MnFe204 nanoparticles (NPs) with various sizes and tight size-distribution were synthesized by a chemical solution- phase method. The as-synthesized NPs were coated with a silica shell of 4 nm-5 nm in thickness, ena...MnFe204 nanoparticles (NPs) with various sizes and tight size-distribution were synthesized by a chemical solution- phase method. The as-synthesized NPs were coated with a silica shell of 4 nm-5 nm in thickness, enabling the water- solubility and biocompatibility of the NPs. The MnFe204 NPs with a size of less than 18 nm exhibit superparamagnetic behavior with high saturated magnetization. The capacity of the heat production was enhanced by increasing particle sizes and radio frequency (RF) field strengths. MnFe204/SiO2 NPs with 18-nm magnetic cores showed the highest heat- generation ability under an RF field. These MnFe204/SiO2 NPs have great potentiality to cancer treatments, controlled drug releases, and remote controls of single cell functions.展开更多
In the quest for developing a catalyst with as many desired characteristics, a facile synthetic route was designed for the preparation of mesoporous silica coated magnetic nanoparticles(MSMNP) employing a colloid mi...In the quest for developing a catalyst with as many desired characteristics, a facile synthetic route was designed for the preparation of mesoporous silica coated magnetic nanoparticles(MSMNP) employing a colloid mill reactor. The composite particles were characterized by the techniques, such as nitrogen adsorption-desorption isotherms, scanning electron microscopy(SEM), transmission electron microscopy(TEM), X-ray diffraction patterns (XRD), thermo-gravimetric analysis(TGA), Fourier transform infrared spectroscopy(FTIR) and vibrating sample magnetometer(VSM), etc. The analysis showed that the resulted MSMNP composites were composed of silica shell layers with open pores connecting channels and NiFe204 with spinel structure, so the thermal treatment temperature did not show significant effect on pore textural properties, and its specific surface areas were in the range of 443-- 474 m2/g, while pore volume of about 0.8 cm3/g with an average pore size of around 9.5 nm. The composites with super paramagnetic nature were encapsulated entirely with amorphous silica layers contributing to optimum porosity and abundant surface hydroxyl groups.展开更多
文摘MnFe204 nanoparticles (NPs) with various sizes and tight size-distribution were synthesized by a chemical solution- phase method. The as-synthesized NPs were coated with a silica shell of 4 nm-5 nm in thickness, enabling the water- solubility and biocompatibility of the NPs. The MnFe204 NPs with a size of less than 18 nm exhibit superparamagnetic behavior with high saturated magnetization. The capacity of the heat production was enhanced by increasing particle sizes and radio frequency (RF) field strengths. MnFe204/SiO2 NPs with 18-nm magnetic cores showed the highest heat- generation ability under an RF field. These MnFe204/SiO2 NPs have great potentiality to cancer treatments, controlled drug releases, and remote controls of single cell functions.
文摘In the quest for developing a catalyst with as many desired characteristics, a facile synthetic route was designed for the preparation of mesoporous silica coated magnetic nanoparticles(MSMNP) employing a colloid mill reactor. The composite particles were characterized by the techniques, such as nitrogen adsorption-desorption isotherms, scanning electron microscopy(SEM), transmission electron microscopy(TEM), X-ray diffraction patterns (XRD), thermo-gravimetric analysis(TGA), Fourier transform infrared spectroscopy(FTIR) and vibrating sample magnetometer(VSM), etc. The analysis showed that the resulted MSMNP composites were composed of silica shell layers with open pores connecting channels and NiFe204 with spinel structure, so the thermal treatment temperature did not show significant effect on pore textural properties, and its specific surface areas were in the range of 443-- 474 m2/g, while pore volume of about 0.8 cm3/g with an average pore size of around 9.5 nm. The composites with super paramagnetic nature were encapsulated entirely with amorphous silica layers contributing to optimum porosity and abundant surface hydroxyl groups.