tailieunhanh - Báo cáo hóa học: "Synthesis, structure and magnetic properties of b-MnO2 nanorods"

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: Synthesis, structure and magnetic properties of b-MnO2 nanorods | Nanoscale Res Lett 2007 2 81-86 DOI s11671-006-9034-4 NANO EXPRESS Synthesis structure and magnetic properties of -MnO2 nanorods Hae Jin Kim Jin Bae Lee Young-Min Kim Myung-Hwa Jung Z. JagliCiC P. Umek J. Dolinsek Published online 11 January 2007 to the authors 2007 Abstract We present synthesis structure and magnetic properties of structurally well-ordered single-crystalline b-MnO2 nanorods of 50-100 nm diameter and several m length. Thorough structural characterization shows that the basic b-MnO2 material is covered by a thin surface layer nm of a-Mn2O3 phase with a reduced Mn valence that adds its own magnetic signal to the total magnetization of the b-MnO2 nanorods. The relatively complicated temperature-dependent magnetism of the nanorods can be explained in terms of a superposition of bulk magnetic properties of spatially segregated b-MnO2 and a-Mn2O3 constituent phases and the soft ferromagnetism of the thin interface layer between these two phases. Keywords Self-assembled nanorods Manganese oxides Nanoscale magnetism H. J. Kim J. B. Lee Energy Nano Material Team Korea Basic Science Institute Daejeon 305-806 Korea Y. -M. Kim Division of Electron Microscopic Research Korea Basic Science Institute Daejeon 305-806 Korea . Jung Quantum Material Research Team Korea Basic Science Institute Daejeon 305-806 Korea Z. Jaglicic Institute of Mathematics Physics and Mechanics Jadranska 19 Ljubljana 1000 Slovenia P. Umek J. Dolinsek El J. Stefan Institute University of Ljubljana Jamova 39 Ljubljana 1000 Slovenia e-mail Introduction The one-dimensional 1D nanostructures in the form of single-crystalline nanorods and nanowires have attracted considerable interest because of their fascinating application as interconnects and building blocks in the nanoscale electronic optoelectronic and spin-tronic devices 1-3 . Self-assembled quasi-1D nanorods and nanowires of typically several 10 nm in diameter and several m in length are the .