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)functionaliz...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.展开更多
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 fa...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.展开更多
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 ...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.展开更多
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...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.展开更多
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 remai...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.展开更多
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...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.展开更多
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 therapeu...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.展开更多
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_(...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.展开更多
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 im...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.展开更多
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 c...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.展开更多
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 differen...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.展开更多
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,bi...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.展开更多
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)...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.展开更多
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 electroly...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].展开更多
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...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.展开更多
基金supported by the National Key R&D Program of China(2020YFA0710000)the National Natural Science Foundation of China(22122901,21902047)+1 种基金the Provincial Natural Science Foundation of Hunan(2020JJ5045,2021JJ20024,2021RC3054)the Shenzhen Science and Technology Program(JCYJ20210324140610028)。
文摘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.
基金supported by the National Key R&D Program of China(2021YFA1500900,2020YFA0710000)the National Natural Science Foundation of China(22172047,22002039,21825201 and U19A2017)+3 种基金the Provincial Natural Science Foundation of Hunan(2021JJ30089,2016TP1009 and 2020JJ5045)the China Postdoctoral Science Foundation(2019M662759,2020M682541 and 2020M682549)the Shenzhen Science and Technology Program(JCYJ20210324122209025)the Changsha Municipal Natural Science Foundation(kq2107008 and kq2007009)。
文摘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.
基金supported by the National Key R&D Program of China(grant no.2020YFA0710000)the National Natural Science Foundation of China(grant no.22122901)+1 种基金the Provincial Natural Science Foundation of Hunan(grant nos.2021JJ0008,2021JJ20024,2021RC3054,and 2020JJ5045)the Shenzhen Science and Technology Program(grant no.JCYJ20210324140610028).
文摘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.
基金Hunan Provincial Grant for Innovative Province Construction,Grant/Award Number:2019RS2023Science and Technology Innovation Program of Hunan Province,Grant/Award Number:2020RC5033+4 种基金Shenzhen Science and Technology Program,Grant/Award Number:RCJC20200714114434015National Natural Science Foundation of China,Grant/Award Numbers:51922039,T2122011Natural science foundation of Hunan Province,Grant/Award Number:2020JJ3003Guangdong Basic and Applied Basic Research Foundation,Grant/Award Number:2020A1515110786National Key Research and Development Program of China,Grant/Award Number:2020YFC1807302。
文摘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.
基金the National Natural Science Foundation of China (Nos.22375059, 22005133, 51922039 and52273174)Shenzhen Science and Technology Program (No.RCJC20200714114434015)+1 种基金Science and Technology Innovation Program of Hunan Province (No.2020RC5033)National Key Research and Development Program of China (No.2020YFC1807302) for financial support。
文摘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.
基金supported by the National Natural Science Foundation of China (22322902,U22A20396,22102052,22309050,and 22211540385)the National Key Research and Development Program of China (2021YFA1502000)+3 种基金the Science and Technology Innovation Program of Hunan Province (2021RC3065)Jiebang Guashuai Project of Changsha City (kq2301009)Shenzhen Science and Technology Program (JCYJ20210324120800002,JCYJ20220818100012025,and JCYJ20230807122007015)China Postdoctoral Science Foundation (2023T160205)。
基金supported by the National Natural Science Foundation of China (Nos. 21701043, 21573066, 51402100)the Provincial Natural Science Foundation of Hunan (Nos 2016JJ1006, 2016TP1009)the Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province and Shenzhen Science and Technology Program (No JCYJ20170306141659388)
文摘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.
基金supported by the National Natural Science Foundation of China(No.31670997)the Natural Science Foundation of Hunan Province(No.2015JJ1007)the Basic Research Program of Shenzhen City(No.JCYJ20160530193417959)
文摘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.
基金supported by the National Natural Science Foundation of China(Grant Nos.51872086,62174051,51991340,and 51991343)the Natural Science Foundation of Hunan Province(Grant No.2020JJ1001)+2 种基金the Hunan Province“Huxiang Talents”Project(Grant No.2021RC3038)the Double First-Class Initiative of Hunan University(Grant No.531109100004)the Shenzhen Basic Research Project(Grant No.JCYJ20210324142012035)。
文摘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.
基金supported by the National Key R&D Program of China(2020YFA0710000)the National Natural Science Foundation of China(22122901,21902047)+1 种基金the Natural Science Foundation of Hunan Province(2020JJ5045,2021JJ20024,2021RC3054)the Shenzhen Science and Technology Program(JCYJ20210324140610028)。
文摘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.
基金financially supported by the National Natural Science Foundation of China (Nos.62074054 and U21A20497)the Natural Science Foundation of Hunan Province (Nos.2018RS053,2019GK2245 and 2020JJ1002)Shenzhen Science and Technology Innovation Commission (No. RCYX20200714114537036)
文摘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.
基金This study was funded by the National Natural Scientific Foundation of China(31670997)Natural Science Foundation of Hunan Province(2015JJ1007)Basic Research Program of Shenzhen City(JCYJ20160530193417959)。
文摘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.
基金supported by the National Key Research and Development Program of China(2020YFA0710000)the National Natural Science Foundation of China(22122901)+1 种基金the Natural Science Foundation of Hunan Province(2021JJ20024,2021JC0008,and 2021RC3054)the Shenzhen Science and Technology Program(JCYJ20210324140610028)。
文摘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.
基金supported by the Fundamental Research Funds for the Central Universities (531107051102)the National Natural Science Foundation of China (51402100, 21573066, 21522305)+1 种基金the Provincial Natural Science Foundation of Hunan (2016TP1009)the Shenzhen Discovery Funding (JCYJ20170306141659388)
文摘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.
基金supported by the National Natural Science Foundation of China (21701043, 21573066, and 51402100)the Provincial Natural Science Foundation of Hunan (2016JJ1006 and 2016TP1009)the Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province and Shenzhen Science and Technology Program (JCYJ20170306141659388)
基金supported by the National Key R&D Program of China(2020YFA0710000)the National Natural Science Foundation of China(22122901 and 21902047)+1 种基金the Natural Science Foundation of Hunan Province(2020JJ5045,2021JJ20024,and 2021RC3054)the Shenzhen Science and Technology Program(JCYJ20210324140610028)。
文摘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].
基金The authors thank the National Key Research and Development Program(No.2021YFA1200700)the National Natural Science Foundation of China(Grant Nos.62074054 and U21A20497)+1 种基金the Natural Science Foundation of Hunan Province(Nos.2019GK2245 and 2020JJ1002)Shenzhen Science and Technology Innovation Commission(No.RCYX20200714114537036)for financial support.The work was also supported by the Fundamental Research Funds for the Central Universities.
文摘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.