废旧镍氢电池溶胶–凝胶法制备Ni_(0.5)Co_(0.5)Fe_2O_4的研究

Preparation of Ni_(0.5)Co_(0.5)Fe_2O_4 nanocrystals by sol-gel method using spent Ni-MH batteries as resourse materials

以硫酸溶解废旧镍氢电池所得溶液为原料,采用溶胶–凝胶法制备出纳米晶镍钴铁氧体。借助于XRD、TG和VSM对产品的相结构和磁性能进行研究,并进一步探讨制备过程中的影响因素。结果表明,溶胶–凝胶法制备镍钴铁氧体的适宜条件为:柠檬酸与金属离子总量的摩尔比1:1,溶液的pH值7.0,煅烧温度850℃,煅烧时间3 h。该条件下所制得产品的剩余磁化强度为13.635 A.m2/kg,矫顽力为32.5 kA/m,饱和磁化强度为50.713 A.m2/kg。

Nanocrystal Ni-Co ferrites were synthesized by sol-gel method using spent Ni-MH batteries. The structures and magnetic properties of the prepared samples were investigated by XRD, TG and VSM, and the influencing factors in the preparation process were further discussed. The results show that the Ni-Co ferrites can be synthesized successfully by sol-gel method at calcined temperature of 850 ℃ for 3 h when the molar ratio of the citric acid to the total metal ions is 1：1 and the pH value of the solution is 7.0. The remanent magnetization （Mr）, coercivity （He） and saturation magnetization （Ms） of the product prepared under these conditions are 13.635 A·m^2/kg, 32.5 kA/m and 50.713 A·m^2/kg respectively.