Polymeric nanocomposites of PS/PMMA/CdS and PS/PVC/CdS samples have been synthesized through dispersion solution casting technique. The nanoparrticles of CdS were prepared by simple chemical method using CdCl2 and H2S...Polymeric nanocomposites of PS/PMMA/CdS and PS/PVC/CdS samples have been synthesized through dispersion solution casting technique. The nanoparrticles of CdS were prepared by simple chemical method using CdCl2 and H2S gas produced from thiourea. The nanoscale morphology of the prepared polymeric nanocomposite samples is probed through small angle X-ray scattering (SAXS). The SAXS study reveals that CdS nanoparticles take place at voids position in the respective plymer blend matrix and exhibit their nano nature with very little tendency to agglomerates.展开更多
A systematic investigation of the microstructure of CrAlCxN1-x coatings as a function of carbon contents was conducted. Quaternary CrAlCxN1-x coatings were deposited on Si wafers by a hybrid coating system combining a...A systematic investigation of the microstructure of CrAlCxN1-x coatings as a function of carbon contents was conducted. Quaternary CrAlCxN1-x coatings were deposited on Si wafers by a hybrid coating system combining an arc-ion plating technique and a DC reactive magnetron sputtering technique using Cr and Al targets in the Ar/N2/CH4 gaseous mixture. The effect of carbon content on microstructure of CrAlCxN1-x coatings was investigated with instrumental analyses of X-ray diffraction, X-ray photoelectron, and high-resolution transmission electron microscopy. The results show that the carbon content of CrAlCxN1-x coatings linearly increases with increasing CH4/(CH4/N2) gas flow rate ratio. The surface roughness of the CrAlCxN1-x coating layer decreases with the increase of carbon content.展开更多
Polyamide I1 （PAll） and its nanocomposites with different organoclay loadings were prepared by melt-compounding and subsequent pelletizing. The crystal phase transitions of PAl 1 and its clay nanocomposites were inv...Polyamide I1 （PAll） and its nanocomposites with different organoclay loadings were prepared by melt-compounding and subsequent pelletizing. The crystal phase transitions of PAl 1 and its clay nanocomposites were investigated by variable-temperature X-ray diffraction. It was found that the Brill transition of the nanocomposite was 20 K higher than that of the neat PAl 1 for both heating and cooling processes. The PAl 1 d-spacings of the nanocomposites were observed to be smaller than those of the neat PAl 1 for melt crystallization. The constraints imposed by the addition of layered clay, restricting the thermal expansion of the polymer chains, are probably responsible for such a reduction of the d-spacing.展开更多
Formaldehyde is a common atmospheric pollutant produced in industrial production and daily life.However,the traditional semiconductor formaldehyde gas sensor cannot work at room temperature,which limits its practical ...Formaldehyde is a common atmospheric pollutant produced in industrial production and daily life.However,the traditional semiconductor formaldehyde gas sensor cannot work at room temperature,which limits its practical application.Therefore,developing high-performance gas sensors for rapidly and accurately detecting formaldehyde at room temperature is an important topic.In this study,Ti_(3)C_(2)Tx/SnO_(2)heterostructures were constructed,which could selectively detect formaldehyde at room temperature with a response value of 29.16%(10×10^(-6)).In addition,the sensor shows a remarkable theoretical detection limit of 5.09×10^(-9)and good longterm stability.Density functional theory(DFT)simulations reveal that SnO_(2)nano spheres provide the majority of adsorption sites that strongly interact with formaldehyde.Meanwhile,Ti_(3)C_(2)T_(x)acting as a conductive layer facilitates the transfer of charge carriers so that they show a sensing response to formaldehyde at room temperature.Moreover,the formation of p-n heterostructures between SnO_(2)and Ti_(3)C_(2)T_(x)boosts the Schottky barrier at the interface,which is the critical factor in enhancing the sensing properties by turning the Schottky barrier upon introducing formaldehyde gas.This perspective is expected to provide instructive guidance for utilizing MXene/metal oxide nanocomposites to improve the gas sensing performance at room temperature.展开更多
文摘Polymeric nanocomposites of PS/PMMA/CdS and PS/PVC/CdS samples have been synthesized through dispersion solution casting technique. The nanoparrticles of CdS were prepared by simple chemical method using CdCl2 and H2S gas produced from thiourea. The nanoscale morphology of the prepared polymeric nanocomposite samples is probed through small angle X-ray scattering (SAXS). The SAXS study reveals that CdS nanoparticles take place at voids position in the respective plymer blend matrix and exhibit their nano nature with very little tendency to agglomerates.
基金Project supported by a grant from the Fundamental R&D Program for Core Technology of Materials funded by the Ministry of Knowledge Economy, KoreaProject (2010-0001-226) supported by NCRC(National Core Research Center) Program through the National Research Foundation of Korea funded by the Ministry of Education, Science and Technology
文摘A systematic investigation of the microstructure of CrAlCxN1-x coatings as a function of carbon contents was conducted. Quaternary CrAlCxN1-x coatings were deposited on Si wafers by a hybrid coating system combining an arc-ion plating technique and a DC reactive magnetron sputtering technique using Cr and Al targets in the Ar/N2/CH4 gaseous mixture. The effect of carbon content on microstructure of CrAlCxN1-x coatings was investigated with instrumental analyses of X-ray diffraction, X-ray photoelectron, and high-resolution transmission electron microscopy. The results show that the carbon content of CrAlCxN1-x coatings linearly increases with increasing CH4/(CH4/N2) gas flow rate ratio. The surface roughness of the CrAlCxN1-x coating layer decreases with the increase of carbon content.
基金financially supported by the National Natural Science Foundation of China(No.51125011)Guangxi Small Highland Innovation Team of Talents in Colleges and UniversitiesGuangxi Funds for Specially-appointed Expert
文摘Polyamide I1 （PAll） and its nanocomposites with different organoclay loadings were prepared by melt-compounding and subsequent pelletizing. The crystal phase transitions of PAl 1 and its clay nanocomposites were investigated by variable-temperature X-ray diffraction. It was found that the Brill transition of the nanocomposite was 20 K higher than that of the neat PAl 1 for both heating and cooling processes. The PAl 1 d-spacings of the nanocomposites were observed to be smaller than those of the neat PAl 1 for melt crystallization. The constraints imposed by the addition of layered clay, restricting the thermal expansion of the polymer chains, are probably responsible for such a reduction of the d-spacing.
基金financially supported by the National Natural Science Foundation of China(No.61973223)the Innovative Talents in Colleges and Universities in Liaoning Province(No.2020389)+3 种基金Liao Ning Revitalization Talents Program(No.XLYC2007051)Liaoning Educational Department Foundation(No.LJKMZ20220762)the Natural Science Foundation of Liaoning Province(No.2021-MS-257)the Young and Middle-aged Scientific and Technological Innovation Talents of Shenyang Science and Technology Bureau(No.RC200352)。
文摘Formaldehyde is a common atmospheric pollutant produced in industrial production and daily life.However,the traditional semiconductor formaldehyde gas sensor cannot work at room temperature,which limits its practical application.Therefore,developing high-performance gas sensors for rapidly and accurately detecting formaldehyde at room temperature is an important topic.In this study,Ti_(3)C_(2)Tx/SnO_(2)heterostructures were constructed,which could selectively detect formaldehyde at room temperature with a response value of 29.16%(10×10^(-6)).In addition,the sensor shows a remarkable theoretical detection limit of 5.09×10^(-9)and good longterm stability.Density functional theory(DFT)simulations reveal that SnO_(2)nano spheres provide the majority of adsorption sites that strongly interact with formaldehyde.Meanwhile,Ti_(3)C_(2)T_(x)acting as a conductive layer facilitates the transfer of charge carriers so that they show a sensing response to formaldehyde at room temperature.Moreover,the formation of p-n heterostructures between SnO_(2)and Ti_(3)C_(2)T_(x)boosts the Schottky barrier at the interface,which is the critical factor in enhancing the sensing properties by turning the Schottky barrier upon introducing formaldehyde gas.This perspective is expected to provide instructive guidance for utilizing MXene/metal oxide nanocomposites to improve the gas sensing performance at room temperature.
