[en] It is well known that multi-walled carbon nanotubes (MWCNTs) are an excellent nanomaterial. In this paper, the nanocomposite ultra-thin films were fabricated consisting of MWCNTs and poly (3,4-ethylene dioxy thiophene-poly(styrene sulfonate) (PEDOT-PSS) for organic light-emitting diode (OLED). The field-emission scanning electron microscopy (FESEM) images of MWCNTs thin films show that the diameter of MWCNTs are 10–30 nm and their length is 300–500 nm. Electrical and optical properties of the films are investigated and the sheet resistance can reach minimum value at 36.5 Ω sq⁻¹ and the transparency of the film is about 80%. The current density–voltage (J–V) characteristics of the devices were also studied. (paper)

[en] The energy transfer in a blend of conducting polymers, poly[9-vinylcarbarzole] (PVK) and poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV), was investigated. Energy transfer from PVK to MEH-PPV leads to enhanced emission of MEH-PPV. Photoluminescence (PL) of the nanocomposite of TiO₂ and the blended polymer films was enhanced as the relative content of TiO₂ was increased, and, in particular, the most improved PL was observed for the optimal ratio of TiO₂ and these films emitted green light. These results provide further insight into the photophysics of conjugated polymers and the improvement of the current–voltage (I–V) characteristics of the devices based on blended conducting polymer systems

[en] We have investigated the enhancement absorption light and luminescence properties of the blend conducting polymers using poly(N-vinylcarbazole) and poly(N-hexylthiophene). The optimized material showed a broad absorption in the region of ultra violet to near infra-red and the better of luminescence ability than the pristine conducting polymers. The remarkable improvements in photoluminescence of the blends provide useful information to the application of this material in fabrication of optical-electronic devices. (author)

[en] The enhancement of light absorption and photoluminescence quenching properties of the bulk heterojunction systems which were fabricated using poly(N-vinylcarbazole) (PVK);poly(N-hexylthiophene) (P3HT) and fullerene derivative 1-(3-methoxycarbonyl) propyl-1-phenyl-[6,6] C61 (PCBM) were investigated. The optimized material showed a broad absorption in the region from ultra violet to near infra-red and the photoluminescence quenching higher than 90%.The obtained results provide further insight into photophysics of the heterojunction system and device performance improvement by using this system as an active layer. (author)

[en] By embedding a thin ZnO layer sandwiched between the hole transport and photoactive layers, organic solar cells (OSC) based on poly(3-hexylthiophene) (P3HT) were prepared by spincoating. UV–vis spectra of the composite films showed that ZnO exhibited a suitable buffer layer that could block holes movement throughout the heterojunction of ITO/ZnO. The enhancement in the fill factor (FF) of the buffer-OSC (BOSC) is attributed to the presence of nanoheterojunctions of ZnO/PCBM and ZnO/ITO. For the normal temperature, the increase of the open-circuit potential and short-circuit current resulted in an overall increase of the energy conversion efficiency. Comparing to OSCs without buffer layer (WOSC), the laminar structure of ITO/ZnO/P3HT/PCBM/Li/Al cells possess a much larger photovoltaic energy conversion efficiency, namely 2.12% (for BOSC) compared to 1.75% (for WOSC). (paper)