Organic Light Emitting Devices Fabricated from Semiconducting Nanospheres

ABSTRACTOrganic light emitting diodes (OLEDs) have been fabricated from organic semiconducting polymer nanospheres (SPNs) which have been deposited from aqueous dispersions. The active layer of the devices consists of a single, homogeneous layer of light emitting SPNs, as verified by optical, interferometric and surface probe measurements. Different batches of SPNs with different SPN diameters have been tested (69nm, 95nm, 126nm and 150 nm). All SPN-based OLEDs exhibit a light emission onset corresponding to the SPN energy gap (ca. 2.7 eV for m-LPPP, a semiconducting para-phenylene ladder polymer). The low onset is attributed to field enhanced injection of charge carriers at the aluminum cathode due to the formation of stalactite-type nanostructures. A detailed comparison of the SPN-based and bulk semiconducting polymer films reveals no differences in the basic optoelectronic properties.</jats:p

Organic light-emitting devices fabricated from semiconducting nanospheres

The successful fabrication of organic light emitting diodes (OLEDs) utilizing organic semiconducting polymer nanospheres was reported. The devices consist of a homogeneous single layer of nanosized semiconducting conjugated polymer nanospheres (SPNs) and reveal improved opto-electronic characteristics compared with "traditionally" fabricated OLEDs for which the active layer was cast from a solution of the conjugated polymer in an organic solvent. Optical spectroscopy have evidenced that conjugated polymers can be converted into aqueous SPN dispersions without generation of electronic defects; the SPNs display the photophysical properties of the bulk polymer

Materials for polymer electronics applications semiconducting polymer thin films and nanoparticles

The paper presents two different approaches to nanostructured semiconducting polymer materials: (i) the generation of aqueous semiconducting polymer dispersions (semiconducting polymer nanospheres SPNs) and their processing into dense films and layers, and (ii) the synthesis of novel semiconducting polyfluorene-block-polyaniline (PF-b-PANI) block copolymers composed of conjugated blocks of different redox potentials which form nanosized morphologies in the solid stat