light. Luminescent studies illustrate that Ln-MOF 1 could be an efficient multifunctional luminescent material for high-sensitivity sensing of small organic molecules, metal cations, and anions, especially for benzene and acetone, Cu2+, and CrO42–. The mechanism of the sensing properties was studied in detail as well. Additionally, this cationic framework also displays fast capture of pollutant CrO42– by anion exc...
TL;DR: In this paper, two types of porous cobalt manganese oxide nanowires with different structures have been successfully synthesized by thermal decomposition of organometallic compounds for the first time.
Abstract: Two types of porous cobalt manganese oxide nanowires (MnCo2O4 and CoMn2O4) with different structures have been successfully synthesized by thermal decomposition of organometallic compounds for the first time. Nitrilotriacetic acid (NA) was used as a chelating agent to coordinate Co(II) and Mn(II) ions in various molar ratios, in a hydrothermal condition. The microstructure of as-synthesized cobalt manganese oxides, composed of numerous nanoparticles, completely retains the 1D network structure of the Co–Mn–NA coordination precursors without structure collapse. Electrochemical properties of the cobalt manganese oxide materials have been tested for supercapacitors at room temperature. Both the MnCo2O4 and CoMn2O4 electrodes display the outstanding capacitive behaviors and superior electrochemical properties. The CoMn2O4 nanowire shows excellent capacitance and desirable rate performance (2108 F g−1 at 1 A g−1 and 1191 F g−1 at 20 A g−1) compared to that of the MnCo2O4 nanowire (1342 F g−1 at 1 A g−1 and 988 F g−1 at 20 A g−1). Electrochemical impedance spectra (EIS) results also reconfirm that the CoMn2O4 nanowires display more facile electrolyte diffusion and higher capacitor response frequency than MnCo2O4 nanowires. This can be ascribed to the facile electrolyte/OH− ion penetration and better Faradaic utilization of the electroactive surface sites that generated by the smaller particle size and higher surface area.