In this work, an inverted device was fabricated using titania (TiO 2 ) as the electron collecting layer (ECL) and sulfonated poly(diphenylamine) (SPDPA) as the hole collecting layer (HCL). Smooth TiO 2 film with good electron collecting ability was easily formed using the spin-coating process. The power conversion efficiency (PCE) was 3.91%, the same as that of a conventional device. This inverted device is ascertained to maintain 2.82% PCE after 400 h of air-storage. Because of the appropriate work functions of ECL and HCL, the interfaces at the active layer have the ohmic contacts those approach the ideal value of open circuit voltage. SPDPA helps improve the interfacial dipole effect between the active layer and the metal, as verified by in-situ ultraviolet photoelectron spectroscopic data.

Spin‐casting or thermal evaporation in vacuum of a salt‐free, neutral, organic‐oxide ultra‐thin film as a buffer layer with an aluminum (Al) cathode has become an alternative approach for fabricating high‐performance organic and polymer light‐emitting diodes (O/PLEDs). [Guo et al., Appl. Phys. Lett. 2006, 88, 113501 and Appl. Phys. Lett. 2006, 89, 053507] The electroluminescence efficiency of phenyl‐substituted poly(para‐phenylene vinylene) copolymer‐based PLEDs is 0.16 cd A−1 when Al is used as the device cathode, but is approximately two orders of magnitude higher, 14.53 cd A−1, when an organic oxide/Al composite cathode is used. The polymer/metal junction in PLEDs with and without depositing an ultra‐thin organic oxide interlayer is studied by X‐ray photoelectron spectroscopy. Experimental results indicate that the deposition of an Al electrode causes the oxidation at the surface of the light‐emissive polymer layer. Introducing an organic‐oxide cathode buffer layer suppresses the oxidation and the diffusion of the Al atoms into the functional polymer layer. The formation of a carbide‐like (negative carbon) thin layer, which accompanies interfacial interactions, is critical to the injection of electrons through the Al cathode. The balanced charge injection is responsible for the substantially improved device performance. This process is specific to the organic oxide/Al interface, as revealed by a comparison with similar device configurations that have Ag as the electrode, in which no significant interaction in the interface is observed.

Blending 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ), a high electron affinity organic molecule, with N,N′-bis-(1-naphyl)-N,N′-diphenyl-1,1′-biphenyl′-4,4′-diamine (NPB) creates the charge-transfer-complex molecules and modulates the magnetoconductance (MC) responses of devices by an applied electrical bias. A negative MC response (−0.60%) is observed for the device made of NPB:F4-TCNQ(30%) film as the active layer, which has a distinct characteristic to negligible MC responses in pristine NPB- and F4-TCNQ-based devices. We attribute the MC responses to the magnetic-field-dependent transport of injected charge carriers through charge-transfer-complex molecules in the NPB:F4-TCNQ system, which are varied with the F4-TCNQ blending concentrations and the injection of minority charge carriers. Results of this study demonstrate a turning point of MC responses at the bias voltage near the threshold of the bipolar injection.

Oncocytic carcinoma arising in the submandibular gland is an extremely rare tumor and only 11 cases have been reported previously. We report on a 51-year-old man with a previously benign oncocytoma in the submandibular gland that transformed from a benign morphology to malignant cellular atypia and mitosis. To our knowledge, the current report is the first published case of a malignant transformation from benign oncocytoma to oncocytic carcinoma of the submandibular gland. The proliferative activity of the tumor cells was evaluated immunohistochemically using antibodies against Ki-67.

This study elucidates the magnetoconductance (MC) response of polymer diodes, which can be modulated by photoillumination, varying the composition of the active layer and applying electrical bias. Under illumination, the short-circuit current of polymer diodes with active layers of regioregular poly(3-hexylthiophene) (P3HT) exhibits an MC response of approximately −4.0% in a magnetic field B=1000mT at room temperature. The MC response drastically reverses from negative to positive (−23.0% to 2.0%) as the electrical bias is increased from nearly below to above the open-circuit voltage. However, it is quenched (<0.1%) when the illumination is turned off or an electron acceptor material, [6,6]-phenyl C61-butyric acid methyl ester, is blended with P3HT as the active layer, suggesting that, in nature, the MC response is associated with the illumination and excitonic states. The annihilation of triplet excitons probably dominates the negative MC response.