Novel hollow Fe3O4 nanoparticles for drug delivery were synthesized via a one-step template- free approach. These nanoparticles were obtained by modifing the Fe3O4 nanoparticles with 3-aminopropyltrimethoxy silane, an...Novel hollow Fe3O4 nanoparticles for drug delivery were synthesized via a one-step template- free approach. These nanoparticles were obtained by modifing the Fe3O4 nanoparticles with 3-aminopropyltrimethoxy silane, and then grafting alginate onto the surface of amine magnetic. The hollow structure of Fe3O4 spheres was characterized by TEM, XRD, and XPS. The M-H hysteresis loop indicated that the magnetic spheres exhibit snperparamagnetic characteristics at room temperature. Daunorubicin acting as a model drug was loaded into the carrier, and the maximum percent of envelop and load were 28.4% and 14.2% respectively. The drug controlled releasing behaviors of the carriers were compared in different pH media.展开更多
Transition metal oxides are promising candidates for the high-capacity anode material in lithium-ion batteries.The electrochemical performance of transition metal oxides can be improved by constructing suitable compos...Transition metal oxides are promising candidates for the high-capacity anode material in lithium-ion batteries.The electrochemical performance of transition metal oxides can be improved by constructing suitable composite architectures. Herein, we demonstrate a metal–organic framework(MOF)-assisted strategy for the synthesis of a hierarchical hybrid nanostructure composed of Fe_2O_3 nanotubes assembled in Co_3O_4 host. Starting from MOF composite precursors(Fe-based MOF encapsulated in a Cobased host matrix), a complex structure of Co_3O_4 host and engulfed Fe_2O_3 nanotubes was prepared by a simple annealing treatment in air. By virtue of their structural and compositional features, these hierarchical composite particles reveal enhanced lithium storage properties when employed as anodes for lithium-ion batteries.展开更多
As BiVO4 is one of the most popular visible-light-responding photocatalysts, it has been widely used for visiblelight-driven water splitting and environmental purification. However, the typical photocatalytic activity...As BiVO4 is one of the most popular visible-light-responding photocatalysts, it has been widely used for visiblelight-driven water splitting and environmental purification. However, the typical photocatalytic activity of unmodified BiVO4 for the degradation of organic pollutants is still not impressive. To address this limitation, we studied Fe2O3-modified porous BiVO4 nanoplates. Compared with unmodified BiVO4, the Fe2O3-modified porous Bi VO4 nanoplates showed significantly enhanced photocatalytic activities in decomposing both dye and colorless pollutant models, such as rhodamine B(Rh B) and phenol,respectively. The pseudo-first-order reaction rate constants for the degradation of RhB and phenol on Fe2O3-modified BiVO4 porous nanoplates are 27 and 31 times larger than that of pristine Bi VO4, respectively. We also found that the Fe2O3 may act as an efficient non-precious metal co-catalyst, which is responsible for the excellent photocatalytic activity of Fe2O3/BiVO4.Graphical Abstract Fe2O3, as a cheap and efficient co-catalyst, could greatly enhance the photocatalytic activity of Bi VO4 porous nanoplates in decomposing organic pollutants.展开更多
Lithium-sulfur batteries(LSBs) are regarded as a competitive next-generation energy storage device.However, their practical performance is seriously restricted due to the undesired polysulfides shuttling.Herein, a mul...Lithium-sulfur batteries(LSBs) are regarded as a competitive next-generation energy storage device.However, their practical performance is seriously restricted due to the undesired polysulfides shuttling.Herein, a multifunctional interlayer composed of paper-derived carbon(PC) scaffold, Fe3O4 nanoparticles,graphene, and graphite sheets is designed for applications in LSBs. The porous PC skeleton formed by the interweaving long-fibers not only facilitates fast transfer of Li ions and electrons but also provides a physical barrier for the polysulfide shuttling. The secondary Fe3O4@graphene component can reduce the polarization, boost the attachment of polysulfides, and promote the charging-discharging kinetics. The outer graphitic sheets layers benefit the interfacial electrochemistry and the utilization of S-containing species.The efficient obstruction of polysulfides diffusion is further witnessed via in situ ultraviolet-visible characterization and first-principles simulations. When 73% sulfur/commercial acetylene black is used as the cathode, the cell exhibits excellent capacity retention with high capacities at 0.5 C for 1000 cycles and even up to 10 C for 500 cycles, an ultrahigh rate capability up to 10 C(478 m Ah g-1), and a high arealsulfur loading of 8.05 mg cm-2. The strategy paves the way for developing multifunctional composites for LSBs with superior performance.展开更多
Fe3O4 magnetic nanoparticles(MNPs) were synthesised, characterised, and used as a peroxidase mimetic to accelerate levofloxacin sono-degradation in an ultrasound(US)/H2O2 system. The Fe3O4 MNPs were in nanometre scale...Fe3O4 magnetic nanoparticles(MNPs) were synthesised, characterised, and used as a peroxidase mimetic to accelerate levofloxacin sono-degradation in an ultrasound(US)/H2O2 system. The Fe3O4 MNPs were in nanometre scale with an average diameter of approximately 12 to 18 nm. The introduction of Fe3O4 MNPs increased levofloxacin sono-degradation in the US/H2O2 system. Experimental parameters, such as Fe3O4 MNP dose, initial solution p H, and H2O2 concentration, were investigated by a one-factor-at-a-time approach. The results showed that Fe3O4 MNPs enhanced levofloxacin removal in the p H range from 4.0 to 9.0. Levofloxacin removal ratio increased with Fe3O4 MNP dose up to 1.0 g·L-1and with H2O2 concentration until reaching the maximum. Moreover, three main intermediate compounds were identified by HPLC with electrospray ionisation tandem mass spectrometry, and a possible degradation pathway was proposed. This study suggests that combination of H2O2, Fe3O4 MNPs and US is a good way to improve the degradation efficiency of antibiotics.展开更多
In order to investigate the impedance matching properties of microwave absorbers,the ternary nanocomposites of GO/PANI/Fe3O4(GPF) are prepared via a two-step method,GO/PANI composites are synthesized by dilute polym...In order to investigate the impedance matching properties of microwave absorbers,the ternary nanocomposites of GO/PANI/Fe3O4(GPF) are prepared via a two-step method,GO/PANI composites are synthesized by dilute polymerization in the presence of aniline monomer and GO,and GO/PANI/Fe3O4 is prepared via a co-precipitation method.The obtained nanocomposites are characterized by scanning electron microscopy(SEM),X-ray diffraction(XRD),and Fourier transform infrared spectroscopy(FTIR),respectively.The microwave absorbability reveals enhanced microwave absorption properties compared with GO,PANI,and GO/PANI.The maximum reflection loss of GO/PANI/Fe3O4 is up to-27 dB at 14 GHz with its thickness being 2 mm,and its absorption bandwidths exceeding-10 dB are more than 11.2 GHz with its thickness values being in the range from 1.5 mm-4 mm.It provides that GO/PANI/Fe3O4 can be used as an attractive candidate for microwave absorbers.展开更多
The modification of graphitic carbon nitride can significantly improve the photocatalytic performance of graphitic carbon nitride(g-C3N4).Fe2O3/nitrogen-deficient g-C3N4-x composite catalysts were prepared with dicyan...The modification of graphitic carbon nitride can significantly improve the photocatalytic performance of graphitic carbon nitride(g-C3N4).Fe2O3/nitrogen-deficient g-C3N4-x composite catalysts were prepared with dicyandiamide as the precursor and Fe3+doped in this study.The composite catalysts were characterized by XRD,SEM,FT-IR,XPS and photocurrent measurements.Close interaction occurred between Fe2O3 and nitrogen deficient g-C3N4-x,more photogenerated electrons were created and effectively separated from the holes,resulting in a decrease of photocarrier recombination,and thus enhancing the photocurrent.Photocatalytic performance experiments showed that Fe2O3/nitrogen deficient g-C3N4-x could utilize lowenergy visible light more efficiently than pure g-C3N4,and the removal rate was 92%in 60 minutes.展开更多
A magnetic metal organic framework(MMOF) was synthesized and used to separate Sr^2+ in aqueous solution. The shape and structure of prepared Fe3O4@UiO-66-NH2 were characterized, and the absorbed concentration of st...A magnetic metal organic framework(MMOF) was synthesized and used to separate Sr^2+ in aqueous solution. The shape and structure of prepared Fe3O4@UiO-66-NH2 were characterized, and the absorbed concentration of strontium was determined through inductively coupled plasma mass spectrometry. The results indicated that Fe3O4 and UiO-66-NH2 combined through chemical bonding. The experimental adsorption results for separation of Sr^2+ in aqueous solution indicated that the adsorption of Sr^2+ to Fe3O4@UiO-66-NH2 increased drastically from pH 11 to pH 13. The adsorption isotherm model indicated that the adsorption of Sr^2+ conformed to the Freundlich isotherm model(R2 = 0.9919). The MMOF thus inherited the superior qualities of magnetic composites and metal organic frameworks, and can easily be separated under an external magnetic field. This MMOF thus has potential applications as a magnetic adsorbent for low level radionuclide (90)Sr.展开更多
Carbon-coated Fe3O4( Fe3O4/C) microspheres activated with 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride(EDC) were prepared, characterized and applied to adsorb bovine serum albumin(BSA). The pre...Carbon-coated Fe3O4( Fe3O4/C) microspheres activated with 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride(EDC) were prepared, characterized and applied to adsorb bovine serum albumin(BSA). The prepared magnetic microspheres had spherical core-shell structure with a uniform and continuous carbon coating coupled with activation by EDC, and possessed superparamagnetic characteristics. The experimental results showed that the adsorption amount of BSA on the EDC-activated Fe3O4/C(Fe3O4/C-EDC) microspheres was higher than that on the Fe3O4/C microspheres. The maximum adsorption of BSA on Fe3O4/C-EDC microspheres occurred at pH 4.7, which was the isoelectric point of BSA. At low concentrations(below 1.0 M), salt had no noticeable effect on BSA adsorption. The BSA adsorption of Fe3O4/C-EDC microspheres had a better fit to the Langmuir model than the Freundlich isotherm and Temkin isotherm model, and the kinetic data were well described by the pseudo-second-order model. The adsorption equilibrium could be reached within 20 min. High desorption efficiency(97.6%) of BSA from Fe3O4/C-EDC microspheres was obtained with 0.5 M Na2HPO4(pH 9.4) as the desorbent.展开更多
Spent pickling liquors pose a serious environmental problem in most industrialized countries, mainly owing to their corrosive properties and their ferrous iron and hydrochloric acid content. In this paper, spent pickl...Spent pickling liquors pose a serious environmental problem in most industrialized countries, mainly owing to their corrosive properties and their ferrous iron and hydrochloric acid content. In this paper, spent pickling liquor was used as an inexpensive raw material to prepare Fe304 magnetic powder via an oxidation method. Being able to recover the dissolved iron from spent pickling liquors would not only salvage a valuable material but also render the effluent environmentally benign. The structure of the Fe_3O_4 magnetic powder was characterized by X-ray diffraction. The morphology and size were characterized by scanning electron microscopy and transmission electron microscopy. Their magnetic properties were tested at room temperature by a vibrating sample magnetometer. In addition, the saturation magnetization of Fe_3 O_4 products can be further enhanced to 96.1 emu/g after purification.展开更多
文摘Novel hollow Fe3O4 nanoparticles for drug delivery were synthesized via a one-step template- free approach. These nanoparticles were obtained by modifing the Fe3O4 nanoparticles with 3-aminopropyltrimethoxy silane, and then grafting alginate onto the surface of amine magnetic. The hollow structure of Fe3O4 spheres was characterized by TEM, XRD, and XPS. The M-H hysteresis loop indicated that the magnetic spheres exhibit snperparamagnetic characteristics at room temperature. Daunorubicin acting as a model drug was loaded into the carrier, and the maximum percent of envelop and load were 28.4% and 14.2% respectively. The drug controlled releasing behaviors of the carriers were compared in different pH media.
文摘Transition metal oxides are promising candidates for the high-capacity anode material in lithium-ion batteries.The electrochemical performance of transition metal oxides can be improved by constructing suitable composite architectures. Herein, we demonstrate a metal–organic framework(MOF)-assisted strategy for the synthesis of a hierarchical hybrid nanostructure composed of Fe_2O_3 nanotubes assembled in Co_3O_4 host. Starting from MOF composite precursors(Fe-based MOF encapsulated in a Cobased host matrix), a complex structure of Co_3O_4 host and engulfed Fe_2O_3 nanotubes was prepared by a simple annealing treatment in air. By virtue of their structural and compositional features, these hierarchical composite particles reveal enhanced lithium storage properties when employed as anodes for lithium-ion batteries.
基金partial financial support from NSFC(51372173,51002107,and21173159)NSFC for Distinguished Young Scholars(51025207)+3 种基金Research Climb Plan of ZJED(pd2013383)Opening Project of State Key Laboratory of High Performance Ceramics and Superfine Microstructure(SKL201409SIC)Xinmiao talent project of Zhejiang Province(2013R424060)College Students Research Project of Wenzhou University(14xk193)
文摘As BiVO4 is one of the most popular visible-light-responding photocatalysts, it has been widely used for visiblelight-driven water splitting and environmental purification. However, the typical photocatalytic activity of unmodified BiVO4 for the degradation of organic pollutants is still not impressive. To address this limitation, we studied Fe2O3-modified porous BiVO4 nanoplates. Compared with unmodified BiVO4, the Fe2O3-modified porous Bi VO4 nanoplates showed significantly enhanced photocatalytic activities in decomposing both dye and colorless pollutant models, such as rhodamine B(Rh B) and phenol,respectively. The pseudo-first-order reaction rate constants for the degradation of RhB and phenol on Fe2O3-modified BiVO4 porous nanoplates are 27 and 31 times larger than that of pristine Bi VO4, respectively. We also found that the Fe2O3 may act as an efficient non-precious metal co-catalyst, which is responsible for the excellent photocatalytic activity of Fe2O3/BiVO4.Graphical Abstract Fe2O3, as a cheap and efficient co-catalyst, could greatly enhance the photocatalytic activity of Bi VO4 porous nanoplates in decomposing organic pollutants.
基金the financial supports provided by the National Natural Science Foundation of China (Nos. 21971145, 21601108)the Taishan Scholar Project Foundation of Shandong Province (ts20190908)+1 种基金the Natural Science Foundation of Shandong Province (ZR2019MB024)Young Scholars Program of Shandong University (2017WLJH15)。
文摘Lithium-sulfur batteries(LSBs) are regarded as a competitive next-generation energy storage device.However, their practical performance is seriously restricted due to the undesired polysulfides shuttling.Herein, a multifunctional interlayer composed of paper-derived carbon(PC) scaffold, Fe3O4 nanoparticles,graphene, and graphite sheets is designed for applications in LSBs. The porous PC skeleton formed by the interweaving long-fibers not only facilitates fast transfer of Li ions and electrons but also provides a physical barrier for the polysulfide shuttling. The secondary Fe3O4@graphene component can reduce the polarization, boost the attachment of polysulfides, and promote the charging-discharging kinetics. The outer graphitic sheets layers benefit the interfacial electrochemistry and the utilization of S-containing species.The efficient obstruction of polysulfides diffusion is further witnessed via in situ ultraviolet-visible characterization and first-principles simulations. When 73% sulfur/commercial acetylene black is used as the cathode, the cell exhibits excellent capacity retention with high capacities at 0.5 C for 1000 cycles and even up to 10 C for 500 cycles, an ultrahigh rate capability up to 10 C(478 m Ah g-1), and a high arealsulfur loading of 8.05 mg cm-2. The strategy paves the way for developing multifunctional composites for LSBs with superior performance.
基金Supported by the National Natural Science Foundation of China(51009115)Shaanxi Provincial Department of Education Key Laboratory Project(13JS067)+2 种基金the Hall of Shaanxi Province Science and Technology(2013JK0881)the Research Plan Project of Water Resources Department of Shaanxi Province(2013slkj-07)the Innovation of Science and Technology Fund of Xi'an University of Technology(211302)
文摘Fe3O4 magnetic nanoparticles(MNPs) were synthesised, characterised, and used as a peroxidase mimetic to accelerate levofloxacin sono-degradation in an ultrasound(US)/H2O2 system. The Fe3O4 MNPs were in nanometre scale with an average diameter of approximately 12 to 18 nm. The introduction of Fe3O4 MNPs increased levofloxacin sono-degradation in the US/H2O2 system. Experimental parameters, such as Fe3O4 MNP dose, initial solution p H, and H2O2 concentration, were investigated by a one-factor-at-a-time approach. The results showed that Fe3O4 MNPs enhanced levofloxacin removal in the p H range from 4.0 to 9.0. Levofloxacin removal ratio increased with Fe3O4 MNP dose up to 1.0 g·L-1and with H2O2 concentration until reaching the maximum. Moreover, three main intermediate compounds were identified by HPLC with electrospray ionisation tandem mass spectrometry, and a possible degradation pathway was proposed. This study suggests that combination of H2O2, Fe3O4 MNPs and US is a good way to improve the degradation efficiency of antibiotics.
基金supported by the National Basic Research Program of China(Grant Nos.2011CB932700 and 2011CB932703)the National Natural Science Foundation of China(Grant Nos.61335006,61378073,and 61077044)+1 种基金the Beijing Natural Science Foundation,China(Grant No.4132031)the Fundamental Research Funds for the Central Universities of Beijing Jiaotong University,China(Grant No.2014YJS136)
文摘In order to investigate the impedance matching properties of microwave absorbers,the ternary nanocomposites of GO/PANI/Fe3O4(GPF) are prepared via a two-step method,GO/PANI composites are synthesized by dilute polymerization in the presence of aniline monomer and GO,and GO/PANI/Fe3O4 is prepared via a co-precipitation method.The obtained nanocomposites are characterized by scanning electron microscopy(SEM),X-ray diffraction(XRD),and Fourier transform infrared spectroscopy(FTIR),respectively.The microwave absorbability reveals enhanced microwave absorption properties compared with GO,PANI,and GO/PANI.The maximum reflection loss of GO/PANI/Fe3O4 is up to-27 dB at 14 GHz with its thickness being 2 mm,and its absorption bandwidths exceeding-10 dB are more than 11.2 GHz with its thickness values being in the range from 1.5 mm-4 mm.It provides that GO/PANI/Fe3O4 can be used as an attractive candidate for microwave absorbers.
基金Supported by the Fuling Shale Gas Environmental Exploration Technology of National Science and Technology Special Project(No.2016ZX05060)the Demonstration of Integrated Management of Rocky Desertification and Enhancement of Ecological Service Function in Karst Peak-cluster Depression(No.2016YFC0502400)National Natural Science Foundation of China(No.51709254)
文摘The modification of graphitic carbon nitride can significantly improve the photocatalytic performance of graphitic carbon nitride(g-C3N4).Fe2O3/nitrogen-deficient g-C3N4-x composite catalysts were prepared with dicyandiamide as the precursor and Fe3+doped in this study.The composite catalysts were characterized by XRD,SEM,FT-IR,XPS and photocurrent measurements.Close interaction occurred between Fe2O3 and nitrogen deficient g-C3N4-x,more photogenerated electrons were created and effectively separated from the holes,resulting in a decrease of photocarrier recombination,and thus enhancing the photocurrent.Photocatalytic performance experiments showed that Fe2O3/nitrogen deficient g-C3N4-x could utilize lowenergy visible light more efficiently than pure g-C3N4,and the removal rate was 92%in 60 minutes.
基金financially supported by the National Natural Science Foundation of China[Grant No.20477058]by the Chinese Ministry of Science and Technology[Grant No.2014YF211000]
文摘A magnetic metal organic framework(MMOF) was synthesized and used to separate Sr^2+ in aqueous solution. The shape and structure of prepared Fe3O4@UiO-66-NH2 were characterized, and the absorbed concentration of strontium was determined through inductively coupled plasma mass spectrometry. The results indicated that Fe3O4 and UiO-66-NH2 combined through chemical bonding. The experimental adsorption results for separation of Sr^2+ in aqueous solution indicated that the adsorption of Sr^2+ to Fe3O4@UiO-66-NH2 increased drastically from pH 11 to pH 13. The adsorption isotherm model indicated that the adsorption of Sr^2+ conformed to the Freundlich isotherm model(R2 = 0.9919). The MMOF thus inherited the superior qualities of magnetic composites and metal organic frameworks, and can easily be separated under an external magnetic field. This MMOF thus has potential applications as a magnetic adsorbent for low level radionuclide (90)Sr.
基金Funded by the Major Science and Technology Program for Water Pollution Control and Treatment(No.2013ZX07202-010)
文摘Carbon-coated Fe3O4( Fe3O4/C) microspheres activated with 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride(EDC) were prepared, characterized and applied to adsorb bovine serum albumin(BSA). The prepared magnetic microspheres had spherical core-shell structure with a uniform and continuous carbon coating coupled with activation by EDC, and possessed superparamagnetic characteristics. The experimental results showed that the adsorption amount of BSA on the EDC-activated Fe3O4/C(Fe3O4/C-EDC) microspheres was higher than that on the Fe3O4/C microspheres. The maximum adsorption of BSA on Fe3O4/C-EDC microspheres occurred at pH 4.7, which was the isoelectric point of BSA. At low concentrations(below 1.0 M), salt had no noticeable effect on BSA adsorption. The BSA adsorption of Fe3O4/C-EDC microspheres had a better fit to the Langmuir model than the Freundlich isotherm and Temkin isotherm model, and the kinetic data were well described by the pseudo-second-order model. The adsorption equilibrium could be reached within 20 min. High desorption efficiency(97.6%) of BSA from Fe3O4/C-EDC microspheres was obtained with 0.5 M Na2HPO4(pH 9.4) as the desorbent.
基金supported by the project of Synthesis of Iron Oxide Red from Waste Acid(No.2016GIF-0035)
文摘Spent pickling liquors pose a serious environmental problem in most industrialized countries, mainly owing to their corrosive properties and their ferrous iron and hydrochloric acid content. In this paper, spent pickling liquor was used as an inexpensive raw material to prepare Fe304 magnetic powder via an oxidation method. Being able to recover the dissolved iron from spent pickling liquors would not only salvage a valuable material but also render the effluent environmentally benign. The structure of the Fe_3O_4 magnetic powder was characterized by X-ray diffraction. The morphology and size were characterized by scanning electron microscopy and transmission electron microscopy. Their magnetic properties were tested at room temperature by a vibrating sample magnetometer. In addition, the saturation magnetization of Fe_3 O_4 products can be further enhanced to 96.1 emu/g after purification.