Synthesis and high-temperature performance of Ti substituted α-Ni(OH)2
(Department of Chemical Engineering, Tsinghua University, Beijing 100084, China)
Abstract: Ti substituted α-Ni(OH)2(c=2.121nm, a=0.307nm) with perfect high-temperature performance was prepared by the co-precipitation method. The effects of Ti addition on the structure and the electrochemical properties were investigated. The results indicate that the substitution of Ti for Ni leads to the conversion of β-Ni(OH)2 to α-Ni(OH)2 and the increase of the inter layer distance along c-axis from 0.464nm to 0.707nm. Infrared study reveals that more anions(SO2-4 and CO2-3 ions) and H2O exist in the Ti substituted α-Ni(OH)2. The discharge capacity of the Ti substituted α-Ni(OH)2 is 210mA•h/g at 20℃ and reaches up to 270mA•h/g at 80℃ owing to the inhibition of the oxygen evolution at high temperature.
Key words: α-Ni(OH)2; titanium; structure; high temperature performance