Low-dimensional Bi2Fe4O9 nanosheets and microrods have been selectively prepared by a solvothermal method, from which the growth of the Bi2Fe4O9 crystals can be controlled by the variation of reaction conditions. Stru...Low-dimensional Bi2Fe4O9 nanosheets and microrods have been selectively prepared by a solvothermal method, from which the growth of the Bi2Fe4O9 crystals can be controlled by the variation of reaction conditions. Structure determination showed that the nanosheets are mainly exposed by {001} facets while the microrods are exposed by {110} facets. Ab- sorption spectra revealed that there are two bandgaps observed for both nanosheets （at 1.9 and 1.55 eV） and microrods （1.7 and 1.45 eV）, and they both would be available for the sunlight photocatalysis e ciently due to the intensive absorption ability in a wide region. Photocatalytic investigation demonstrated that the overall photocatalytic performance of the microrods is prior to that of the nanosheets due to the variation of bandgaps and exposed facets. The present report provides a useful alternative strategy for the controlling growth of nanostructures and/or microcrystals besides the present demonstration of the Bi2Fe4O9 crystals with diflerent bandgaps and facets that would be able to tune the corresponding photocatalytic ability selectively.展开更多
The γ＇-Fe4N films on Cu underlayers are deposited on the glass and Si substrates by dc magnetron reactive sputtering. The effects of Cu underlayer on the structure, morphology and magnetic properties of the γ＇-Fe4...The γ＇-Fe4N films on Cu underlayers are deposited on the glass and Si substrates by dc magnetron reactive sputtering. The effects of Cu underlayer on the structure, morphology and magnetic properties of the γ＇-Fe4N films are studied. The single-phase γ＇-Fe4N films with Cu underlayers on the glass substrate are obtained, while the mixture of Fe and γ＇-Fe4N is observed on the Si substrate. In comparison with the films without Cu underlayers, the grains of the films with Cu underlayers exhibit a non-uniform size distribution and give rise to a rougher surface. The magnetic measurements indicate that the γ＇-Fe4N films show a good soft ferromagnetic behavior. The enhanced coercivity in the films with Cu underlayers is observed due to the deterioration of the crystallographic structure as well as the rougher surface.展开更多
Low-temperature specific heat(SH)is measured for the 12442-type KCa2Fe4As4F2 single crystal under different magnetic fields.A clear SH jump with the height of?C/T|Tc=130 mJ mol-1 K-2 is observed at the superconducting...Low-temperature specific heat(SH)is measured for the 12442-type KCa2Fe4As4F2 single crystal under different magnetic fields.A clear SH jump with the height of?C/T|Tc=130 mJ mol-1 K-2 is observed at the superconducting transition temperature Tc.It is found that the electronic SH coefficient?γ(H)quickly increases when the field is in the low-field region below 3T and then considerably slows down the increase with a further increase in the field,which indicates a rather strong anisotropy or multi-gap feature with a small minimum in the superconducting gap(s).The temperature-dependent SH data indicate the presence of the T2 term,which supplies further information and supports the picture with a line-nodal gap structure.Moreover,the onset point of the SH transition remains almost unchanged under the field as high as 9 T,which is similar to that observed in cuprates,and places this system in the middle between the BCS limit and the Bose-Einstein condensation.展开更多
Ferromagnetic Fe3O4 nanoparticles were synthesized using water as the solvent through the sol-gel method, which was selected for its cost-effectiveness, simplicity, and eco-friendly nature. The synthesized nanoparticl...Ferromagnetic Fe3O4 nanoparticles were synthesized using water as the solvent through the sol-gel method, which was selected for its cost-effectiveness, simplicity, and eco-friendly nature. The synthesized nanoparticles were characterized using a variety of techniques, including Fourier Transform Infrared (FTIR) spectroscopy, X-ray powder diffraction (XRD), Scanning Electron Microscopy (SEM), Thermogravimetric Analysis (TGA), and Vibrating Sample Magnetometer (VSM). These characterizations confirmed the successful formation of Fe3O4 nanoparticles. The FTIR spectra identified characteristic peaks corresponding to the functional groups present, and XRD analysis, using Scherer’s equation, determined an average crystalline size of 1.2 nm for the Fe3O4 nanoparticles. TGA results demonstrated the thermal stability of the nanoparticles, SEM imaging revealed distinct honeycomb-like structures for the nanoparticles synthesized with water as the solvent, while the VSM analysis was used to determine the magnetic behavior of the nanoparticles.展开更多
Herein,binary and ternary MOF/carbon based composites(MOF/Carbon nitride/Graphene oxide)(novel binary(NH_(2)-MIL-88B(Fe)/g-C_(3)N_(4))(MOF/Carbon nitride)and ternary(NH_(2)-MIL-88B(Fe)/g-C_(3)N_(4)/GO)(MOF/Carbon nitr...Herein,binary and ternary MOF/carbon based composites(MOF/Carbon nitride/Graphene oxide)(novel binary(NH_(2)-MIL-88B(Fe)/g-C_(3)N_(4))(MOF/Carbon nitride)and ternary(NH_(2)-MIL-88B(Fe)/g-C_(3)N_(4)/GO)(MOF/Carbon nitride/Graphene oxide)composites)were synthesized and used as photocatalysts for the elimination of Direct Red 23(D-Red23)and Tetracycline Hydrochloride(TC-H).NH_(2)-MIL-88B(Fe)/g-C_(3)N_(4)/GO(MILB/g/GO)ternary composites with three different amounts of GO including 3,7,and 11 wt%were synthesized and denoted as MILB/g/(3%)GO,MILB/g/(7%)GO,and MILB/g/(11%)GO.g-C_(3)N_(4)and GO(with three different amounts 3,7,and 11 wt%)were incorporated to synthesize MILB/g/(3%)GO,MILB/g/(7%)GO and MILB/g/(11%)GO ternary composites.Several analyses were used to characterize the materials.The MILB/g/(3%)GO demonstrated the highest pollutant degradation efficiency.The degradation rate of dye and Tetracycline after 70 min of light radiation using MILB/g/(3%)GO in a photo-Fenton-like reaction was about 99%and 96%,respectively.The creation of a heterojunction structure using g-C_(3)N_(4),and the simultaneous incorporation of the optimum amount of GO led to a remarkable amelioration in photocatalytic properties and the extraordinary performance of MILB/g/(3%)GO in the pollutants degradation process.展开更多
基金This work was supported by the National Natu-ral Science Foundation of China （No.21571166 and No.51271173） and the National Basic Research Pro- gram of China （No.2012CB922001）.
文摘Low-dimensional Bi2Fe4O9 nanosheets and microrods have been selectively prepared by a solvothermal method, from which the growth of the Bi2Fe4O9 crystals can be controlled by the variation of reaction conditions. Structure determination showed that the nanosheets are mainly exposed by {001} facets while the microrods are exposed by {110} facets. Ab- sorption spectra revealed that there are two bandgaps observed for both nanosheets （at 1.9 and 1.55 eV） and microrods （1.7 and 1.45 eV）, and they both would be available for the sunlight photocatalysis e ciently due to the intensive absorption ability in a wide region. Photocatalytic investigation demonstrated that the overall photocatalytic performance of the microrods is prior to that of the nanosheets due to the variation of bandgaps and exposed facets. The present report provides a useful alternative strategy for the controlling growth of nanostructures and/or microcrystals besides the present demonstration of the Bi2Fe4O9 crystals with diflerent bandgaps and facets that would be able to tune the corresponding photocatalytic ability selectively.
基金Supported by the National Natural Science Foundation of China under Grant Nos 61434002,61204097,11274214 and 51301099the National High-Tech Research and Development Program of China under Grant No 2014AA032904+1 种基金the Chang Jiang Scholars and Innovative Team Development Plan by the Ministry of Education under Grant No IRT1156the Specialized Research Fund for the Doctoral Program of Higher Education of China under Grant Nos 20121404130001 and 20121404120003
文摘The γ＇-Fe4N films on Cu underlayers are deposited on the glass and Si substrates by dc magnetron reactive sputtering. The effects of Cu underlayer on the structure, morphology and magnetic properties of the γ＇-Fe4N films are studied. The single-phase γ＇-Fe4N films with Cu underlayers on the glass substrate are obtained, while the mixture of Fe and γ＇-Fe4N is observed on the Si substrate. In comparison with the films without Cu underlayers, the grains of the films with Cu underlayers exhibit a non-uniform size distribution and give rise to a rougher surface. The magnetic measurements indicate that the γ＇-Fe4N films show a good soft ferromagnetic behavior. The enhanced coercivity in the films with Cu underlayers is observed due to the deterioration of the crystallographic structure as well as the rougher surface.
基金the Youth Innovation Promotion Association of the Chinese Academy of Sciences(Grant No.2015187)the National Natural Science Foundation of China(Grant Nos.11204338,and 11927807)the“Strategic Priority Research Program(B)”of the Chinese Academy of Sciences(Grant No.XDB04040300).Wei Li also acknowledges the start-up funding from Fudan University.
文摘Low-temperature specific heat(SH)is measured for the 12442-type KCa2Fe4As4F2 single crystal under different magnetic fields.A clear SH jump with the height of?C/T|Tc=130 mJ mol-1 K-2 is observed at the superconducting transition temperature Tc.It is found that the electronic SH coefficient?γ(H)quickly increases when the field is in the low-field region below 3T and then considerably slows down the increase with a further increase in the field,which indicates a rather strong anisotropy or multi-gap feature with a small minimum in the superconducting gap(s).The temperature-dependent SH data indicate the presence of the T2 term,which supplies further information and supports the picture with a line-nodal gap structure.Moreover,the onset point of the SH transition remains almost unchanged under the field as high as 9 T,which is similar to that observed in cuprates,and places this system in the middle between the BCS limit and the Bose-Einstein condensation.
文摘Ferromagnetic Fe3O4 nanoparticles were synthesized using water as the solvent through the sol-gel method, which was selected for its cost-effectiveness, simplicity, and eco-friendly nature. The synthesized nanoparticles were characterized using a variety of techniques, including Fourier Transform Infrared (FTIR) spectroscopy, X-ray powder diffraction (XRD), Scanning Electron Microscopy (SEM), Thermogravimetric Analysis (TGA), and Vibrating Sample Magnetometer (VSM). These characterizations confirmed the successful formation of Fe3O4 nanoparticles. The FTIR spectra identified characteristic peaks corresponding to the functional groups present, and XRD analysis, using Scherer’s equation, determined an average crystalline size of 1.2 nm for the Fe3O4 nanoparticles. TGA results demonstrated the thermal stability of the nanoparticles, SEM imaging revealed distinct honeycomb-like structures for the nanoparticles synthesized with water as the solvent, while the VSM analysis was used to determine the magnetic behavior of the nanoparticles.
基金This manuscript is extracted from project(981179017)funded by Institute for Color Science and Technology.
文摘Herein,binary and ternary MOF/carbon based composites(MOF/Carbon nitride/Graphene oxide)(novel binary(NH_(2)-MIL-88B(Fe)/g-C_(3)N_(4))(MOF/Carbon nitride)and ternary(NH_(2)-MIL-88B(Fe)/g-C_(3)N_(4)/GO)(MOF/Carbon nitride/Graphene oxide)composites)were synthesized and used as photocatalysts for the elimination of Direct Red 23(D-Red23)and Tetracycline Hydrochloride(TC-H).NH_(2)-MIL-88B(Fe)/g-C_(3)N_(4)/GO(MILB/g/GO)ternary composites with three different amounts of GO including 3,7,and 11 wt%were synthesized and denoted as MILB/g/(3%)GO,MILB/g/(7%)GO,and MILB/g/(11%)GO.g-C_(3)N_(4)and GO(with three different amounts 3,7,and 11 wt%)were incorporated to synthesize MILB/g/(3%)GO,MILB/g/(7%)GO and MILB/g/(11%)GO ternary composites.Several analyses were used to characterize the materials.The MILB/g/(3%)GO demonstrated the highest pollutant degradation efficiency.The degradation rate of dye and Tetracycline after 70 min of light radiation using MILB/g/(3%)GO in a photo-Fenton-like reaction was about 99%and 96%,respectively.The creation of a heterojunction structure using g-C_(3)N_(4),and the simultaneous incorporation of the optimum amount of GO led to a remarkable amelioration in photocatalytic properties and the extraordinary performance of MILB/g/(3%)GO in the pollutants degradation process.
