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1.
J Colloid Interface Sci ; 652(Pt B): 1394-1404, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37659308

RESUMO

Transition metal oxides have been extensively studied due to their large theoretical capacities, but their practical application has been hampered by low electrical conductivity and dramatic volume fluctuation during cycling. In this work, we synthesized Zn3V2O8 material using Zn-V-MOF (metal-organic framework) as a sacrificial template to improve the electrochemical characteristics of lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs). Unique dodecahedral structure, larger specific surface area and higher ability to mitigate volume changes, improve the electrochemical reaction active site while accelerating ion transport. Zn3V2O8 with 2-methylimidazole as a ligand demonstrated a discharge capacity of 1225.9 mAh/g in LIBs and 761.6 mAh/g in SIBs after 300 cycles at 0.2 C. Density functional theory (DFT) calculation illustrates the smaller diffusion barrier energy and higher specific capacity in LIBs that is ascribed to the fact that Li has a smaller size and hence its diffusion is easier. This study may lead to a path for the manufacturing of high-performance LIBs and SIBs.

2.
Front Immunol ; 14: 1339669, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38259444

RESUMO

This review in sports medicine focuses on the critical role of exosomes in managing chronic conditions and enhancing athletic performance. Exosomes, small vesicles produced by various cells, are essential for cellular communication and transporting molecules like proteins and nucleic acids. Originating from the endoplasmic reticulum, they play a vital role in modulating inflammation and tissue repair. Their significance in sports medicine is increasingly recognized, particularly in healing athletic injuries, improving articular cartilage lesions, and osteoarthritic conditions by modulating cellular behavior and aiding tissue regeneration. Investigations also highlight their potential in boosting athletic performance, especially through myocytes-derived exosomes that may enhance adaptability to physical training. Emphasizing a multidisciplinary approach, this review underlines the need to thoroughly understand exosome biology, including their pathways and classifications, to fully exploit their therapeutic potential. It outlines future directions in sports medicine, focusing on personalized treatments, clinical evaluations, and embracing technological advancements. This research represents a frontier in using exosomes to improve athletes' health and performance capabilities.


Assuntos
Cartilagem Articular , Exossomos , Medicina Esportiva , Humanos , Transporte Biológico , Comunicação Celular
3.
Phys Chem Chem Phys ; 24(48): 30027-30034, 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36472373

RESUMO

Transition-metal dichalcogenides (TMDCs) have been modified to show excellent electrocatalytic performance for the CO2 reduction reaction (CO2RR). However, little research has been reported on the edge modification of WS2 and its electrocatalytic CO2RR. In this work, the edge structure of WS2 with W atoms exposed in the top layer was established by density functional theory calculations. Through using WS2-xTM-y (x = 1, 2 or 3; y = 1 or 2; TM = Zn, Fe, Co or Ni) models by doping TM atoms on the top layer of WS2, the effects of dopant species, doping concentration and adsorption sites on their electrocatalytic activity were investigated. Among the models, the active site for the CO2RR is the W atoms. The doping of TM atoms would affect the bond strength between W and S atoms. After the doping of TM atoms in WS2-2TM-1 ones, the electrical conduction of S atoms and the underlying W atoms can greatly be improved. Thus the catalytic activities can be significantly increased, in which the WS2-2Zn-1 model shows the best catalytic activity. The limiting potential (UL) of the CO2RR to CO on the WS2-2Zn-1 model is -0.51 V and the Gibbs energy change (ΔG) for the adsorption of intermediates on the WS2-2Zn-1 model is ΔG(COOH*) = -0.37 and ΔG(CO*) = -0.51 eV, respectively. Solvation correction showed that WS2-2Zn-1 could maintain good catalytic performance in a wide range of pH values. The present results may provide a theoretical basis for the design and synthesis of novel electrocatalysts with high performance for the CO2RR.

4.
Molecules ; 27(21)2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36364009

RESUMO

The difficulty of exposing active sites and easy recombination of photogenerated carriers have always been two critical problems restricting the photocatalytic activity of g-C3N4. Herein, a simple (NH4)2MoO4-induced one-step calcination method was successfully introduced to transform bulk g-C3N4 into g-C3N4/MoO2 composites with a large specific surface area. During the calcination, with the assistance of NH3 and water vapor produced by ammonium molybdate, the pyrolytical oxidation and depolymerization of a g-C3N4 interlayer were accelerated, finally realizing the exfoliation of the g-C3N4. Furthermore, another pyrolytical product of ammonium molybdate was transformed into MoO2 under an NH3 atmosphere, which was in situ loaded on the surface of a g-C3N4 nanosheet. Additionally, the results of photocatalytic hydrogen evolution under visible light show that the optimal g-C3N4/MoO2 composite has a high specific surface area and much improved performance, which is 4.1 times that of pure bulk g-C3N4. Such performance improvement can be attributed to the full exposure of active sites and the formation of abundant heterojunctions. However, with an increasing feed amount of ammonium molybdate, the oxidation degree of g-C3N4 was enhanced, which would widen the band gap of g-C3N4, leading to a weaker response ability to visible light. The present strategy will provide a new idea for the simple realization of exfoliation and constructing a heterojunction for g-C3N4 simultaneously.

5.
J Environ Sci (China) ; 114: 204-210, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35459485

RESUMO

To investigate the effect of low-level occupational benzene exposure on human peripheral blood leukocyte counts of the workers, domestic and foreign published research data on the change of human peripheral blood leukocyte counts under low-level occupational benzene exposure from January 1990 to December 2020 were collected and analyzed. According to the literature inclusion and exclusion criteria, 18 independent studies from 12 publications were selected for meta-analysis to explore the effect of low-level occupational benzene exposure on human peripheral blood leukocyte counts. The results showed that the peripheral blood leukocyte counts abnormal rates of low-level occupational benzene exposure group were higher than those of the control group, and the difference was statistically significant. Low-level occupational benzene exposure could result in a relatively higher abnormal rate of peripheral blood leukocyte counts in the exposed population, indicating that low-level occupational benzene exposure at workplaces specified by the current benzene occupational exposure limit in China would affect the peripheral blood leukocyte counts of the workers, thus benzene with concentrations under the limit in the ambient air of workplace could be still harmful to the health of the exposed workers. The results of this study could provide a scientific basis for future revision of the benzene occupational exposure limit in China, and could also be a reference for the formulation of environmental standard concerning benzene in China in the future.


Assuntos
Benzeno , Exposição Ocupacional , Benzeno/toxicidade , China , Humanos , Contagem de Leucócitos , Exposição Ocupacional/análise
6.
Int J Gen Med ; 15: 3951-3964, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35437351

RESUMO

Background: Aortic dissection (AD) is a rare and lethal disorder with its genetic basis remains largely unknown. Many studies have confirmed that circRNAs play important roles in various physiological and pathological processes. However, the roles of circRNAs in AD are still unclear and need further investigation. The present study aimed to elucidate the underlying molecular mechanisms of circRNAs regulation in AD based on the circRNA-associated competing endogenous RNA (ceRNA) network. Methods: Expression profiles of circRNAs (GSE97745), miRNAs (GSE92427), and mRNAs (GSE52093) were downloaded from Gene Expression Omnibus (GEO) databases, and the differentially expressed RNAs (DERNAs) were subsequently identified by bioinformatics analysis. CircRNA-miRNA-mRNA ceRNA network, Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were used to predict the potential functions of circRNA-associated ceRNA network. RNA was isolated from human arterial blood samples after which qRT-PCR was performed to confirm the DERNAs. Results: We identified 14 (5 up-regulated and 9 down-regulated) differentially expressed circRNAs (DEcircRNAs), 17 (8 up-regulated and 9 down-regulated) differentially expressed miRNAs (DEmiRNAs) and 527 (297 up-regulated and 230 down-regulated) differentially expressed mRNAs (DEmRNAs) (adjusted P-value <0.05 and | log2FC | > 1.0). KEGG pathway analysis indicated that DEmRNAs were related to focal adhesion and extracellular matrix receptor interaction signaling pathways. Simultaneously, the present study constructed a ceRNA network based on 1 circRNAs (hsa_circRNA_082317), 1 miRNAs (hsa-miR-149-3p) and 10 mRNAs (MLEC, ENTPD7, SLC16A3, SLC7A8, TBC1D16, PAQR4, MAPK13, PIK3R2, ITGA5, SERPINA1). qRT-PCR demonstrated that hsa_circRNA_082317 and ITGA5 were significantly up-regulated, and hsa-miR-149-3p was dramatically down-regulated in AD (n = 3). Conclusion: This is the first study to demonstrate the circRNA-associated ceRNA network is altered in AD, implying that circRNAs may play important roles in regulating the onset and progression and thus may serve as potential biomarkers for the diagnosis and treatment of AD.

7.
Materials (Basel) ; 15(3)2022 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-35161163

RESUMO

4145H steel is a commonly used material for downhole tools. However, up to now the wear behavior of 4145H drilling tool steel under real drilling fluid environment conditions is still not clear. In this work, this was investigated using a modified ASTM B611 rubber ring wet grinding test system, in which six kinds of abrasives (talc, dolomite or fluorite, as well as their mixed abrasive with quartz) with metal hardness-to-abrasive hardness ratios (H/HA) ranging from 0.25 to 6.25 were used in the drilling fluid for experiments. The results show that the H/HA value determined the wear mechanism of 4145H steel. When a single soft abrasive was used (with H/HA higher than 1.3-1.5), polishing was the dominantly observed mechanism. While mixed abrasives were applied, a microcutting mechanism due to the ploughing of hard abrasive particles on the steel surface was also observed. The increase in mass fraction of the soft abrasives has little effect on the wear rate of 4145H steel, but its wear rate will significantly increase as the mass fraction of hard abrasives increases. Therefore, in order to extend the life of drilling tools and reduce downhole accidents, the mass fraction of hard particles in the drilling fluid should be reduced as much as possible.

8.
Sci Total Environ ; 806(Pt 1): 150283, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34563911

RESUMO

Volatile halogenated hydrocarbons (VHCs) have attracted wide attention in the atmospheric chemistry field since they not only affect the ecological environment but also damage human health. In order to better understand the characteristics, sources and health risks of VHCs in typical urban areas in Beijing, and also verify the achievement in implementing the Montreal Protocol (MP) in Beijing, observational studies on 22 atmospheric VHCs species were conducted during six air pollution episodes from December 2016 to May 2017. The range in daily mixing ratios of the 6 MP-regulated VHCs was 1000-1168 pptv, and the 16 MP-unregulated VHCs was 452-2961 pptv. The 16 MP-unregulated VHCs accounted for a relatively high concentration proportion among the 22 VHCs with a mean of 70.25%. Compared with other regions, the mixing ratios of MP-regulated VHCs were in the middle concentrations. The mixing ratios of the MP-regulated VHCs remained the same concentrations during the air pollution episodes, while the concentrations of MP-unregulated VHCs were generally higher on polluted days than on clean days and increased with the aggravation of the pollution episodes. The mixing ratios of dichlorodifluoromethane and trichlorofluoromethane were higher than Northern Hemisphere (NH) background values, while the mixing ratios of the other 4 MP-regulated VHCs were moderate and similar to the NH background values. All the 9 VHCs with carcinogenic risk might pose potential carcinogenic risks to the exposed populations in the six pollution episodes, while none of the 12 VHCs might pose appreciable non-carcinogenic risks to the exposed populations. Considering the higher concentration levels and higher risk values of 1,2-dichloropropane, 1,2-dichloroethane, carbon tetrachloride and trichloromethane, Beijing needs to further strengthen the control of these VHCs. The analysis of air mass transportation and PMF model showed that regional transportation and leakage of CFCs banks were important sources of VHCs in Beijing, and the contribution of industrial process and solvent usage should not be neglected. The results revealed the effective implementation of the MP in Beijing and its surrounding areas, while further measures are suggested to control the emissions of important VHCs especially from regional transportation and leakage of CFCs banks to reduce the possible health risks to the exposed population.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Hidrocarbonetos Halogenados , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Pequim , China , Monitoramento Ambiental , Humanos , Medição de Risco
9.
Ann Transl Med ; 9(16): 1317, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34532454

RESUMO

BACKGROUND: Colorectal cancer (CRC) is one of the most common cancers worldwide with high rates of invasiveness and mortality. DAB2IP (DOC2/DAB2 interactive protein) is a member of the RAS-GTPase-activating protein (RAS-GAP) family that shows a suppressive effect on cancer progression, is downregulated in several cancers. However, the role of DAB2IP in CRC remains elusive. METHODS: Expression of DAB2IP was evaluated in human CRC tissues using immunohistochemistry (IHC), quantitative real-time reverse transcription PCR (qRT-PCR) and immunoblotting. Knockdown and overexpression of DAB2IP in CRC cells were achieved by transfecting siRNAs and DAB2IP expression vectors and assessed by qRT-PCR and immunoblotting. CCK-8, colony formation, wound-healing, and transwell assays were used to evaluate CRC cell growth, migration, and sensitivity to chemotherapeutic drugs. The cell cycle was analyzed by propidium iodide (PI) staining and flow cytometry. Cell apoptosis was evaluated by Annexin V-DAPI double staining and flow cytometry. The effect of DAB2IP overexpression on tumor formation was explored by an in vivo tumorigenesis assay. Finally, immunoblotting was performed to examine the molecules related to the action of DAB2IP in CRC. RESULTS: Compared with para-cancer tissues, there was a marked decrease of DAB2IP expression in surgically excised CRCs. In cultured CRC cells, enforced expression of DAB2IP inhibited cell growth and migration and sensitized the cells to DNA-acting cisplatin, oxaliplatin, and doxorubicin but not 5-fluorouracil (5-FU). In contrast, knockdown of DAB2IP produced the opposite effect. Moreover, DAB2IP overexpression hindered tumor growth in vivo. We further found that DAB2IP regulated the expression of cell growth, epithelial-mesenchymal transition (EMT), and apoptosis-related proteins in CRC cells and inhibited the phosphorylation of protein kinase B (AKT) and extracellular signal-regulated kinase (ERK). CONCLUSIONS: Expression of DAB2IP inhibited CRC cell growth and migration and sensitized CRC cells to chemotherapeutic drugs. Inhibition of the phosphorylation of AKT and ERK is associated with the effects of DAB2IP expression. Restoration of DAB2IP expression may be a novel target for treating CRC.

10.
Molecules ; 26(15)2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34361672

RESUMO

A novel product consisting of a homogeneous tin oxide nanowall array with abundant oxygen deficiencies and partial Ni-Sn alloying onto a Ni foam substrate was successfully prepared using a facile solvothermal synthesis process with subsequent thermal treatment in a reductive atmosphere. Such a product could be directly used as integrated anodes for supercapacitors, which showed outstanding electrochemical properties with a maximum specific capacitance of 31.50 mAh·g-1 at 0.1 A·g-1, as well as good cycling performance, with a 1.35-fold increase in capacitance after 10,000 cycles. An asymmetric supercapacitor composed of the obtained product as the anode and activated carbon as the cathode was shown to achieve a high potential window of 1.4 V. The excellent electrochemical performance of the obtained product is mainly ascribed to the hierarchical structure provided by the integrated, vertically grown nanowall array on 3D Ni foam, the existence of oxygen deficiency and the formation of Ni-Sn alloys in the nanostructures. This work provides a general strategy for preparing other high-performance metal oxide electrodes for electrochemical applications.

11.
Adv Sci (Weinh) ; 8(16): e2101866, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34173344

RESUMO

Rechargeable potassium metal batteries are promising energy storage devices with potentially high energy density and markedly low cost. However, eliminating dendrite growth and achieving a stable electrode/electrolyte interface are the key challenges to tackle. Herein, a novel "quasi-liquid" potassium-sodium alloy (KNA) anode comprising only 3.5 wt% sodium (KNA-3.5) is reported, which exhibits outstanding electrochemical performance able to be reversibly cycled at 4 mA cm-2 for 2000 h. Moreover, it is demonstrated that adding a small amount of sodium hexafluorophosphate (NaPF6 ) into the potassium bis(fluorosulfonyl)imide electrolyte allows for the formation of the "quasi-liquid" KNA on electrode surface. Comprehensive experimental studies reveal the formation of an unusual metastable KNa2 phase during plating, which is believed to facilitate simultaneous nucleation and suppress the growth of dendrites, thereby improving the electrode's cycle lifetime. The "quasi-liquid" KNA-3.5 anode demonstrates markedly enhanced electrochemical performance in a full cell when pairing with Prussian blue analogs or sodium rhodizonate dibasic as the cathode material, compared to the pristine potassium anode. Importantly, unlike the liquid KNA reported before, the "quasi-liquid" KNA-3.5 exhibits good processability and can be readily shaped into sheet electrodes, showing substantial promise as a dendrite-free anode in rechargeable potassium metal batteries.

12.
Drug Des Devel Ther ; 14: 621-633, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32103904

RESUMO

PURPOSE: Dysfunction of endothelial cells plays a key role in the pathogenesis of diabetic atherosclerosis. High glucose (HG) has been found as a key factor in the progression of diabetic complications, including atherosclerosis. PI3K/Akt/eNOS signaling pathway has been shown to involve in HG-induced vascular injuries. Hydrogen sulfide (H2S) has been found to exhibit protective effects on HG-induced vascular injuries. Moreover, H2S activates PI3K/Akt/eNOS pathway in endothelial cells. Thus, the present study aimed to determine if H2S exerts protective effects against HG-induced injuries of human umbilical vein endothelial cells (HUVECs) via activating PI3K/Akt/eNOS signaling. MATERIALS AND METHODS: The endothelial protective effects of H2S were evaluated and compared to the controlled groups. Cell viability, cell migration and tube formation were determined by in vitro functional assays; protein levels were evaluated by Western blot assay and ELISA; cell apoptosis was determined by Hoechst 33258 nuclear staining; Reactive oxygen species (ROS) production was evaluated by the ROS detection kit. RESULTS: HG treatment significantly inhibited PI3K/Akt/eNOS signaling in HUVECs, which was partially reversed by the H2S treatment. HG treatment inhibited cell viability of HUVECs, which were markedly prevented by H2S or PI3K agonist Y-P 740. HG treatment also induced HUVEC cell apoptosis by increasing the protein levels of cleaved caspase 3, Bax and Bcl-2, which were significantly attenuated by H2S or 740 Y-P. ROS production and gp91phox protein level were increased by HG treatment in HUVECs and this effect can be blocked by the treatment with H2S or Y-P 740. Moreover, HG treatment increased the protein levels of pro-inflammatory cytokines, caspase-1 and phosphorylated JNK, which was significantly attenuated by H2S or Y-P 740. Importantly, the cytoprotective effect of H2S against HG-induced injury was inhibited by LY294002 (an inhibitor of PI3K/Akt/eNOS signaling pathway). CONCLUSION: The present study demonstrated that exogenous H2S protects endothelial cells against HG-induced injuries by activating PI3K/Akt/eNOS pathway. Based on the above findings, we proposed that reduced endogenous H2S levels and the subsequent PI3K/Akt/eNOS signaling impairment may be the important pathophysiological mechanism underlying hyperglycemia-induced vascular injuries.


Assuntos
Aterosclerose/prevenção & controle , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Sulfeto de Hidrogênio/farmacologia , Substâncias Protetoras/farmacologia , Apoptose/efeitos dos fármacos , Aterosclerose/etiologia , Sobrevivência Celular/efeitos dos fármacos , Complicações do Diabetes/prevenção & controle , Progressão da Doença , Glucose/toxicidade , Células Endoteliais da Veia Umbilical Humana/patologia , Humanos , Óxido Nítrico Sintase Tipo III/isolamento & purificação , Óxido Nítrico Sintase Tipo III/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
14.
Chem Sci ; 9(6): 1574-1585, 2018 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-29675202

RESUMO

Co-catalysis is regarded as a promising strategy to improve the hydrogen evolution performance of semiconductor-based photocatalysts. But developing a simple and effective technique to achieve the optimal synergy between co-catalysts and host photocatalysts has been a great challenge. Herein, hybrid photocatalysts consisting of ß-NiS modified CdS nanowires (NiS/CdS NWs) have been synthesized via a simple and green hydrothermal route using CdS NWs as the template from thiourea and nickel acetate in the presence of sodium hypophosphite. As a result, a metal Ni intermediate was formed via an electroless plating process assisted by H2PO2-, which facilitated the growth of highly conducting flake-like ß-NiS nanostructures onto the surface of the CdS NWs. With the optimal loading amount of NiS, the obtained NiS/CdS NWs present a record-high photocatalytic activity for H2 evolution in lactic acid aqueous solutions under visible light irradiation. At 25 °C, the rate of H2 evolution was measured as 793.6 µmol h-1 (over a 5 mg photocatalyst sample), which is nearly 250-fold higher than that over pure CdS NWs, and the apparent quantum yield reached an exceptionally high value of 74.1% at 420 nm. The mechanism for the photocatalytic H2 evolution over the present NiS/CdS NWs was also proposed. This strategy would provide new insight into the design and development of high-performance heterostructured photocatalysts.

15.
Data Brief ; 16: 828-842, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29541670

RESUMO

The data presented in this article are related to a research article entitled 'Novel ß-NiS film modified CdS nanoflowers heterostructure nanocomposite: extraordinarily highly efficient photocatalysts for hydrogen evolution' (Zhang et al., 2018) [1]. In this article, we report original data on the synthesis processes optimization of the proposed nanocomposite on the basis of their optimum photocatalytic performance together with the comparison on the results of literatures and comparative experiments. The composition, microstructure, morphology, photocatalytic hydrogen evolution and photocatalytic stability of the corresponding samples are included in this report. The data are presented in this format in order to facilitate comparison with data from other researchers in the field and understanding the mechanism of similar catalysts.

16.
Nat Commun ; 9(1): 1175, 2018 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-29563524

RESUMO

Transparent crystalline yttrium aluminum garnet (YAG; Y3Al5O12) is a dominant host material used in phosphors, scintillators, and solid state lasers. However, YAG single crystals and transparent ceramics face several technological limitations including complex, time-consuming, and costly synthetic approaches. Here we report facile elaboration of transparent YAG-based ceramics by pressureless nano-crystallization of Y2O3-Al2O3 bulk glasses. The resulting ceramics present a nanostructuration composed of YAG nanocrystals (77 wt%) separated by small Al2O3 crystalline domains (23 wt%). The hardness of these YAG-Al2O3 nanoceramics is 10% higher than that of YAG single crystals. When doped by Ce3+, the YAG-Al2O3 ceramics show a 87.5% quantum efficiency. The combination of these mechanical and optical properties, coupled with their simple, economical, and innovative preparation method, could drive the development of technologically relevant materials with potential applications in wide optical fields such as scintillators, lenses, gem stones, and phosphor converters in high-power white-light LED and laser diode.

17.
Data Brief ; 17: 842-855, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29516030

RESUMO

The data presented in this article are related to a research article entitled 'Highly efficient solar-driven photocatalytic degradation on environmental pollutants over a novel C fibers@MoSe2 nanoplates core-shell composite' (Wang et al., 2018) [1]. In this article, we report original data on the synthesis processes optimization of the proposed composite together with its formation mechanism. The report includes the composition, microstructure and morphology of the corresponding samples, and the photocatalytic activity and stability of the optimal composite. Compared with commercially available MoSe2 powder, the reaction rate constant of the optimal composite catalyst for the degradation of methylene blue (MB) and rhodamine B (RhB) under simulated sunlight irradiation (SSI) could be increased in a factor of about 14 and 8, respectively. The data are presented in this format to allow the comparison with those from other researchers in this field, and understanding the synthesis and photocatalysis mechanism of similar catalysts.

18.
J Hazard Mater ; 347: 403-411, 2018 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-29335221

RESUMO

As an important member of two-dimensional transition metal dichalcogenides, MoSe2 has a wide range of photoelectrochemical properties. However, MoSe2 alone can not directly be used as photocatalyst for its poor performance owing to the strong recombination of photogenerated electron-hole pairs. Here, we propose a novel C fibers@MoSe2 nanoplates core-shell composite, which was prepared by a facile, one-step thermal evaporation method. The composite has a remarkable feature of numerous MoSe2 thin nanoplates grown in-situ, densely and even vertically on the surface of the C fibers. Due to the effective separation of photogenerated electron-hole pairs promoted by the prompt transfer of photogenerated electrons through C fibers, compared with commercially available pure MoSe2 powder, such composite exhibits greatly improved solar-driven photocatalytic activity and high stability for the degradation of various organic/inorganic environmental pollutants including methylene blue, rhodamine B, p-chlorophenol and K2Cr2O7 aqueous solutions, showing the great potential for environmental remediation by degrading toxic industrial chemicals in waste water using sunlight. Moreover, this one-step thermal evaporation is an easy-handling, eco-friendly and low-cost synthesis method, which is suitable for large-scale production.

19.
ACS Appl Mater Interfaces ; 9(34): 28704-28715, 2017 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-28800215

RESUMO

Recently, WSe2 as a typical transition metal dichalcogenide compound has attracted extensive attention due to its potential applications in electronic and optoelectronic devices. However, WSe2 alone cannot be directly used as a photocatalyst due to its inferior performance possibly caused by the strong recombination of photogenerated electron-hole pairs. Here a novel C fibers@WSe2 nanoplates core-shell composite (NPCSC) was successfully synthesized via facile, one-step thermal evaporation, in which numerous WSe2 thin nanoplates were in situ, densely and even vertically grown on the surface of the C fibers. Such composite presents highly solar-driven photocatalytic activity and stability for the degradation of various organic aqueous dyes including methylene blue and rhodamine B, and highly harmful gases like toluene, showing the great potential for environmental remediation by degrading toxic industrial chemicals using sunlight. Under simulated sunlight irradiation, comparing with commercially available WSe2 powder, the as-synthesized C fibers@WSe2 NPCSC presents significantly enhanced reaction rate constants by a factor of approximately 15, 9, and 3 for the degradation of aqueous methylene blue, aqueous rhodamine B, and gaseous toluene, respectively, due to the effective separation of photogenerated electron-hole pairs promoted by the rapid transfer of photogenerated electrons through C fibers. Moreover, this one-step thermal evaporation is an easy-handling, environmentally friendly, and low-cost synthesis method, which is suitable for large-scale production.

20.
Nanoscale ; 9(29): 10277-10284, 2017 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-28696448

RESUMO

Novel AuAg@CdS double-walled nanotubes (DWNTs) were successfully fabricated through a three-step solvothermal method, starting with silver nanowires as the template. In the DWNTs, a uniform layer of a CdS shell is coated onto the AuAg nanotubes, finally forming the one-dimensional nanocomposites. Nonlinear optical analysis indicated that the plasmon-exciton interaction in the AuAg@CdS DWNTs induced an obviously saturated absorption response under visible light excitation, in contrast to individual AuAg nanotubes and CdS shells. Furthermore, the effective nonlinear absorption coefficient of the AuAg@CdS DWNTs was 7 times larger than that of the CdS shell, which was attributed to the local field enhancement effect. Such a unique morphological configuration and optical properties make AuAg@CdS DWNTs an ideal candidate for next generation nano-photonic devices employed as a mode-locking element, optical switch, and so on.

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