Ahmed Jahangeer, Ahmad Tokeer, Ramanujachary Kandalam V, Lofland Samuel E, Ganguli Ashok K
Department of Chemistry, Indian Institute of Technology, Hauz Khas, New Delhi 110016, India.
J Colloid Interface Sci. 2008 May 15;321(2):434-41. doi: 10.1016/j.jcis.2008.01.052. Epub 2008 Mar 10.
Rod-shaped nanostructures of cobalt oxalate dihydrate were synthesized at room temperature by the microemulsion (reverse micellar) route. These rods are highly uniform in length and can be modified with temperature (from approximately 6.5 microm at 50 degrees C to approximately 2.5 microm at 150 degrees C) while keeping the diameter nearly constant (200-250 nm). Thermal decomposition of these rods in a controlled atmosphere (air and H(2)) leads to nanoparticles of Co(3)O(4) and Co, respectively, while in a helium atmosphere a mixture of Co and CoO nanoparticles is obtained. Co(3)O(4) nanoparticles (approximately 35 nm) were slightly agglomerated, while Co nanoparticles were monodispersed and highly uniform (approximately 25 nm). The oxalate rods and Co(3)O(4) nanoparticles show an antiferromagnetic ordering at 54 and 35 K, respectively.
通过微乳液（反胶束）法在室温下合成了二水合草酸钴的棒状纳米结构。这些棒的长度高度均匀，并且可以随温度变化（从50℃时约6.5微米到150℃时约2.5微米），同时直径几乎保持恒定（200 - 250纳米）。在可控气氛（空气和H₂）中对这些棒进行热分解，分别得到Co₃O₄和Co的纳米颗粒，而在氦气氛中则得到Co和CoO纳米颗粒的混合物。Co₃O₄纳米颗粒（约35纳米）略有团聚，而Co纳米颗粒是单分散且高度均匀的（约25纳米）。草酸钴棒和Co₃O₄纳米颗粒分别在54K和35K时呈现反铁磁有序。
