以金属钴盐、铁盐及柠檬酸为原料,采用有机凝胶-热分解法成功制备了尖晶石型的CoFe2O4纤维.通过红外光谱(FTIR)、X射线衍射(XRD)、热重-差热分析(TG-DSC)以及扫描电镜(SEM)等分析手段对凝胶的结构、组成、热分解过程以及热处理产物的形貌进行了表征,并分析了影响凝胶可纺性以及纤维产生缺陷的各种因素.结果表明:在pH值为5.5左右的溶液中金属离子与柠檬酸反应形成具有线性分子结构的[(C6H6O7)4CoFe2]n,由这些线性分子所组成的凝胶显示出良好的可纺性.所制备的尖晶石型CoFe2O4纤维由40～50 nm大小的晶粒组成,纤维直径可小于1 μm,长径比达1×106.通过振动样品磁强计(VSM)测得这种尖晶石型CoFe2O4纤维的饱和磁化强度和矫顽力分别为81.97 A·m2/kg和1041.47×79.6 A/m.
Functional spinel ferrite fibers are attractive for high-tech applications. The spinel CoFe2O4 fibres have been prepared by the organic gel-thermal decomposition process from starting materials of Co, Fe nitrate salts and citric acid.The gel spinning performance was a major factor for preparation of uniform gel fibrous precursors. It was related to the citrate-metal complex structure, and linear-type structural molecule [(C6H6O7)4CoFe2]n for the gel precursor was formed during the complexation reaction between the citric acid and metal ions at pH 5.5. As a result, the gel composed of these linear-type molecules exhibited a good spinning performance. The composition, structure of the gel precursors and products derived from thermal decomposition of these precursors were characterized by FTIR, XRD and SEM. The thermal decomposition process of the gel precursors was investigated by TG-DSC. The prepared spinel CoFe2O4 fibres having grain sizes of 40～50 nm possess the diameters of about 1μm, spect ratios up to 1×106 (length/diameter), a saturation
参考文献
| [1] | Thang Pham D;Guus Rijnders;Dave Blank H A .[J].Journal of Magnetism and Magnetic Materials,2005,295:251. |
| [2] | Yangkyu Ahn;Eun Jung Choi;Sehun Kim.[J].Materials Letters,2001(50):47. |
| [3] | Hale D K.[J].Journal of Materials Science,1976(11):2105. |
| [4] | Goldberg Harris A .[P].US 4725490,1988. |
| [5] | Pullar R C;Taylor M D;Bhattacharya A K .[J].Journal of Materials Science,1997,32:349. |
| [6] | Tsai M T .[J].Journal of the European Ceramic Society,2003,23:1283. |
| [7] | Pullar R C;Appleton S G;Bhattacharya A K .[J].Journal of Magnetism and Magnetic Materials,1998,186:326. |
| [8] | Panda R N;Shih J C;Chin T S .[J].Journal of Magnetism and Magnetic Materials,2003,257:79. |
| [9] | 沈湘黔,景茂祥,王涛平,曹凯.有机凝胶-热还原法制备超细金属镍、铁纤维[J].稀有金属材料与工程,2006(06):945-949. |
| [10] | 张春野,沈湘黔,景茂祥,曹凯.有机凝胶-热分解法制备MgO,Al2O3,MgAl2O4微细纤维[J].稀有金属材料与工程,2006(09):1470-1474. |
| [11] | Zhang Haijun;Jia Xiaolin;Yan Yongjie;Liu Zhanjie;Yang Daoyuan;Li Zhenzhen .The effect of the concentration of citric acid and pH values on the preparation of MgAl_2O_4 ultrafine powder by citrate sol-gel process[J].Materials Research Bulletin: An International Journal Reporting Research on Crystal Growth and Materials Preparation and Characterization,2004(6):839-850. |
| [12] | Nakamoto Huang;Deru K;Wang Renqing.Infrared and Raman Spectra of Inorganic and Coordination Compounds[M].北京:化学工业出版社,1986:231. |
| [13] | Strathmann Timothy J;Myneni Satish C B .[J].Geochimica et Cosmochimica Acta,2004,68(17):3441. |
| [14] | Sun Shiyun;Fang Yulong;Fang Yikun et al.[J].Magnetic Material and Devices,2004,35(04):21. |
| [15] | Wu K H;Yu C H;Chang Y C et al.[J].Journal of Solid State Chemistry,2004,177:4119. |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%