Two important iron oxides: Fe304 and Fe203, as well as Fe304 and Fe203 nanoparticles mingling with Ag were successfully synthesized via a hydrothermal procedure. The samples were confirmed and characterized by X-ray ...Two important iron oxides: Fe304 and Fe203, as well as Fe304 and Fe203 nanoparticles mingling with Ag were successfully synthesized via a hydrothermal procedure. The samples were confirmed and characterized by X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The morphology of the samples was observed by transmission electron microscopy (TEM). The results indicated Fe304, Fe203, Ag/Fe304 and Ag/Fe203 samples all were nanoparticles with smaller sizes. The samples were modified on a glassy carbon electrode and their elctrocatalytic properties for p-nitropbenol in a basic solution were investigated. The results revealed all the samples showed enhanced catalytic performances by comparison with a bare glassy carbon electrode. Furthermore, p-nitrophenol could be reduced at a lower peak potential or a higher peak current on a glassy carbon electrode modified with Ag/Fe304 or Ag/Fe203 composite nanoparticles.展开更多
Some factors effected on heterogeneous hydrothermal stripping from iron-loaded organic phase of naphthenic acid-isooctyl alcohol-kerosene,such as the concentrations of initial iron and naphthenic acid,the weight of&qu...Some factors effected on heterogeneous hydrothermal stripping from iron-loaded organic phase of naphthenic acid-isooctyl alcohol-kerosene,such as the concentrations of initial iron and naphthenic acid,the weight of"seed"of Fe2O3,temperature and time,were investigated.The process rate equation and the relation between stripping percent and time needed were established.The results showed the proces activation energy was 114 kJ·mol-1 and the heterogeneous hydrothermal stripping was controlled by the hydrolysis of naphthenic compound of iron.展开更多
To improve the initial coulombic efficiency and bulk density of ordered mesoporous carbons, active Fe203 nanoparticles were introduced into tubular mesopore channels of CMK-5 carbon, which possesses high specific surf...To improve the initial coulombic efficiency and bulk density of ordered mesoporous carbons, active Fe203 nanoparticles were introduced into tubular mesopore channels of CMK-5 carbon, which possesses high specific surface area (〉1700 m2.g-1) and large pore volume (〉1.8 cm3-g-1). Fine Fe203 nanoparticles with sizes in the range of 5-7 nm were highly and homogenously encapsulated into CMK-5 matrix through ammonia-treatment and subsequent pyrolysis method. The Fe203 loading was carefully tailored and designed to warrant a high Fe203 content and adequate buffer space for improving the electrochemical performance. In particular, such Fe203 and mesoporous carbon composite with 47 wt% loading exhibits a considerably stable cycle performance (683 mAh.g-1 after 100 cycles, 99% capacity retention against that of the second cycle) as well as good rate capability. The fabrication strategy can effectively solve the drawback of single material, and achieve a high-performance lithium electrode material.展开更多
Iron oxide nanoparticles are the most popular magnetic nanoparticles used in biomedical applications due to their low cost, low toxicity, and unique magnetic property. Magnetic iron oxide nanoparticles, including magn...Iron oxide nanoparticles are the most popular magnetic nanoparticles used in biomedical applications due to their low cost, low toxicity, and unique magnetic property. Magnetic iron oxide nanoparticles, including magnetite (Fe304) and maghemite (γ-Fe203), usually exhibit a superparamagnetic property as their size goes smaller than 20 nm, which are often denoted as superparamagnetic iron oxide nanoparticles (SPIONs) and utilized for drug delivery, diagnosis, therapy, and etc. This review article gives a brief introduction on magnetic iron oxide nanoparticles in terms of their fundamentals of magnetism, magnetic resonance imaging (MRI), and drug delivery, as well as the synthesis approaches, surface coating, and application examples from recent key literatures. Because the quality and surface chemistry play important roles in biomedical applications, our review focuses on the synthesis approaches and surface modifications of iron oxide nanopar- ticles. We aim to provide a detailed introduction to readers who are new to this field, helping them to choose suitable synthesis methods and to optimize the surface chemistry of iron oxide nanoparticles for their interests.展开更多
The hybrid particles composed of hydroxyapatite (HAp) and ferrite ( γ-Fe203) were synthesized by two-step precipitation method. The effect of reaction temperature on the morphology of the hybrids was also studied...The hybrid particles composed of hydroxyapatite (HAp) and ferrite ( γ-Fe203) were synthesized by two-step precipitation method. The effect of reaction temperature on the morphology of the hybrids was also studied. The resultant hybrids were characterized by transmission electron microscopy (TEM) and X-ray diffraction analysis(XRD). It was found that γ-Fe203 nanoparticles dispersed within the HAp matrix and these hybrids had a feather-like or spherical morphology when synthesized at 90 ℃ or room temperature, respectively. The magnetic properties of the hybrid showed good superparamagnetic feature, and they could be controlled by the external magnetic field.展开更多
文摘Two important iron oxides: Fe304 and Fe203, as well as Fe304 and Fe203 nanoparticles mingling with Ag were successfully synthesized via a hydrothermal procedure. The samples were confirmed and characterized by X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The morphology of the samples was observed by transmission electron microscopy (TEM). The results indicated Fe304, Fe203, Ag/Fe304 and Ag/Fe203 samples all were nanoparticles with smaller sizes. The samples were modified on a glassy carbon electrode and their elctrocatalytic properties for p-nitropbenol in a basic solution were investigated. The results revealed all the samples showed enhanced catalytic performances by comparison with a bare glassy carbon electrode. Furthermore, p-nitrophenol could be reduced at a lower peak potential or a higher peak current on a glassy carbon electrode modified with Ag/Fe304 or Ag/Fe203 composite nanoparticles.
文摘Some factors effected on heterogeneous hydrothermal stripping from iron-loaded organic phase of naphthenic acid-isooctyl alcohol-kerosene,such as the concentrations of initial iron and naphthenic acid,the weight of"seed"of Fe2O3,temperature and time,were investigated.The process rate equation and the relation between stripping percent and time needed were established.The results showed the proces activation energy was 114 kJ·mol-1 and the heterogeneous hydrothermal stripping was controlled by the hydrolysis of naphthenic compound of iron.
基金supported by the Fundamental Research Funds for the Central Universities (Grant No. DUT12ZD218)the National Natural Science Foundation of China (Grant No. 21103184)the Ph. D. Programs Foundation (Grant No. 20100041110017) of Ministry of Education of China
文摘To improve the initial coulombic efficiency and bulk density of ordered mesoporous carbons, active Fe203 nanoparticles were introduced into tubular mesopore channels of CMK-5 carbon, which possesses high specific surface area (〉1700 m2.g-1) and large pore volume (〉1.8 cm3-g-1). Fine Fe203 nanoparticles with sizes in the range of 5-7 nm were highly and homogenously encapsulated into CMK-5 matrix through ammonia-treatment and subsequent pyrolysis method. The Fe203 loading was carefully tailored and designed to warrant a high Fe203 content and adequate buffer space for improving the electrochemical performance. In particular, such Fe203 and mesoporous carbon composite with 47 wt% loading exhibits a considerably stable cycle performance (683 mAh.g-1 after 100 cycles, 99% capacity retention against that of the second cycle) as well as good rate capability. The fabrication strategy can effectively solve the drawback of single material, and achieve a high-performance lithium electrode material.
基金Project supported by Start-up Grant of Nanyang Technological UniversityTier 1 Grant of Ministry of Education,Singapore(RGT8/13)
文摘Iron oxide nanoparticles are the most popular magnetic nanoparticles used in biomedical applications due to their low cost, low toxicity, and unique magnetic property. Magnetic iron oxide nanoparticles, including magnetite (Fe304) and maghemite (γ-Fe203), usually exhibit a superparamagnetic property as their size goes smaller than 20 nm, which are often denoted as superparamagnetic iron oxide nanoparticles (SPIONs) and utilized for drug delivery, diagnosis, therapy, and etc. This review article gives a brief introduction on magnetic iron oxide nanoparticles in terms of their fundamentals of magnetism, magnetic resonance imaging (MRI), and drug delivery, as well as the synthesis approaches, surface coating, and application examples from recent key literatures. Because the quality and surface chemistry play important roles in biomedical applications, our review focuses on the synthesis approaches and surface modifications of iron oxide nanopar- ticles. We aim to provide a detailed introduction to readers who are new to this field, helping them to choose suitable synthesis methods and to optimize the surface chemistry of iron oxide nanoparticles for their interests.
基金Funded by the Project of Shandong Province Higher Educational Science and Technology Program(No.J09LC13)the Promotive Research Fund for Excellent Young and Middle-Aged Scientists of the Shandong Province(No.BS2010CL018)
文摘The hybrid particles composed of hydroxyapatite (HAp) and ferrite ( γ-Fe203) were synthesized by two-step precipitation method. The effect of reaction temperature on the morphology of the hybrids was also studied. The resultant hybrids were characterized by transmission electron microscopy (TEM) and X-ray diffraction analysis(XRD). It was found that γ-Fe203 nanoparticles dispersed within the HAp matrix and these hybrids had a feather-like or spherical morphology when synthesized at 90 ℃ or room temperature, respectively. The magnetic properties of the hybrid showed good superparamagnetic feature, and they could be controlled by the external magnetic field.