Preparation, optical and electrical properties of PTCDA nanostructures

Film, nanorods (NRs), nanowires (NWs), and nanoparticles (NPs) of perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA) were prepared by organic molecular beam deposition (OMBD) on porous anodic alumina oxide (AAO) at different substrate temperatures (Ts). Scanning electron microscopy (SEM) study showed that the morphologies of the nanostructures (NS) formed on AAO strongly depend on the Ts. The absorption spectra of different PTCDA NS present strong absorbance in the wavelength range of 400-600 nm, and the photoluminescence (PL) spectra show a blue shift as Ts increases. The current versus voltage (I-V) characteristic illustrates that the electrical conductivity of the single-crystal NW is about 3 ± 0.1 S m(-1), which is much higher than the conductivity of PTCDA film reported previously.