Semiconductor-Insulator (Nano-)Couples with Tunable Properties Obtained from Asymmetric Modification of Janus Nanoparticles.

Coupling a semiconductor with an electrical insulator in a single amphiphilic nanoparticle could open new pathways for manufacturing and assembling organic electronic devices. Here, a poly(3,4-ethylenedioxythiophene)/polyaniline (PEDOT/PANI) bilayer is confined on the surface of one lobe of snowman-type Janus nanoparticles (JNPs), such that one lobe is semiconducting and the other is electrically insulating. The PEDOT/PANI bilayer is constructed in two synthesis steps, by asymmetric modification of the JNPs with PANI followed by PEDOT. The addition of the PEDOT layer onto the PANI-modified JNPs leads to an enhancement in the conductivity of up to 2 orders of magnitude. Further, we demonstrate that JNPs are very versatile supports for semiconducting polymers because by tuning their size and geometry the overall conductivity of the JNP powders can be modulated within several orders of magnitude.