Ammonium lithocholate nanotubes: stability and copper metallization.

Ammonium lithocholate nanotubes (NHLC) have been prepared in alkaline ammonia solutions and exhibited remarkable monodisperse cross-sectional dimensions (external diameter = 52 nm) as shown by cryo-transmission electron microscopy measurements. A classical electroless metallic replication method was used with a single poly(ethylene-imine) PEI layer coating the negatively charged NHLC nanotubes. Short copper rods (external diameter ∼ 80 nm) were observed by scanning electron microscopy that corresponded to the original organic templates.