Magnetic Sponge Prepared with an Alkanedithiol-Bridged Network of Nanomagnets

详细信息    查看全文

• 作者：Yoshikazu Ito ; Akira Miyazaki ; Kazuyuki Takai ; Vajiravelu Sivamurugan ; Takashi Maeno ; Takeshi Kadono ; Masaaki Kitano ; Yoshihiro Ogawa ; Naotake Nakamura ; Michikazu Hara ; Suresh Valiyaveettil ; Toshiaki Enoki
• 刊名：Journal of the American Chemical Society
• 出版年：2011
• 出版时间：August 3, 2011
• 年：2011
• 卷：133
• 期：30
• 页码：11470-11473
• 全文大小：818K
• 年卷期：v.133,no.30(August 3, 2011)
• ISSN：1520-5126

文摘

The magnetic dipole鈥揹ipole interaction between nanomagnets having huge magnetic moments can have a strength comparable to that of the van der Waals interaction between them, and it can be manipulated by applying an external magnetic field of conventional strength. Therefore, the cooperation between the dipole鈥揹ipole interaction and the applied magnetic field allows the magnetic moments of nanomagnets to be aligned and organized in an ordered manner. In this work, a network of magnetic nanoparticles connected with flexible long-alkyl-chain linkers was designed to develop a 鈥渕agnetic sponge鈥?capable of absorbing and desorbing guest molecules with changes in the applied magnetic field. The magnetization of the sponge with long-alkyl-chain bridges (30 C atoms) exhibited a 500% increase after cooling in the presence of an applied field of 7 T relative to that in the absence of a magnetic field. Cooling in a magnetic field leads to anisotropic stretching in the sponge due to reorganization of the nanomagnets along the applied field, in contrast to the isotropic organization under zero-field conditions. Such magnetic-responsive organization and reorganization of the magnetic particle network significantly influences the gas absorption capacity of the nanopores inside the material. The absorption and desorption of guests in an applied magnetic field at low temperature can be regarded as a fascinating 鈥渂reathing feature鈥?of our magnetic sponge.