Cap-like α-Fe2O3 films are fabricated and deposited onto quartz fabric by using radio frequency magnetron sputtering and annealing.The treated fabric sample in this study shows highly sensitive surface-enhanced Raman...Cap-like α-Fe2O3 films are fabricated and deposited onto quartz fabric by using radio frequency magnetron sputtering and annealing.The treated fabric sample in this study shows highly sensitive surface-enhanced Raman scattering (SERS) and excellent flexibility,reproducibility and stability.In addition,the sample can be recovered after a washing process with an organic solvent and repeatedly used.The sensitive SERS performance is attributed to chemical enhancement through a charge transfer process.Moreover,the SERS performance is also found to be dependent on the light coupling effect.When the light absorbance rate of the α-Fe2O3 films increases at a wavelength near that of laser light,the film shows excellent sensitivity due to light coupling effect.展开更多
The environmental repercussions of wastewater from the dye process mean that it is very important to obtain an eco-friendly photocatalyst that would degrade wastewater.Herein,bismuth tungstate/graphene oxide(Bi_(2)WO_...The environmental repercussions of wastewater from the dye process mean that it is very important to obtain an eco-friendly photocatalyst that would degrade wastewater.Herein,bismuth tungstate/graphene oxide(Bi_(2)WO_(6)/GO)composites are fabricated through in-situ hydrothermal reaction and then the Bi_(2)WO_(6)/GO photocatalysts are deposited onto polyethylene terephthalate(PET)fabric.The obtained Bi_(2)WO_(6)/GO deposited PET fabrics are then characterized through XPS,Raman,SEM,TEM,XRD,UV-vis,BET method and photoluminescence spectroscopy(PL)to investigate their chemical and crystal structures,morphology,optical property,surface area and photochemical properties.Photocatalytic performance is studied through examining the rate of degrading rhodamine B(RhB)under visible light.Surface of PET fibers is densely covered with Bi_(2)WO_(6)/GO.Bi_(2)WO_(6)/GO deposited PET fabrics show a broad absorption band in the visible spectra.Removal rate of RhB on the Bi_(2)WO_(6)/GO deposited PET fabric is the highest with the GO content of 2 g/L(labeled as Bi_(2)WO_(6)/2 g/LGO).The result of active species experiment shows that superoxide radicals(·O_(2)^(−))plays a major role in the degradation of RhB.Moreover,Bi_(2)WO_(6)/2 g/LGO deposited PET fabric shows excellent cycle stability of photocatalytic degradation for RhB.The findings in this work can be extended to preparation other types of composite on the textile for photocatalysis,which can be applied to remove dyes in the wastewater produced by the textile or leather industry.展开更多
The problems of electromagnetic wave(EMW)pollution in X and Ku bands(8–18 GHz)are becoming more and more serious.Therefore,it is urgent to design EMW absorbing materials with high-efficiency such as thin thickness,li...The problems of electromagnetic wave(EMW)pollution in X and Ku bands(8–18 GHz)are becoming more and more serious.Therefore,it is urgent to design EMW absorbing materials with high-efficiency such as thin thickness,lightweight,wide bandwidth and strong EMW absorption.Inspired by the biomorph of sea cucumber,Nb_(2)CT_(x) MXene@Co nitrogen-doped carbon nanosheet arrays@carbon fiber aerogels(Nb_(2)CT_(x)@Co-NC@CFA,Nb_(2)CT_(x)=niobium carbide)were constructed by self-assembly,in-situ chemical deposition and subsequent pyrolysis.The carbon fiber aerogel,as the basic skeleton of sea cucumber,forms lightweight three-dimensional interconnected conductive network,enhances the dielectric loss and extends the multiple reflection and absorption paths of EMW.As the tentacles of sea cucumber surface,Nb_(2)CT_(x) MXene and Co nitrogen-doped carbon nanosheet arrays exist rich heterogeneous interfaces,which play an important role in improving EMW polarization loss and optimizing impedance matching.The minimum reflection loss(RLmin)of Nb_(2)CT_(x)@Co-NC@CFA reaches−54.7 dB at 9.84 GHz(2.36 mm)with a low filling ratio of 10 wt.%and the effective absorption bandwidth(EAB)of Nb_(2)CT_(x)@Co-NC@CFA reaches 2.96 GHz(8.48–11.44 GHz)with 2.36 mm and 5.2 GHz(12.8–18 GHz)with 1.6 mm,covering most of X and Ku bands by adjusting thickness.The radar cross section(RCS)value of Nb_(2)CT_(x)@Co-NC@CFA is 26.64 dB·m^(2),which is lower than that of the perfect electrical conductor(PEC),indicating that Nb_(2)CT_(x)@Co-NC@CFA can effectively decrease the probability of the target being detected by the radar detector.This work provides ideas for design and development of EMW absorbing materials with high-efficiency EMW absorption in X and Ku bands.展开更多
Abstract Biodegradable poly（ether-imide-ester） elasto- mers were synthesized from succinic acid, 1,4-butanediol, polyethylene glycol 1000 and N＇,N-bis（2-carboxyethyl）- pyromellitimide which was derived from pyrom...Abstract Biodegradable poly（ether-imide-ester） elasto- mers were synthesized from succinic acid, 1,4-butanediol, polyethylene glycol 1000 and N＇,N-bis（2-carboxyethyl）- pyromellitimide which was derived from pyromellitic dianhydride and glycine. The chemical structures, crystal- linities, thermal stabilities, mechanical properties, hydro- philicities and biodegradabilities of these elastomers were investigated. The hard segments of the linear aliphatic poly （ether-ester） exhibited monoclinic chain packing. Increas- ing the amount of aromatic bisimide moieties in the poly （ether-ester） reduced the crystallinity of the material and improved the thermal stability and tensile strength of the elastomers. In addition, introducing a suitable amount of aromatic bisimide moieties into the poly（ether-ester） backbones endowed the elastomers with improved biode- gradability but too many aromatic bisimide groups reduced the biodegradability of the elastomers.展开更多
文摘Cap-like α-Fe2O3 films are fabricated and deposited onto quartz fabric by using radio frequency magnetron sputtering and annealing.The treated fabric sample in this study shows highly sensitive surface-enhanced Raman scattering (SERS) and excellent flexibility,reproducibility and stability.In addition,the sample can be recovered after a washing process with an organic solvent and repeatedly used.The sensitive SERS performance is attributed to chemical enhancement through a charge transfer process.Moreover,the SERS performance is also found to be dependent on the light coupling effect.When the light absorbance rate of the α-Fe2O3 films increases at a wavelength near that of laser light,the film shows excellent sensitivity due to light coupling effect.
基金Joint Fund of the National Natural Science Foundation of China(No.U1833118)Sichuan Science and Technology Program(2019YFG0244).
文摘The environmental repercussions of wastewater from the dye process mean that it is very important to obtain an eco-friendly photocatalyst that would degrade wastewater.Herein,bismuth tungstate/graphene oxide(Bi_(2)WO_(6)/GO)composites are fabricated through in-situ hydrothermal reaction and then the Bi_(2)WO_(6)/GO photocatalysts are deposited onto polyethylene terephthalate(PET)fabric.The obtained Bi_(2)WO_(6)/GO deposited PET fabrics are then characterized through XPS,Raman,SEM,TEM,XRD,UV-vis,BET method and photoluminescence spectroscopy(PL)to investigate their chemical and crystal structures,morphology,optical property,surface area and photochemical properties.Photocatalytic performance is studied through examining the rate of degrading rhodamine B(RhB)under visible light.Surface of PET fibers is densely covered with Bi_(2)WO_(6)/GO.Bi_(2)WO_(6)/GO deposited PET fabrics show a broad absorption band in the visible spectra.Removal rate of RhB on the Bi_(2)WO_(6)/GO deposited PET fabric is the highest with the GO content of 2 g/L(labeled as Bi_(2)WO_(6)/2 g/LGO).The result of active species experiment shows that superoxide radicals(·O_(2)^(−))plays a major role in the degradation of RhB.Moreover,Bi_(2)WO_(6)/2 g/LGO deposited PET fabric shows excellent cycle stability of photocatalytic degradation for RhB.The findings in this work can be extended to preparation other types of composite on the textile for photocatalysis,which can be applied to remove dyes in the wastewater produced by the textile or leather industry.
基金financially supported by the National Natural Science Foundation of China and the Civil Aviation Administration of China(No.U1833118)the Open Project Program of High-Tech Organic Fibers Key Laboratory of Sichuan Province(No.PLN2022-10)+3 种基金the Science and Technology Plan Project of Chengdu City(2022-YF05-00411-SN)Science and Technology Planning Project of Sichuan Province(Nos.2023YFQ0090,2024YFHZ0218,2023YFN0016,and 2023YFQ083)Yibin Science and Technology Plan Project(No.2022JB013)Engineering characteristic team of Sichuan University(No.2020SCUNG122).
文摘The problems of electromagnetic wave(EMW)pollution in X and Ku bands(8–18 GHz)are becoming more and more serious.Therefore,it is urgent to design EMW absorbing materials with high-efficiency such as thin thickness,lightweight,wide bandwidth and strong EMW absorption.Inspired by the biomorph of sea cucumber,Nb_(2)CT_(x) MXene@Co nitrogen-doped carbon nanosheet arrays@carbon fiber aerogels(Nb_(2)CT_(x)@Co-NC@CFA,Nb_(2)CT_(x)=niobium carbide)were constructed by self-assembly,in-situ chemical deposition and subsequent pyrolysis.The carbon fiber aerogel,as the basic skeleton of sea cucumber,forms lightweight three-dimensional interconnected conductive network,enhances the dielectric loss and extends the multiple reflection and absorption paths of EMW.As the tentacles of sea cucumber surface,Nb_(2)CT_(x) MXene and Co nitrogen-doped carbon nanosheet arrays exist rich heterogeneous interfaces,which play an important role in improving EMW polarization loss and optimizing impedance matching.The minimum reflection loss(RLmin)of Nb_(2)CT_(x)@Co-NC@CFA reaches−54.7 dB at 9.84 GHz(2.36 mm)with a low filling ratio of 10 wt.%and the effective absorption bandwidth(EAB)of Nb_(2)CT_(x)@Co-NC@CFA reaches 2.96 GHz(8.48–11.44 GHz)with 2.36 mm and 5.2 GHz(12.8–18 GHz)with 1.6 mm,covering most of X and Ku bands by adjusting thickness.The radar cross section(RCS)value of Nb_(2)CT_(x)@Co-NC@CFA is 26.64 dB·m^(2),which is lower than that of the perfect electrical conductor(PEC),indicating that Nb_(2)CT_(x)@Co-NC@CFA can effectively decrease the probability of the target being detected by the radar detector.This work provides ideas for design and development of EMW absorbing materials with high-efficiency EMW absorption in X and Ku bands.
文摘Abstract Biodegradable poly（ether-imide-ester） elasto- mers were synthesized from succinic acid, 1,4-butanediol, polyethylene glycol 1000 and N＇,N-bis（2-carboxyethyl）- pyromellitimide which was derived from pyromellitic dianhydride and glycine. The chemical structures, crystal- linities, thermal stabilities, mechanical properties, hydro- philicities and biodegradabilities of these elastomers were investigated. The hard segments of the linear aliphatic poly （ether-ester） exhibited monoclinic chain packing. Increas- ing the amount of aromatic bisimide moieties in the poly （ether-ester） reduced the crystallinity of the material and improved the thermal stability and tensile strength of the elastomers. In addition, introducing a suitable amount of aromatic bisimide moieties into the poly（ether-ester） backbones endowed the elastomers with improved biode- gradability but too many aromatic bisimide groups reduced the biodegradability of the elastomers.
