Niobium carbide MXene quantum dots(Nb2 C MQDs)derived from 2 D Nb2 CTx(MXene)are the rising-star material recently.Herein,a sulfur and nitrogen co-doped Nb2 C MQDs(S,N-MQDs)were synthesized through a hydrothermal meth...Niobium carbide MXene quantum dots(Nb2 C MQDs)derived from 2 D Nb2 CTx(MXene)are the rising-star material recently.Herein,a sulfur and nitrogen co-doped Nb2 C MQDs(S,N-MQDs)were synthesized through a hydrothermal method.The obtained Nb2 C MQDs have excellent green fluorescence with a quantum yield(QY)of 17.25%.In addition,they exhibited excitatio n-dependent photoluminescence,antiphotobleaching and dispersion stability.They emit light at 520 nm when excited at 390 nm.The Nb2 C MQDs could be successfully applied to copper ion detection with detection limit of 2μmol/L and Caco-2 cells imaging.展开更多
CuInS_(2)quantum-dot(CIS QD)-modified g-C_(3)N_(4)(CN)catalysts(CIS/CN)were prepared with the aid of an in-situ growth process.The as-obtained photocatalysts were explored by measuring their crystallinity,surface morp...CuInS_(2)quantum-dot(CIS QD)-modified g-C_(3)N_(4)(CN)catalysts(CIS/CN)were prepared with the aid of an in-situ growth process.The as-obtained photocatalysts were explored by measuring their crystallinity,surface morphology,binding energy and light absorption activity.The photocatalytic efficiency of the pho-tocatalysts was evaluated through photocatalytic water splitting for hydrogen production and tetracycline(TC)antibiotic degradation under the simulated solar light and visible light respectively.The optimized sample(10CIS/CN)showed the best photocatalytic activity:producing 102.4μmol g^(-1)h^(-1)of hydrogen in 1 h,or degrading 52.16%of TC in 120 min,which were respectively 48 or 3.4 times higher than the photocatalytic activity of CN itself.The enhancement in the efficiency of the composite system was prin-cipally accredited to the enlargement of light absorption,the more effective in charge transfer and the dropping of the charge carrier pair recombination through a formed S-scheme heterojunctional interface.This work is an effort to adjust CN-based polysulfide QD for speedy photocatalysis.The enriched photo-catalytic activity grants a new sense for adjusting the optical properties of CN.展开更多
In this work,molybdenum disulfide quantum dots(MoS2 QDs) were firstly prepared by hydrothermal method using sodium molybdate and glutathione as precursors,and applied in ascorbic acid detection.When joining MnO2 nan...In this work,molybdenum disulfide quantum dots(MoS2 QDs) were firstly prepared by hydrothermal method using sodium molybdate and glutathione as precursors,and applied in ascorbic acid detection.When joining MnO2 nanosheets into MoS2 QDs solution,they produced an obvious fluorescence quenching,which should be due to inner filter effect(IFE).Meanwhile,the fluorescent probe was formed,Interestingly,we found that this quenching phenomenon disappeared with the addition of ascorbic acid,In other words,the fluorescence gradually restored.This recovery phenomenon is mainly due to the reduction effect of ascorbic acid for MnO2 nanosheets.Under the optimum conditions,the limit of detection(LOD) of 39 nmol/L for ascorbic acid was achieved with a linear range of 0.33-5.00 μmol/L.The repeatability was better than 5.0% for ascorbic acid in both standard and fruit samples(n = 3).Moreover,the as-fabricated fluorescent sensing system was successfully employed to detect the ascorbic acid levels in hawthorn and jujube with satisfactory results.展开更多
Ultra-small MoS_(2) quantum dots(QDs)with an average size of 2.48 nm coated on Au nanoparticles with a core-satellite structure(Au/MoS_(2) QDs)are successfully prepared by a self-assembly strategy through the strong b...Ultra-small MoS_(2) quantum dots(QDs)with an average size of 2.48 nm coated on Au nanoparticles with a core-satellite structure(Au/MoS_(2) QDs)are successfully prepared by a self-assembly strategy through the strong bonding between Au and S.Benefited from the unique structure,the Au/MoS_(2) QDs hybrid exhibits outstanding electrocatalytic performance toward hydrogen evolution reaction(HER).The Au/MoS_(2) QDs hybrid needs overpotentials of 112,146,and 206 mV to approach current densities of 10,20,and 50 mA·cm^(−2) in 0.5 mol·L^(−1) H_(2)SO_(4)(pH=0.3),respectively.And a low Tafel slope(83 mV·dec^(−1))is obtained.The catalyst also displays satisfactory stability and durability,indicating a negligible current density loss after 20 h of electrolysis.The high hydrogen generation activities and stability are attributed to the great number of active sites,high conductivity and synergistic effects between gold nanoparticles(Au NPs)and MoS_(2) QDs.Last but not least,this strategy opens up a favorable way to combine MoS_(2) QDs with other metals.展开更多
The strong anisotropic electrical properties of one-dimensional(1 D) nanostructure semiconductors,especially the anisotropic carrier transport, have a negative and significant influence on the performance of solar cel...The strong anisotropic electrical properties of one-dimensional(1 D) nanostructure semiconductors,especially the anisotropic carrier transport, have a negative and significant influence on the performance of solar cells if the nanostructures have random orientation. Considering the advantages of nanorod solar cells in carrier transport, we have achieved growth of vertically aligned Sb_(2)Se_(3) nanorod array with highly(hk1) orientation on Cd S substrate, and constructed superstrate nanorod solar cells for the first time. The Sb_(2)Se_(3) nanorod array solar cells exhibit the more efficient and long-range carrier transport in vertical direction. Furthermore, in order to suppress interface recombination, a CuInSe_(2) quantum dots(QDs) sensitizer has been applied to fill the volume between the nanorods completely, thus forming an interpenetrating nanocomposite structure. The CuInSe_(2) QDs can harvest additional light by absorption of visible light and contribute photocurrent. Meantime, the QDs function as a hole transport material and thus reduce the dependence of lateral transport. Consequently, the interpenetrating nanocomposite CuInSe_(2) / Sb_(2)Se_(3) solar cells display a power conversion efficiency of 7.54% with significant enhancements in the short-circuit current density and open-circuit voltage over pure Sb_(2)Se_(3) nanorod cells. This is the highest efficiency for superstrate solar cells based on Sb_(2)Se_(3) nanorod arrays.展开更多
Objective:To explore the protective effects of anthrahydroquinone-2,6-disulfonate(AH_(2)QDS)on the kidneys of paraquat(PQ)poisoned rats via the apelin-APJ pathway.Methods:Male Sprague Dawley rats were divided into fou...Objective:To explore the protective effects of anthrahydroquinone-2,6-disulfonate(AH_(2)QDS)on the kidneys of paraquat(PQ)poisoned rats via the apelin-APJ pathway.Methods:Male Sprague Dawley rats were divided into four experimental groups:control,PQ,PQ+sivelestat,and PQ+AH_(2)QDS.The PQ+sivelestat group served as the positive control group.The model of poisoning was established via intragastric treatment with a 20%PQ pesticide solution at 200 mg/kg.Two hours after poisoning,the PQ+sivelestat group was treated with sivelestat,while the PQ+AH_(2)QDS group was given AH_(2)QDS.Six rats were selected from each group on the first,third,and seventh days after poisoning and dissected after anesthesia.The PQ content of the kidneys was measured using the sodium disulfite method.Hematoxylin-eosin staining of renal tissues was performed to detect pathological changes.Apelin expression in the renal tissues was detected using immunofluorescence.Western blotting was used to detect the expression levels of the following proteins in the kidney tissues:IL-6,TNF-α,apelin-APJ(the apelin-angiotensin receptor),NF-κB p65,caspase-1,caspase-8,glucose-regulated protein 78(GRP78),and the C/EBP homologous protein(CHOP).In in vitro study,a PQ toxicity model was established using human tubular epithelial cells treated with standard PQ.Twenty-four hours after poisoning,sivelestat and AH_(2)QDS were administered.The levels of oxidative stress in human renal tubular epithelial cells were assessed using a reactive oxygen species fluorescence probe.Results:The PQ content in the kidney tissues of the PQ group was higher than that of the PQ+AH_(2)QDS group.Hematoxylin-eosin staining showed extensive hemorrhage and congestion in the renal parenchyma of the PQ group.Vacuolar degeneration of the renal tubule epithelial cells,deposition of crescent-like red staining material in renal follicles,infiltration by a few inflammatory cells,and a small number of cast formation were also observed.However,these pathological changes were less severe in the PQ+s展开更多
基金the National Nature Science Foundation of China(No.31340014)the Youth Development Project of Medical Technologyin Army(No.13QNP166)+1 种基金the Key Research and Development Program of Science and Technology Department of Sichuan Province(No.2019YFS0514)Funds for the Construction of Master’s Degree Granting Units in Guangxi Zhuang Autonomous Region in 2020 for the support。
文摘Niobium carbide MXene quantum dots(Nb2 C MQDs)derived from 2 D Nb2 CTx(MXene)are the rising-star material recently.Herein,a sulfur and nitrogen co-doped Nb2 C MQDs(S,N-MQDs)were synthesized through a hydrothermal method.The obtained Nb2 C MQDs have excellent green fluorescence with a quantum yield(QY)of 17.25%.In addition,they exhibited excitatio n-dependent photoluminescence,antiphotobleaching and dispersion stability.They emit light at 520 nm when excited at 390 nm.The Nb2 C MQDs could be successfully applied to copper ion detection with detection limit of 2μmol/L and Caco-2 cells imaging.
基金supported by National Natural Science Foundation of China(Nos.52272287,22268003 and 22202138)Project from Yunnan Province(Nos.202301AT070027,202305AF150116)Development Fund from Dali University(No.KY2296129740).
文摘CuInS_(2)quantum-dot(CIS QD)-modified g-C_(3)N_(4)(CN)catalysts(CIS/CN)were prepared with the aid of an in-situ growth process.The as-obtained photocatalysts were explored by measuring their crystallinity,surface morphology,binding energy and light absorption activity.The photocatalytic efficiency of the pho-tocatalysts was evaluated through photocatalytic water splitting for hydrogen production and tetracycline(TC)antibiotic degradation under the simulated solar light and visible light respectively.The optimized sample(10CIS/CN)showed the best photocatalytic activity:producing 102.4μmol g^(-1)h^(-1)of hydrogen in 1 h,or degrading 52.16%of TC in 120 min,which were respectively 48 or 3.4 times higher than the photocatalytic activity of CN itself.The enhancement in the efficiency of the composite system was prin-cipally accredited to the enlargement of light absorption,the more effective in charge transfer and the dropping of the charge carrier pair recombination through a formed S-scheme heterojunctional interface.This work is an effort to adjust CN-based polysulfide QD for speedy photocatalysis.The enriched photo-catalytic activity grants a new sense for adjusting the optical properties of CN.
基金financially supported by National Nature Science Foundation of China (No. 21475053)
文摘In this work,molybdenum disulfide quantum dots(MoS2 QDs) were firstly prepared by hydrothermal method using sodium molybdate and glutathione as precursors,and applied in ascorbic acid detection.When joining MnO2 nanosheets into MoS2 QDs solution,they produced an obvious fluorescence quenching,which should be due to inner filter effect(IFE).Meanwhile,the fluorescent probe was formed,Interestingly,we found that this quenching phenomenon disappeared with the addition of ascorbic acid,In other words,the fluorescence gradually restored.This recovery phenomenon is mainly due to the reduction effect of ascorbic acid for MnO2 nanosheets.Under the optimum conditions,the limit of detection(LOD) of 39 nmol/L for ascorbic acid was achieved with a linear range of 0.33-5.00 μmol/L.The repeatability was better than 5.0% for ascorbic acid in both standard and fruit samples(n = 3).Moreover,the as-fabricated fluorescent sensing system was successfully employed to detect the ascorbic acid levels in hawthorn and jujube with satisfactory results.
基金This work was financially supported by the National Natural Science Foundation of China(Grant No.21765016)Ningxia,leading scientific and technological innovation talents project(Grant No.KJT2018002)+1 种基金Natural Science Foundation of Ningxia(Grant No.2018AAC03012)First-rate Discipline Construction Project of Ningxia(Grant No.NXYLXK2017A04).
文摘Ultra-small MoS_(2) quantum dots(QDs)with an average size of 2.48 nm coated on Au nanoparticles with a core-satellite structure(Au/MoS_(2) QDs)are successfully prepared by a self-assembly strategy through the strong bonding between Au and S.Benefited from the unique structure,the Au/MoS_(2) QDs hybrid exhibits outstanding electrocatalytic performance toward hydrogen evolution reaction(HER).The Au/MoS_(2) QDs hybrid needs overpotentials of 112,146,and 206 mV to approach current densities of 10,20,and 50 mA·cm^(−2) in 0.5 mol·L^(−1) H_(2)SO_(4)(pH=0.3),respectively.And a low Tafel slope(83 mV·dec^(−1))is obtained.The catalyst also displays satisfactory stability and durability,indicating a negligible current density loss after 20 h of electrolysis.The high hydrogen generation activities and stability are attributed to the great number of active sites,high conductivity and synergistic effects between gold nanoparticles(Au NPs)and MoS_(2) QDs.Last but not least,this strategy opens up a favorable way to combine MoS_(2) QDs with other metals.
基金National Natural Science Foundation of China(21767009)China Scholarship Council(201808420149)+1 种基金Hubei Key Laboratory of Biological Resources Protection and Utilization(PKLHB1908)Undergraduate Innovation Program(201910517006)
基金financially supported by the National Key R&D Program of China (Grant No. 2019YFB1503400)the National Natural Science Foundation of China (Grant No. 61804064)the Natural Science Foundation of Guangdong Province (Grant No.2019A1515011616)。
文摘The strong anisotropic electrical properties of one-dimensional(1 D) nanostructure semiconductors,especially the anisotropic carrier transport, have a negative and significant influence on the performance of solar cells if the nanostructures have random orientation. Considering the advantages of nanorod solar cells in carrier transport, we have achieved growth of vertically aligned Sb_(2)Se_(3) nanorod array with highly(hk1) orientation on Cd S substrate, and constructed superstrate nanorod solar cells for the first time. The Sb_(2)Se_(3) nanorod array solar cells exhibit the more efficient and long-range carrier transport in vertical direction. Furthermore, in order to suppress interface recombination, a CuInSe_(2) quantum dots(QDs) sensitizer has been applied to fill the volume between the nanorods completely, thus forming an interpenetrating nanocomposite structure. The CuInSe_(2) QDs can harvest additional light by absorption of visible light and contribute photocurrent. Meantime, the QDs function as a hole transport material and thus reduce the dependence of lateral transport. Consequently, the interpenetrating nanocomposite CuInSe_(2) / Sb_(2)Se_(3) solar cells display a power conversion efficiency of 7.54% with significant enhancements in the short-circuit current density and open-circuit voltage over pure Sb_(2)Se_(3) nanorod cells. This is the highest efficiency for superstrate solar cells based on Sb_(2)Se_(3) nanorod arrays.
基金National Natural Science Foundation of China(No.81960351)Social Development Key Project of Hainan Province(No.ZDYF2019125)Hainan Provincial Natural Science Foundation of China(820QN398)Hainan Province Clinical Medical Center.
文摘Objective:To explore the protective effects of anthrahydroquinone-2,6-disulfonate(AH_(2)QDS)on the kidneys of paraquat(PQ)poisoned rats via the apelin-APJ pathway.Methods:Male Sprague Dawley rats were divided into four experimental groups:control,PQ,PQ+sivelestat,and PQ+AH_(2)QDS.The PQ+sivelestat group served as the positive control group.The model of poisoning was established via intragastric treatment with a 20%PQ pesticide solution at 200 mg/kg.Two hours after poisoning,the PQ+sivelestat group was treated with sivelestat,while the PQ+AH_(2)QDS group was given AH_(2)QDS.Six rats were selected from each group on the first,third,and seventh days after poisoning and dissected after anesthesia.The PQ content of the kidneys was measured using the sodium disulfite method.Hematoxylin-eosin staining of renal tissues was performed to detect pathological changes.Apelin expression in the renal tissues was detected using immunofluorescence.Western blotting was used to detect the expression levels of the following proteins in the kidney tissues:IL-6,TNF-α,apelin-APJ(the apelin-angiotensin receptor),NF-κB p65,caspase-1,caspase-8,glucose-regulated protein 78(GRP78),and the C/EBP homologous protein(CHOP).In in vitro study,a PQ toxicity model was established using human tubular epithelial cells treated with standard PQ.Twenty-four hours after poisoning,sivelestat and AH_(2)QDS were administered.The levels of oxidative stress in human renal tubular epithelial cells were assessed using a reactive oxygen species fluorescence probe.Results:The PQ content in the kidney tissues of the PQ group was higher than that of the PQ+AH_(2)QDS group.Hematoxylin-eosin staining showed extensive hemorrhage and congestion in the renal parenchyma of the PQ group.Vacuolar degeneration of the renal tubule epithelial cells,deposition of crescent-like red staining material in renal follicles,infiltration by a few inflammatory cells,and a small number of cast formation were also observed.However,these pathological changes were less severe in the PQ+s