We report on the synthesis of Sn-doped hematite nanoparticles(Sn-α-Fe_(2)O_(3) NPs)by the hydrothermal method.The prepared Sn-α-Fe_(2)O_(3) NPs had a highly pure and well crystalline rhombohedral phase with an avera...We report on the synthesis of Sn-doped hematite nanoparticles(Sn-α-Fe_(2)O_(3) NPs)by the hydrothermal method.The prepared Sn-α-Fe_(2)O_(3) NPs had a highly pure and well crystalline rhombohedral phase with an average particle size of 41.4 nm.The optical properties of as-synthesizedα-Fe_(2)O_(3) NPs show a higher bandgap energy(2.40-2.57 eV)than that of pure bulkα-Fe_(2)O_(3)(2.1 eV).By doping Sn intoα-Fe_(2)O_(3) NPs,the Sn-doped hematite was observed a redshift toward a long wavelength with in-creasing Sn concentration from 0%to 4.0%.The photocatalytic activity of Sn-dopedα-Fe_(2)O_(3) NPs was evaluated by Congo red(CR)dye degradation.The degradation efficiency of CR dye using Sn-α-Fe_(2)O_(3) NPs catalyst is higher than that of pureα-Fe_(2)O_(3) NPs.The highest degradation efficiency of CR dye was 97.8%using 2.5%Sn-dopedα-Fe_(2)O_(3) NPs catalyst under visible-light irradi-ation.These results suggest that the synthesized Sn-dopedα-Fe_(2)O_(3) nanoparticles might be a suitable approach to develop a photocatalytic degradation of toxic inorganic dye in wastewater.展开更多
Superwetting materials have drawn unprecedented attention in the treatment of oily wastewater due to their preferable anti-fouling property and selective oil/water separation.However,it is still a challenge to fabrica...Superwetting materials have drawn unprecedented attention in the treatment of oily wastewater due to their preferable anti-fouling property and selective oil/water separation.However,it is still a challenge to fabricate multifunctional and environmentally friendly materials,which can be stably applied to purify the actual complicated wastewater.Here,a Ag/Ag/α-Fe_(2)O_(3) heterostructure anchored copper mesh was intentionally synthesized using a facile two-step hydrothermal method.The resultant mesh with superhydrophilicity and underwater superoleophobicity was capable of separating various oil/water mixtures with superior separation efficiency and high permeationflux driven by gravity.Benefiting from the joint effects of the smaller band gap of Ag/α-Fe_(2)O_(3) heterojunction,inherent antibacterial capacity of Ag/α-Fe_(2)O_(3) and Ag nanoparticles,favorable conductive substrate,as well as the hierarchical structure with superwettability,such mesh presented remarkably enhanced degradation capability toward organic dyes under visible light irradiation and antibacterial activity against both Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)compared with the pure Ag/α-Fe_(2)O_(3) coated mesh.Impressively,the mesh exhibited bifunctional water purification performance,in which organic dyes were eliminated simultaneously from water during oil/water separation in onefiltration process.More importantly,this mesh behaved exceptional chemical resistance,mechanical stability and long-term reusability.Therefore,this material with multifunctional integration may hold promising potential for steady water purification in practice.展开更多
In order to explore the stability of a liquid crystal(LC)system doped withγ-Fe_(2)O_(3)nanoparticles,the physical properties(clearing point,dielectric properties),electro-optical properties and residual direct-curren...In order to explore the stability of a liquid crystal(LC)system doped withγ-Fe_(2)O_(3)nanoparticles,the physical properties(clearing point,dielectric properties),electro-optical properties and residual direct-current voltage(RDCV)of the doped LC system were measured and evaluated at different times.First,the temperature was controlled by precision hot stage,and the clearing point temperature of doped LC was observed and measured by a polarized optical microscope.Using a precision LCR meter,we measured the capacitance-voltage curves of the doped LC system at the temperature of 27℃.The dielectric constant of doped LC was calculated by the dualcell capacitance method.Then,the electro-optical properties of the doped LC system were measured.Finally,the RDCV of the doped LC system was measured and calculated.After five months,the parameters of the doped LC system were re-measured and analyzed under the same conditions to evaluate its stability.The experimental results show that,within five months,the clearing point change rate of doped LC is in the range of 0.24%-1.37%,the change of dielectric anisotropy is in the range of 0.035-0.2,the curves of electro-optical properties are basically fitted,and the change rate of saturated RDCV is about 11.2%,which basically indicate that the LC system doped withγ-Fe_(2)O_(3)nanoparticles has good stability.展开更多
Y_2O_3 ultrafine particles have been prepared by means of precipitation in Japan and U.S.A., and ultrafine particles of rare earth oxide have been prepared with dicarboxyl precipitate by Wang Zenglin et al. It has not...Y_2O_3 ultrafine particles have been prepared by means of precipitation in Japan and U.S.A., and ultrafine particles of rare earth oxide have been prepared with dicarboxyl precipitate by Wang Zenglin et al. It has not been reported, however, to prepare La_2O_3 ultrafine particles with urea as the hydrolytic agent. This method is easy to operate, and the materials are cheap and easily available, besides, it is easy to obtain homogeneous spherical precursors of ultrafine particles. The present, paper describes the preparation of La_2O_3 ultrafine particles with urea as hydrolytic agent, and observes some of its characteristics.展开更多
Nano-AlN and submicron-Al_(2)O_(3) particles were simultaneously utilized in a 6061 Al matrix composite to improve the high-temperature strength.According to the SEM and TEM characterization,nano-AlN and submicron-Al_...Nano-AlN and submicron-Al_(2)O_(3) particles were simultaneously utilized in a 6061 Al matrix composite to improve the high-temperature strength.According to the SEM and TEM characterization,nano-AlN and submicron-Al_(2)O_(3) particles are uniformly distributed in the Al matrix.Brinell hardness results indicate that different from the traditional 6061 Al matrix alloy,the aging kinetics of the composite is obviously accelerated by the reinforcement particles.The T6-treated composite exhibits excellent tensile properties at both room temperature and elevated temperature.Especially at 350℃,the T6-treated composite not only has a high yield strength of 121 MPa and ultimate tensile strength of 128 MPa,but also exhibits a large elongation of 11.6%.Different strengthening mechanisms of nano-AlN and submicron-Al_(2)O_(3) particles were also discussed in detail.展开更多
Photocatalytic water splitting for hydrogen production(H_(2))is one of the main potential applications of photocatalytic technology,which can use solar energy as the energy required for chemical reactions to alleviate...Photocatalytic water splitting for hydrogen production(H_(2))is one of the main potential applications of photocatalytic technology,which can use solar energy as the energy required for chemical reactions to alleviate the energy crisis.In this work,zero-dimensional/two-dimensional(0D/2D)contact surface CdS/α-Fe_(2)O_(3)(CF)heterojunction photocatalyst was synthesized via a simple solvothermal method.Photocatalytic hydrogen production experiments revealed that the CF-15 sample shows the optimal photocatalytic H_(2)rate(1806μmol·h^(-1)·g^(-1))and apparent quantum efficiency(AQE=13.7%atλ=420 nm).The enhancement of photocatalytic performance is mainly attributed to the contact of 0D/2D interface and the synergistic effect of Z-scheme electron transfer mechanism.This work provides an effective way for modified composite semiconductor photocatalyst by constructing special interface heterojunction to achieve highly efficiently catalysis.展开更多
基金the financial support of Vietnam Academy of Science and Technology under project VAST01.04/18-19.
文摘We report on the synthesis of Sn-doped hematite nanoparticles(Sn-α-Fe_(2)O_(3) NPs)by the hydrothermal method.The prepared Sn-α-Fe_(2)O_(3) NPs had a highly pure and well crystalline rhombohedral phase with an average particle size of 41.4 nm.The optical properties of as-synthesizedα-Fe_(2)O_(3) NPs show a higher bandgap energy(2.40-2.57 eV)than that of pure bulkα-Fe_(2)O_(3)(2.1 eV).By doping Sn intoα-Fe_(2)O_(3) NPs,the Sn-doped hematite was observed a redshift toward a long wavelength with in-creasing Sn concentration from 0%to 4.0%.The photocatalytic activity of Sn-dopedα-Fe_(2)O_(3) NPs was evaluated by Congo red(CR)dye degradation.The degradation efficiency of CR dye using Sn-α-Fe_(2)O_(3) NPs catalyst is higher than that of pureα-Fe_(2)O_(3) NPs.The highest degradation efficiency of CR dye was 97.8%using 2.5%Sn-dopedα-Fe_(2)O_(3) NPs catalyst under visible-light irradi-ation.These results suggest that the synthesized Sn-dopedα-Fe_(2)O_(3) nanoparticles might be a suitable approach to develop a photocatalytic degradation of toxic inorganic dye in wastewater.
基金This work was financially supported by the Shandong Provincial Natural Science Foundation(ZR2020QB116)the Excellent Young Talents Foundation in Universities of Anhui Province(gxyq2021223)the Key Research Project of Natural Science in Universities of Anhui Province.(KJ2020A0749).
文摘Superwetting materials have drawn unprecedented attention in the treatment of oily wastewater due to their preferable anti-fouling property and selective oil/water separation.However,it is still a challenge to fabricate multifunctional and environmentally friendly materials,which can be stably applied to purify the actual complicated wastewater.Here,a Ag/Ag/α-Fe_(2)O_(3) heterostructure anchored copper mesh was intentionally synthesized using a facile two-step hydrothermal method.The resultant mesh with superhydrophilicity and underwater superoleophobicity was capable of separating various oil/water mixtures with superior separation efficiency and high permeationflux driven by gravity.Benefiting from the joint effects of the smaller band gap of Ag/α-Fe_(2)O_(3) heterojunction,inherent antibacterial capacity of Ag/α-Fe_(2)O_(3) and Ag nanoparticles,favorable conductive substrate,as well as the hierarchical structure with superwettability,such mesh presented remarkably enhanced degradation capability toward organic dyes under visible light irradiation and antibacterial activity against both Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)compared with the pure Ag/α-Fe_(2)O_(3) coated mesh.Impressively,the mesh exhibited bifunctional water purification performance,in which organic dyes were eliminated simultaneously from water during oil/water separation in onefiltration process.More importantly,this mesh behaved exceptional chemical resistance,mechanical stability and long-term reusability.Therefore,this material with multifunctional integration may hold promising potential for steady water purification in practice.
基金Project supported by the Natural Science Foundation of Hebei Province of China (Grant Nos. A2019202235 and A2017202004)Research and Practice Project of Hebei Provincial Higher Education and Teaching Reform (Grant No. 2017GJJG018)+2 种基金Research Projects of Undergraduate Education and Teaching Reform in Hebei University of Technology (Grant No. 201802003)the Key Subject Construction Project of Hebei Provincial Universitiesthe Special Project of China Association of Higher Education (Grant No. 21LKYB05)
文摘In order to explore the stability of a liquid crystal(LC)system doped withγ-Fe_(2)O_(3)nanoparticles,the physical properties(clearing point,dielectric properties),electro-optical properties and residual direct-current voltage(RDCV)of the doped LC system were measured and evaluated at different times.First,the temperature was controlled by precision hot stage,and the clearing point temperature of doped LC was observed and measured by a polarized optical microscope.Using a precision LCR meter,we measured the capacitance-voltage curves of the doped LC system at the temperature of 27℃.The dielectric constant of doped LC was calculated by the dualcell capacitance method.Then,the electro-optical properties of the doped LC system were measured.Finally,the RDCV of the doped LC system was measured and calculated.After five months,the parameters of the doped LC system were re-measured and analyzed under the same conditions to evaluate its stability.The experimental results show that,within five months,the clearing point change rate of doped LC is in the range of 0.24%-1.37%,the change of dielectric anisotropy is in the range of 0.035-0.2,the curves of electro-optical properties are basically fitted,and the change rate of saturated RDCV is about 11.2%,which basically indicate that the LC system doped withγ-Fe_(2)O_(3)nanoparticles has good stability.
文摘Y_2O_3 ultrafine particles have been prepared by means of precipitation in Japan and U.S.A., and ultrafine particles of rare earth oxide have been prepared with dicarboxyl precipitate by Wang Zenglin et al. It has not been reported, however, to prepare La_2O_3 ultrafine particles with urea as the hydrolytic agent. This method is easy to operate, and the materials are cheap and easily available, besides, it is easy to obtain homogeneous spherical precursors of ultrafine particles. The present, paper describes the preparation of La_2O_3 ultrafine particles with urea as hydrolytic agent, and observes some of its characteristics.
基金supported by the Key Program of National Natural Science Foundation of China(No.51731007)the National Natural Science Foundation of China(No.52071179)the Fundamental Research Funds for the Central Universities(No.30920021160).
文摘Nano-AlN and submicron-Al_(2)O_(3) particles were simultaneously utilized in a 6061 Al matrix composite to improve the high-temperature strength.According to the SEM and TEM characterization,nano-AlN and submicron-Al_(2)O_(3) particles are uniformly distributed in the Al matrix.Brinell hardness results indicate that different from the traditional 6061 Al matrix alloy,the aging kinetics of the composite is obviously accelerated by the reinforcement particles.The T6-treated composite exhibits excellent tensile properties at both room temperature and elevated temperature.Especially at 350℃,the T6-treated composite not only has a high yield strength of 121 MPa and ultimate tensile strength of 128 MPa,but also exhibits a large elongation of 11.6%.Different strengthening mechanisms of nano-AlN and submicron-Al_(2)O_(3) particles were also discussed in detail.
基金the founding support from the National Natural Science Foundation of China(21906072 and 22006057)the Natural Science Foundation of Jiangsu Province(BK20190982)+1 种基金“Doctor of Mass entrepreneurship and innovation”Project in Jiangsu ProvinceDoctoral Scientific Research Foundation of Jiangsu University of Science and Technology(China)(1062931806 and 1142931803)。
文摘Photocatalytic water splitting for hydrogen production(H_(2))is one of the main potential applications of photocatalytic technology,which can use solar energy as the energy required for chemical reactions to alleviate the energy crisis.In this work,zero-dimensional/two-dimensional(0D/2D)contact surface CdS/α-Fe_(2)O_(3)(CF)heterojunction photocatalyst was synthesized via a simple solvothermal method.Photocatalytic hydrogen production experiments revealed that the CF-15 sample shows the optimal photocatalytic H_(2)rate(1806μmol·h^(-1)·g^(-1))and apparent quantum efficiency(AQE=13.7%atλ=420 nm).The enhancement of photocatalytic performance is mainly attributed to the contact of 0D/2D interface and the synergistic effect of Z-scheme electron transfer mechanism.This work provides an effective way for modified composite semiconductor photocatalyst by constructing special interface heterojunction to achieve highly efficiently catalysis.
