Electrodeposition of nonconducting polymers: roles of carbon nanotubes in the process and products.

The self-limiting electrodeposition of nonconducting polymers, such as poly(o-aminophenol) (PoAP), has been continued by the addition of acid treated carbon nanotubes (CNTs) into the aqueous monomer solution without any other supporting electrolyte. Electron microscopy revealed fairly thick (>8 microm) and highly porous nanocomposite films on electrodes, consisting of CNTs which were well interconnected and individually coated with a thin layer (e.g., 30 nm) of the nonconducting polymer. The mechanism behind this approach is explainable by the newly arrived CNTs and those entrapped in the nonconducting polymer matrix providing extra reaction and growth sites, and extended electron pathways, leading to sustained electro-co-deposition of the nonconducting polymer and CNTs into the nanoporous composite films. Promising applications of the PoAP-CNT composite were explored, such as CO2 sensing in water, and energy storage in an unprecedented metal-free supercapattery.