Sulfonic groups functionalized Zr-metal organic framework for highly catalytic transfer hydrogenation of furfural to furfuryl alcohol

The highly selective catalytic transfer hydrogenation(CTH)of furfural(FF)to furfuryl alcohol(FOL)is a significant route of biomass valorization.Herein,a series microporous Zr-metal organic framework(ZrMOF)functionalized by sulfonic groups are prepared.Based on the comprehensive structural characterizations by means of X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),N2 physisorption,Thermogravimetric(TG)and Fourier transformed infrared spectroscopy(FTIR),we find that sulfonic acid(–SO_(3)H)functional groups are tethered on the UIO-66 without affecting the structure of the framework.Systematic characterizations(NH_(3)-TPD,CO_(2)-TPD,and in-situ FTIR)demonstrate that modifying of sulfonic groups on UIO-66 results in the formation of stronger Lewis acidic-basic and Brnsted acidis sites.The cooperative role of the versatile Lewis acidic-basic and Brnsted acidic sites in 60%mol fraction of sulfonic acid-containing UIO-66(UIO-S_(0.6))retain high surface area and exhibit excellent catalytic performance of 94.7%FOL yield and 16.9 h^(-1).turnover number(TOF)under mild conditions.Kinetic experiments reveal that the activation energy of the CTH of furfural(FF)over UIO-S_(0.6) catalyst is as low as 50.8 k J mol^(-1).Besides,the hydrogen transfer mechanism is investigated through isotope labeling experiments,exhibiting that theβ-H in isopropanol is transferred to the a-C of FF by forming six-membered intermediates on the Lewis acidic-basic and Brnsted acidic sites of the UIO-S_(0.6),which is the rate-determining step in the formation of FOL.

Activation of iridium site by anchoring ruthenium atoms on defects for efficient anodic catalyst in polymer electrolyte membrane water electrolyzers

1.Introduction Hydrogen is an ideal energy carrier to tackle the energy crisis and greenhouse effect,because of its high energy density and low emission.The production,storage and transportation of hydrogen are key factors to the practical application of hydrogen energy.As the scientific and technological understanding of the electrochemical devices was advancing in the past few decades,water electrolyzers based on the proton exchange membrane (PEM) have attracted much focus for its huge potential on the production of hydrogen via water splitting.PEM electrolyzers use perfluorinated sulfonic acid (PFSA) based membranes as the electrolyte.

Anodic Electrosynthesis of Amide from Alcohol and Ammonia

Amide is essential in biologically active compounds,synthetic materials,and building blocks.However,conventional amide production relies on energyintensive consumption and activating agents that modulate processes to construct the C–N bond.Herein,for the first time,we have successfully realized the formation of amides at industrial current density via the anodic coelectrolysis of alcohol and ammonia under ambient conditions.We have proved thatmodulation of the interface microenvironment concentration of nucleophile by electrolyte engineering can regulate the reaction pathways of amides rather than acetic acids.The C-N coupling strategy can be further extended to the electrosynthesis of the long-chain and aryl-ring amide with high selectivity by replacing ammonia with amine.Our work opens up a vast store of information on the utilization of biomass alcohol for high-value N-containing chemicals via an electrocatalytic C-N coupling reaction.

Fluorogenic detection of mercury ion in aqueous environment using hydrogel-based AIE sensing films

A“turn-on”fluorescent sensing strategy was developed for ultrasensitive detection of heavy metal mercury ion(Hg2+)directly in water.It utilized an aqueous soluble aggregation-induced emission(AIE)-active probe,named 1,1,2,2-tetrakis(4-(1Htetrazol-5-yl)phenyl)ethene(TPE-4TA),composing of a luminescent tetraphenylene core and multiple anionic tetrazolate spawns.The probe retained dark when molecularly dissolved in water.However,mercury ions can ligate with multiple tetrazolate groups to form infinite coordination polymer particles spontaneously,thus inducing a fluorogenic AIE response for in situ analysis.Moreover,by embedding this AIE sensing molecules in a hydrophilic polyvinyl alcohol substrate,the resulting hydrogel film allowed in situ detection of Hg^(2+)on a laser-induced fluorescence analysis setup in aqueous environment.This strategy worked effectively in common aqueous environments with pH from 4 to 7.5 and showed high sensitivity(limit of detection down to 0.38 ppb/1.9 nM),good selectivity and a wide linearity range for quantification.This work may lead to a reliable and promising platform for on-site environmental water analysis.

Electron-transporting boron-doped polycyclic aromatic hydrocarbons:Facile synthesis and heteroatom doping positions-modulated optoelectronic properties

While heteroatom doping serves as a powerful strategy for devising novel polycyclic aromatic hydrocarbons(PAHs), the further fine-tuning of optoelectronic properties via the precisely altering of doping patterns remains a challenge. Herein, by changing the doping positions of heteroatoms in a diindenopyrene skeleton, we report two isomeric boron, sulfur-embedded PAHs, named Anti-B_(2)S_(2) and Syn-B_(2)S_(2), as electron transporting semiconductors. Detailed structure-property relationship studies revealed that the varied heteroatom positions not only change their physicochemical properties, but also largely affect their solid-state packing modes and Lewis base-triggered photophysical responses. With their low-lying frontier molecular orbital levels, n-type characteristics with electron mobilities up to 1.5 × 10^(-3)cm^(2)V^(-1)s^(-1)were achieved in solution-processed organic field-effect transistors. Our work revealed the critical role of controlling heteroatom doping patterns for designing advanced PAHs.

三合一设计策略促进超细PtNiW@WOx核壳纳米线氢氧化电催化剂的CO耐受性

铂(Pt)是质子交换膜燃料电池(PEMFCs)阳极氢氧化反应(HOR)中最先进的电催化剂.然而,Pt催化剂对CO(工业低成本氢燃料中的杂质)极度敏感从而中毒,这会引起器件性能的急剧衰退,导致器件运行成本高.因此,提高Pt催化剂的CO耐受性对PEMFCs的商业化推广至关重要.在此,我们设计合成了一种独特的PtNiW@WO_(x)核壳纳米线来提高Pt基催化剂对CO的耐受能力.机理研究表明,表面无定形的WO_(x)壳层可以作为分子围栏,在动力学上阻碍CO扩散到达Pt位点.在热力学上,Ni和W元素合金化产生的电子效应可以使Pt的d带中心降低,减弱CO在Pt位点上的化学吸附.此外,亲氧W元素可以加速水的解离,提供更多OH活性物种,促进CO的氧化脱附.因此,在1000ppm CO/H_(2)条件下,所设计的PtNiW@WO_(x)核壳纳米线催化剂表现出优异的HOR抗CO中毒性能,在4000 s后仍能保持超过90%的HOR电流密度,超过了原始的PtNi纳米线和目前报道的绝大多数Pt基催化剂.

First-principles study of methanol adsorption on heteroatom-doped phosphorene

First-principles calculations based on van der Waals(vdW) corrected density functional theory(DFT) are firstly employed to investigate the adsorption of methanol(CH_3OH) gas molecule on pristine and Xdoped phosphorene( =B, C, N and O). The CH_3OH gas molecule is placed on the top of different phosphorene surfaces, the whole adsorption systems are fully optimized by using Vienna ab initio simulation package(VASP). The calculation results demonstrate that both pristine and heteroatomdoped phosphorene are sensitive to CH_3OH gas molecule with a moderate adsorption energy and an excellent charge transfer. Among all the investigated adsorption configurations, CH_3OH gas molecule is physically absorbed on pristine phosphorene and heteroatom-doped phosphorene. The N and O doping improve the adsorption of phosphorene with CH_3OH gas molecule, while B and C doping are almost not beneficial compared to the pristine phosphorene. The results suggest that N-doped and O-doped phosphorene are ideal candidates used for CH_3OH gas sensing.

Characterization of synergistic anti-tumor effects of doxorubicin and p53 via graphene oxide-polyethyleneimine nanocarriers

Co-delivery of chemical drugs and therapeutic genes for synergistic therapy provides a promising strategy to treat devastating diseases. However, the real-time coordination patterns between chemical drugs and therapeutic genes remain poorly understood. Herein, the complexes of doxorubicin/graphene oxidepolyethyleneimine/p53 plasmid（Dox/GO-PEI/p53） were fabricated and employed to investigate the synergistic manner between Dox and p53 in the inhibition of He La cell growth. GO was conjugated with PEI to form the GO-PEI backbone as the delivery vector. The GO backbone provided surfaces with a high specific area to load Dox via the π-π stacking interaction, and was able to release Dox significantly faster at pH 5.0 than at pH 7.0, while the positively charged PEI section of GO-PEI could condense plasmids into GO-PEI/DNA nanoparticles via the electrostatic interaction. The nanoparticles efficiently mediated the transfection of DNA in He La cells, with lower cytotoxicity compared to PEI/DNA nanoparticles. Furthermore, the complexes of Dox/GO-PEI/p53 released Dox and expressed p53 gene in a sequential manner,and showed successive inhibition of the in vitro growth of He La cells. This type of drug/GO-PEI/DNA complex can be employed as a platform to investigate the coordination pattern between chemical drugs and therapeutic genes for tumor therapy.

Promoting the optoelectronic and ferromagnetic properties of Cr_(2)S_(3)nanosheets via Se doping

Doping can change the band structure of semiconductors,thereby affecting their electrical,optical,and magnetic properties.In this study,we describe the synthesis of two-dimensional(2D)Se-doped Cr_(2)S_(3)(Se-Cr_(2)S_(3))nanosheets using the chemical vapor deposition method.In these semiconductor nanosheets,the Se doping concentration can be controlled by tuning the Se/S mass ratio in the precursor.At the doping concentrations of 10.05%and 2.05%,the room temperature conductivity and mobility were increased by nearly 4 and 2 orders of magnitude,respectively.In addition,the response time of an ultrathin Se-Cr_(2)S_(3)photodetector was 200 times shorter than that of an undoped Cr_(2)S_(3)nanosheet photodetector.4.07%-Se-Cr_(2)S_(3)nanosheets show ferrimagnetic behavior with a Curie temperature of~200 K,which is 80 K higher than that of undoped Cr_(2)S_(3)nanosheets.A density functional theory calculation indicated that the Se doping can induce the formation of intercalated Cr vacancies in SeCr_(2)S_(3)and enhance its metallic characteristics.Our results demonstrated that Se-Cr_(2)S_(3)has significant potential in future electronic,optoelectronic,and spintronic devices.

Selective Electrocatalytic Hydrogenation of 5-Hydroxymethylfurfural to 2,5-Dihydroxymethylfuran on Bimetallic PdCu Alloy

2,5-dihydroxymethylfuran(DHMF),obtained from 5-hydroxymethylfurfural(HMF)by electrochemical method,is a promising building block for polymers.However,one challenge of this process is to reduce initial potential and improve catalytic selectivity.In this work,the PdCu bimetallic catalyst is prepared with an onset potential of-0.05 VRHE and a selectivity of 99%.Compared with the single Cu electrocatalyst,the adsorption of HMF and proton is improved by introducing of Pd,which is demonstrated by the electrochemical results and hydrogen production rate.This work provides an effective strategy to improve the selectivity of Cu-based electrocatalyst and builds a relationship between the adsorption capacity and the electrocatalytic performance.

Efficient p-doping of P3HT for hole transporting materials in perovskite solar cells

Developing hole transporting materials(HTMs)appropriate for large-area and high-performance perovskite solar cells(PSCs)is an important issue.In this work,we report using a widely used organic semiconductor P3 HT in combination with an efficient organic salt dopant trityl tetrakis(pentafluorophenyl)borate(TrTFPB)as HTM in PSCs.It is shown that the dopant can significantly enhance the conductivity of P3 HT while slightly change the film morphology.By doping P3 HT with different doping levels.

Inhibition of HeLa cell growth by doxorubicin-loaded and tuftsinconjugated arginate-PEG microparticles

In order to improve the release pattern of chemotherapy drug and reduce the possibility of drug resistance,poly(ethylene glycol amine)(PEG)-modified alginate microparticles(ALG-PEG MPs)were developed then two different mechanisms were employed to load doxorubicin(Dox):1)forming Dox/ALGPEG complex by electrostatic attractions between unsaturated functional groups in Dox and ALG-PEG;2)forming Dox-ALG-PEG complex through EDC-reaction between the amino and carboxyl groups in Dox and ALG,respectively.Additionally,tuftsin(TFT),a natural immunomodulation peptide,was conjugated to MPs in order to enhance the efficiency of cellular uptake.It was found that the Dox-ALG-PEGTFT MPs exhibited a significantly slower release of Dox than Dox/ALG-PEG-TFT MPs in neutral medium,suggesting the role of covalent bonding in prolonging Dox retention.Besides,the release of Dox from these MPs was pH-sensitive,and the release rate was observably increased at pH 6.5 compared to the case at pH 7.4.Compared with Dox/ALG-PEG MPs and Dox-ALG-PEG MPs,their counterparts further conjugated with TFT more efficiently inhibited the growth of HeLa cells over a period of 48 h,implying the effectiveness of TFT in enhancing cellular uptake of MPs.Over a period of 48 h,Dox-ALG-PEG-TFT MPs inhibited the growth of HeLa cells less efficiently than Dox/ALG-PEG-TFT MPs but the difference was not significant(p>0.05).In consideration of the prolonged and sustained release of Dox,Dox-ALGPEG-TFT MPs possess the advantages for long-term treatment.

生物质平台分子的电催化氧化

Energy depletion and environmental degradation caused by the continued consumption of fossil fuels have driven the development of renewable energy conversion.As one of the main components of global renewable energy,biomass from plants and waste(the regeneration is 170 billion tons per year)has become a rich resource for biofuels and chemical industries due to its fast regeneration,degradability and non-polluting nature.

Single-crystalline layered double hydroxides with rich defects and hierarchical structure by mild reduction for enhancing the oxygen evolution reaction

The oxygen evolution reaction(OER)with sluggish reaction kinetics and large overpotential is the critical reaction in water splitting that is promising for energy storage and conversion.Layered double hydroxides(LDHs),due to their unique lamellar structure and flexibility of chemical component,are very competing material candidates for OER.Herein,the morphology structure and the electronic structure of LDHs were simultaneously tuned to improve the OER catalytic activity by mild solvothermal reduction using ethylene glycol.The increased surface area,the introduction of oxygen vacancies and the construction of hierarchical structure greatly enhanced the electro-catalytic activity of LDHs for OER.The as-prepared LDHs showed a lower over-potential as low as 276 mV at a current density of 10 mA cm-2,and a small Tafel slope of 40.3 mV dec-1 accompanied with good stability.This work provides an efficient way to the design and optimization of advanced catalysts in the future.

具有痕量钴掺杂且暴露更多边缘活性的N,P共掺杂的多孔碳纳米片作为高效氧还原催化剂（英文）

本文使用有机分子配位聚合作用一步聚合、碳化、酸洗得到了一种N,P双掺杂碳材料.其具有痕量掺杂的金属钴、且具有更多活性边缘.X射线光电子能谱显示杂原子成功进入碳材料当中,并且发现酸洗后钴的信号非常低,证明酸洗后,材料表面形成非常多的孔,暴露出更多的边缘催化位点.制备的碳材料具有大量催化活性位点,因此表现出极其优异的电催化氧还原性能.另外,与Pt/C相比,制备的多孔碳材料还具有较好的抗毒性与稳定性,进一步显示了其在新能源电池领域的应用前景.

一种双极产氢电解系统

Hydrogen,a prospective green fuel with the advantages of high calorific value and no byproducts,is a main focus in the new energy area[1].Many mature ways to produce Hinclude reforming fossil fuels and water electrolysis.Reforming fossil fuels occupy the vast majority of hydrogen production because of their low cost.However,it is unsustainable and polluting[2].

Band-like transport in non-fullerene acceptor semiconductor Y6

The recently reported non-fullerene acceptor(NFA)Y6 has been extensively investigated for high-performance organic solar cells.However,its charge transport property and physics have not been fully studied.In this work,we acquired a deeper understanding of the charge transport in Y6 by fabricating and characterizing thin-film transistors(TFTs),and found that the electron mobility of Y6 is over 0.3-0.4 cm^(2)/(V⋅s)in top-gate bottom-contact devices,which is at least one order of magnitude higher than that of another well-known NFA ITIC.More importantly,we observed band-like transport in Y6 spin-coated films through temperature-dependent measurements on TFTs.This is particularly amazing since such transport behavior is rarely seen in polycrystalline organic semiconductor films.Further morphology characterization and discussions indicate that the band-like transport originates from the unique molecule packing motif of Y6 and the special phase of the film.As such,this work not only demonstrates the superior charge transport property of Y6,but also suggests the great potential of developing high-mobility n-type organic semiconductors,on the basis of Y6.