The biggest challenging issue in photocatalysis is efficient separation of the photoinduced carriers and the aggregation of photoexcited electrons on photocatalyst’s surface.In this paper,we report that double metall...The biggest challenging issue in photocatalysis is efficient separation of the photoinduced carriers and the aggregation of photoexcited electrons on photocatalyst’s surface.In this paper,we report that double metallic co-catalysts Ti3C2 MXene and metallic octahedral(1T)phase tungsten disulfide(WS2)act pathways transferring photoexcited electrons in assisting the photocatalytic H2 evolution.TiO2 nanosheets were in situ grown on highly conductive Ti3C2 MXenes and 1T-WS2 nanoparticles were then uniformly distributed on TiO2@Ti3C2 composite.Thus,a distinctive 1T-WS2@TiO2@Ti3C2 composite with double metallic co-catalysts was achieved,and the content of 1T phase reaches 73%.The photocatalytic H2 evolution performance of 1T-WS2@TiO2@Ti3C2 composite with an optimized 15 wt%WS2 ratio is nearly 50 times higher than that of TiO2 nanosheets because of conductive Ti3C2 MXene and 1T-WS2 resulting in the increase of electron transfer efficiency.Besides,the 1T-WS2 on the surface of TiO2@Ti3C2 composite enhances the Brunauer–Emmett–Teller surface area and boosts the density of active site.展开更多
WS2 nanosheets were prepared by the solvent-thermal method in the presence of n-butyl lithium, then the exfoliation under the condition of ultrasound. The formed WS2 nanosheets were conjugated with thiol-modified poly...WS2 nanosheets were prepared by the solvent-thermal method in the presence of n-butyl lithium, then the exfoliation under the condition of ultrasound. The formed WS2 nanosheets were conjugated with thiol-modified polyethylene glycol （PEG-SH） to improve the biocompatibility. The nanosheets （WS2- PEG） were able to inhibit the growth of a model HeLa cancer cell line in vitro due to the high photothermal conversion efficiency of ~35% irradiated by an 808 nm laser （1 W/cm^2）. As a proof of concept, WS2-PEG nanosheets with the better X-ray attenuation property than the clinical computed tomography （CT） contrast agent （lohexol） could be performed for CT imaging of the lymph vessel.展开更多
WS2 nanomaterials have attracted great attention in the field of electromagnetic wave absorption due to their high specific surface area,layered structure,and peculiar electronic properties.However,further improvement...WS2 nanomaterials have attracted great attention in the field of electromagnetic wave absorption due to their high specific surface area,layered structure,and peculiar electronic properties.However,further improvements on their limited electromagnetic absorbing(EMA)capacity and bandwidth are urgently required for their practical application as EMA absorbents.In this work,WS2/NiO hybrids with heterostructures are prepared by a hydrothermal method and developed into EMA absorbents.The maximum reflection loss of the hybrids with 20%NiO loading could reach-53.31 dB at a thickness of 4.30 mm;the bandwidth with a reflection loss value of less than-10 dB is determined to be13.46 GHz(4.54–18 GHz)when the thickness of the absorbent is between 3.5 and 5.5 mm.It is found that the enhanced EMA performance of WS2/NiO hybrids is caused by the addition of magnetic NiO,which could result in the interfaces between WS2 and NiO being responsible for the synergetic magnetic loss and dielectric loss in the hybrids.This work provides a new approach for the design of excellent EMA materials for practical applications.展开更多
In this paper,the determination of Thiram fungicide by a novel modified screen-printed carbon electrode(SPCE)fabricated modifying the working electrode(WE)with 2D-GO/WS2nanohybrid composites,is reported.Scanning elect...In this paper,the determination of Thiram fungicide by a novel modified screen-printed carbon electrode(SPCE)fabricated modifying the working electrode(WE)with 2D-GO/WS2nanohybrid composites,is reported.Scanning electron microscopy(SEM),Raman spectroscopy,and fluorescence analysis(PL)were used to reveal the morphological and microstructural characteristics of the 2D-GO/WS2 nanohybrids with different graphene oxide:tungsten disulphide(GO:WS_(2))ratio.Electrochemical characterization demonstrated that the 2D-WS2/GO nanohybrids having a GO:WS_(2)ratio=2:1 shows the highest electrocatalytic activity towards oxidation of Thiram.The developed sensor permits the quantification of Thiram in the linear range 0.083-0.33μM with a limit of detection(LOD)of 0.02μM,which is below the legal limits for this fungicide in drinking water or foods.展开更多
Photoreduction of hexavalent uranium(U(VI))by semiconductor provides a novel and effective avenue for uranium extraction.Unfortunately,the traditional metal oxide and sulfide semiconductors suffer from the lack of con...Photoreduction of hexavalent uranium(U(VI))by semiconductor provides a novel and effective avenue for uranium extraction.Unfortunately,the traditional metal oxide and sulfide semiconductors suffer from the lack of confinement sites to U(VI),which resulted in the long period(~1 h)to achieve a high U(VI)extraction efficiency of>90%.Herein,we successfully constructed WS2 nanosheets and created in-situ oxidized domains on the surfaces(O-WS_(2))to promote the uranium extraction and the corresponding removal kinetics.In this system,the O_(7.7-)WS_(2) nanosheets exhibited a considerable U(VI)extraction efficiency of>90%within 20 min in 8 mg·L^(–1) U(VI)-containing solution,which represented the highly efficient U(VI)removal performance.In 200 mg·L^(–1) U(VI)-containing solution,the O7.7-WS2 nanosheets exhibited an extraction capacity of 652.4 mg·g^(-1).The mechanism study revealed that the oxidized surface tended to trap hydrogen atom and in-situ form hydroxyl groups in defect sites.Evidenced by a series of experiment,such as kinetic isotope effect,1H nuclear magnetic resonance(NMR)spectra,and X-ray absorption near-edge structure(XANES)spectra,the in-situ formed hydroxyl groups participated in the uranium reduction,which dramatically enhanced uranium extraction kinetics and efficiency.展开更多
基金fundings from the National Natural Science Foundation of China (Nos. 51872173 and 51772167)Taishan Scholarship of Young Scholars (No. tsqn201812068)+2 种基金Natural Science Foundation of Shandong Province (No. ZR2017JL020)Taishan Scholarship of Climbing Plan (No. tspd20161006)Key Research and Development Program of Shandong Province (No. 2018GGX102028)
文摘The biggest challenging issue in photocatalysis is efficient separation of the photoinduced carriers and the aggregation of photoexcited electrons on photocatalyst’s surface.In this paper,we report that double metallic co-catalysts Ti3C2 MXene and metallic octahedral(1T)phase tungsten disulfide(WS2)act pathways transferring photoexcited electrons in assisting the photocatalytic H2 evolution.TiO2 nanosheets were in situ grown on highly conductive Ti3C2 MXenes and 1T-WS2 nanoparticles were then uniformly distributed on TiO2@Ti3C2 composite.Thus,a distinctive 1T-WS2@TiO2@Ti3C2 composite with double metallic co-catalysts was achieved,and the content of 1T phase reaches 73%.The photocatalytic H2 evolution performance of 1T-WS2@TiO2@Ti3C2 composite with an optimized 15 wt%WS2 ratio is nearly 50 times higher than that of TiO2 nanosheets because of conductive Ti3C2 MXene and 1T-WS2 resulting in the increase of electron transfer efficiency.Besides,the 1T-WS2 on the surface of TiO2@Ti3C2 composite enhances the Brunauer–Emmett–Teller surface area and boosts the density of active site.
基金partially supported by National Natural Science Foundation of China (Nos.21271130,21371122,and 11275050)Program for Changjiang Scholars and Innovative Research Team in University (No.IRT1269)+4 种基金Shanghai Science and Technology Development Fund (Nos.12ZR1421800 and 13520502800)Shanghai Pujiang Program (No.13PJ1406600)Shanghai Municipal Education Commission (No.13ZZ110)Shanghai Normal University (Nos.DXL122 and SK201339)International Joint Laboratory on Resource Chemistry (IJLRC)
文摘WS2 nanosheets were prepared by the solvent-thermal method in the presence of n-butyl lithium, then the exfoliation under the condition of ultrasound. The formed WS2 nanosheets were conjugated with thiol-modified polyethylene glycol （PEG-SH） to improve the biocompatibility. The nanosheets （WS2- PEG） were able to inhibit the growth of a model HeLa cancer cell line in vitro due to the high photothermal conversion efficiency of ~35% irradiated by an 808 nm laser （1 W/cm^2）. As a proof of concept, WS2-PEG nanosheets with the better X-ray attenuation property than the clinical computed tomography （CT） contrast agent （lohexol） could be performed for CT imaging of the lymph vessel.
基金supported by the National Natural Science Foundation of China(51272110,51772160,and 51977009).
文摘WS2 nanomaterials have attracted great attention in the field of electromagnetic wave absorption due to their high specific surface area,layered structure,and peculiar electronic properties.However,further improvements on their limited electromagnetic absorbing(EMA)capacity and bandwidth are urgently required for their practical application as EMA absorbents.In this work,WS2/NiO hybrids with heterostructures are prepared by a hydrothermal method and developed into EMA absorbents.The maximum reflection loss of the hybrids with 20%NiO loading could reach-53.31 dB at a thickness of 4.30 mm;the bandwidth with a reflection loss value of less than-10 dB is determined to be13.46 GHz(4.54–18 GHz)when the thickness of the absorbent is between 3.5 and 5.5 mm.It is found that the enhanced EMA performance of WS2/NiO hybrids is caused by the addition of magnetic NiO,which could result in the interfaces between WS2 and NiO being responsible for the synergetic magnetic loss and dielectric loss in the hybrids.This work provides a new approach for the design of excellent EMA materials for practical applications.
基金supported by the European Union (Next Generation EU)through the MUR-PNRR project SAMOTHRACE (No.ECS00000022)。
文摘In this paper,the determination of Thiram fungicide by a novel modified screen-printed carbon electrode(SPCE)fabricated modifying the working electrode(WE)with 2D-GO/WS2nanohybrid composites,is reported.Scanning electron microscopy(SEM),Raman spectroscopy,and fluorescence analysis(PL)were used to reveal the morphological and microstructural characteristics of the 2D-GO/WS2 nanohybrids with different graphene oxide:tungsten disulphide(GO:WS_(2))ratio.Electrochemical characterization demonstrated that the 2D-WS2/GO nanohybrids having a GO:WS_(2)ratio=2:1 shows the highest electrocatalytic activity towards oxidation of Thiram.The developed sensor permits the quantification of Thiram in the linear range 0.083-0.33μM with a limit of detection(LOD)of 0.02μM,which is below the legal limits for this fungicide in drinking water or foods.
基金supported by the National Natural Science Foundation of China(NSFC)(Nos.21902130,21906154,and 21976147)Sichuan Science and Technology Program(Nos.2022YFG0371,2020JDJQ0060,and 2020JDRC0089)Natural Science Foundation of Anhui province(No.2008085QB81)。
文摘Photoreduction of hexavalent uranium(U(VI))by semiconductor provides a novel and effective avenue for uranium extraction.Unfortunately,the traditional metal oxide and sulfide semiconductors suffer from the lack of confinement sites to U(VI),which resulted in the long period(~1 h)to achieve a high U(VI)extraction efficiency of>90%.Herein,we successfully constructed WS2 nanosheets and created in-situ oxidized domains on the surfaces(O-WS_(2))to promote the uranium extraction and the corresponding removal kinetics.In this system,the O_(7.7-)WS_(2) nanosheets exhibited a considerable U(VI)extraction efficiency of>90%within 20 min in 8 mg·L^(–1) U(VI)-containing solution,which represented the highly efficient U(VI)removal performance.In 200 mg·L^(–1) U(VI)-containing solution,the O7.7-WS2 nanosheets exhibited an extraction capacity of 652.4 mg·g^(-1).The mechanism study revealed that the oxidized surface tended to trap hydrogen atom and in-situ form hydroxyl groups in defect sites.Evidenced by a series of experiment,such as kinetic isotope effect,1H nuclear magnetic resonance(NMR)spectra,and X-ray absorption near-edge structure(XANES)spectra,the in-situ formed hydroxyl groups participated in the uranium reduction,which dramatically enhanced uranium extraction kinetics and efficiency.
