| 摘要 |
<p>A method for the synthesis of nanocomposites is provided. The method comprises the steps of mixing carbon nanotubes with a urea solution to form urea/carbon nanotube composites (first step), mixing the urea/carbon nanotube composites with a solution of a metal oxide or hydroxide precursor to prepare a precursor solution (second step), and hydrolyzing the urea in the precursor solution to form a metal oxide or hydroxide coating on the carbon nanotubes (third step). Further provided are nanocomposites synthesized by the method. In the nanocomposites, a metal oxide or hydroxide is coated to a uniform thickness in the nanometer range on porous carbon nanotubes. Advantageously, the thickness of the coating can be easily regulated by controlling the urea content of urea/carbon nanotube composites as precursors. In addition, the nanocomposites are nanometer-sized powders and have high electrical conductivity and large specific surface area. Therefore, the nanocomposites are useful as electrode active materials for electrochemical capacitors, including pseudo capacitors and electrochemical double layer capacitors, lithium secondary batteries, and polymer batteries. Further provided is a capacitor comprising the nanocomposites.</p> |
