Synthesis and behavior ofAl-stabilized α-Ni（OH）2

Nano-fibrous Al-stabilized α-Ni（OH）2 was synthesized by the urea thermal decomposition method. The grain morphology, crystal structure, thermal stability, chemical composition and electrochemical performance of the Al-stabilized α-Ni（OH）2 were investigated. It is found that the urea thermal decomposition is an appropriate way to precipitate the Al-stabilized α-Ni（OH）2 with excellent performance. The fiber cluster TEM pattern shows that the synthesized α-Ni（OH）2 powder is composed of agglomerates of much smaller primary particles. The stabilized α-Ni（OH）2 powder with a 7.67 A, c-axis distance and low thermal stabilities is obtained. The FTIR spectrum shows that the materials contain absorbed water molecules, and intercalated CO3^2- and SO4^2- anions. The experimental α-Ni（OH）2 electrode exhibits excellent electrochemical redox reversibility, high special capacity, good rate discharging performance and perfect cyclic stability. Moreover, the synthesized α-Ni（OH）2 electrode also shows high discharge capacity and cyclic stability at high temperature. The electrode specific capacity remains 290 mA.h/g at 60 ℃, which is only 15 mA.h/g lower than its ambient value, and the capacity loss is 0.9 mA.h/g per charge-discharge cycle.