Structure and Electrochemical Performance of Ni-Al Layered Double Hydroxides Doped with Co and La

Chemical co-precipitation was used to prepare Ni-Al layered double Hydroxides doped with both Co and La and each one of them, respectively. The morphologies, specific surface areas, crystal structures and electrochemical performances of the products were analyzed or tested. Experimental results showed that the sample doped with both Co and La had particle shape approximating to sphere. Its specific surface area reached 132.5 m(2)/g and crystallinity was higher than that of the sample doped with La. Because more H2O molecule, CO32- and NO3- anions were intercalated in the interlayer region, the stability of crystal structure was enhanced. On the other hand, the sample had higher redox reaction reversibility and electrochemical activity, and its average discharge specific capacity attained 311.5 mAh/g at 1C rate when used as cathode active material for MH/Ni battery. The electrode with it exhibited excellent cycle stability and better charge-discharge performance than that with Co doped or La doped sample.