Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Monodisperse a-Fe2O3 Mesoporous Microspheres: One-Step NaCl-Assisted Microwave-Solvothermal | Cao and Zhu Nanoscale Res Lett 2011 6 1 http content 6 1 1 o Nanoscale Research Letters a SpringerOpen Journal NANO EXPRESS Open Access Monodisperse a-Fe2O3 Mesoporous Microspheres One-Step NaCl-Assisted Microwave-Solvothermal Preparation Size Control and Photocatalytic Property Shao-Wen Cao Ying-Jie Zhu Abstract A simple one-step NaCl-assisted microwave-solvothermal method has been developed for the preparation of monodisperse a-Fe2O3 mesoporous microspheres. In this approach Fe NO3 3 9H2O is used as the iron source and polyvinylpyrrolidone PVP acts as a surfactant in the presence of NaCl in mixed solvents of H2O and ethanol. Under the present experimental conditions monodisperse a-Fe2O3 mesoporous microspheres can form via oriented attachment of a-Fe2O3 nanocrystals. One of the advantages of this method is that the size of a-Fe2O3 mesoporous microspheres can be adjusted in the range from ca. 170 to ca. 260 nm by changing the experimental parameters. High photocatalytic activities in the degradation of salicylic acid are observed for a-Fe2O3 mesoporous microspheres with different specific surface areas. Introduction The fabrication of mesoporous materials of transition metal oxides has attracted more and more attention in recent years for their unique catalytic electrochemical magnetic and adsorptive properties 1-4 . Among them a-Fe2O3 mesoporous materials are of particular interest because a-Fe2O3 is widely used in catalysis 5 photoelectrodes 6 sensors 7 the anode material for Li-ion batteries 8 and so on. As an important n-type semiconductor a-Fe2O3 is also used as a photocatalyst 9 10 especially in the degradation of salicylic acid 11-13 . Salicylic acid is a complexing agent that forms stable complexes with iron ions and it is one of pollutants in waste effluent 14 . Mesoporous structures will benefit the photocatalytic activity of a-Fe2O3 due to the high specific surface area and the redox activity of the surfaces and nanopores. .
