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We demonstrate that the open-circuit voltage (VOC) of organic photovoltaic (OPV) devices composed of rubrene and C60 can be considerably different when the anode and active layer are changed. Two types of anodes and active layers were compared. In plasma-treated indium-tin-oxide (ITO) OPV devices, the parameter VOC exhibits an improvement from 0.68 V to 0.76 V when the device structure is varied from a bilayer to a mixed structure. However, in the OPV devices that use ITO/MoO3 as the anode, a similar VOC is observed regardless of the device structure. A series of temperature-dependent measurements are conducted to investigate these results. The calculation of barrier height at the rubrene/C60 (or rubrene:C60) interface yields the prediction of VOC, suggesting that an excess energetic loss occurs in the mixed structures. The electroluminescent (EL) spectra of these devices show that the mixed structure can completely quench the EL of rubrene single layer. A broad band of the charge transfer (CT) emission is observed clearly. A temperature-dependent measurement for the extracting injection barrier is conducted and shows that the mixed structure is favorable for the hole current injection. The CT properties are obtained using the external quantum efficiency and EL spectra of the OPV devices. We find that the nonradiative recombination loss is highly correlated with the injected current; the lower the injection barrier induced the less the nonradiative recombination loss. Therefore, the parameter VOC can be improved when the injected current is increased.

This work studies the open-circuit voltage (VOC) of planar and bulk heterojunction organic photovoltaic (OPV) devices by means of electroluminescent (EL) technique to resolve the charge transfer (CT) states between donor and acceptor. The OPV devices containing a small part of bulk heterojunction increases the VOC as a result of the enhanced CT process as compared with a complete planar structure. Red shift of the CT charge transfer was observed by increasing the bulk volume, which indicates the increased degree of interaction between both molecules and excitons. By characterizing the EL spectra of OPV devices and relating them to the CT absorption, the interfacial property between the donor and acceptor is shown to be crucial for determining the VOC in small-molecule OPV devices. Detailed analysis of the energetic loss was also used to interpret the VOC under the effect of CT states.

A planar heterojunction organic solar cell (OSC) with high internal quantum efficiency (IQE=95.6% at 590 nm) was demonstrated based on boron subphthalocyanine chloride (SubPc) and C 60 as the electron donor and acceptor materials. A thin layer of N,N-dicarbazolyl-3,5-benzene (mCP), acting as an electron and exciton blocking layer, was inserted between the ITO anode and the SubPc layer to prevent leakage current and exciton quenching. In the optimized device, a mCP thickness of 3 nm was thick enough to block the excitons (as suggested by a high IQE and longer-lived photoluminescence), resulting in an open circuit voltage of 1.09 V, a short circuit current of 7.87 mA/cm 2 , a fill factor of 59, and a power conversion efficiency of 5.08%. Increasing the mCP thickness resulted in increased serial resistance and SubPc crystallization that reduced the fill factor, V OC , and J SC . Due to the narrow absorption band of SubPC (71 nm at the full-width-at-half-maximum), this high performance (both in peak IQE and V OC ) device has the potential to be used as a subcell in a spectral splitting solar cell module.

We present an electrical characterization of the organic field-effect transistor with purified and non-purified pentacene by using in situ and real time measurements. The field-effect phenomenon was observed at the thickness of 1.5 nm (approximately one monolayer of pentacene) for purified pentacene, as compared to 3.0 nm for the non-purified counterpart. Moreover, the hole mobility is improved from 0.13 to 0.23 cm2/V s after the sublimation process to purify the pentacene. With atomic force microscopic measurements, the purified pentacene thin film exhibits a larger grain size and film coverage, resulting in better crystallinity of the thin film structure due to the absence of the impurities. This is further confirmed by X-ray diffraction patterns, which show higher intensities for the purified pentacene.

In this paper, we demonstrate the effects of donor deposition rate on an organic photovoltaic device using bis(4-(N-(1-naphthyl)phenylamino)phenyl)fumaronitrile (NPAFN) as the donor. When the deposition rate of NPAFN increased from 0.03 to 0.5 nm/s, the performance of the device improved from 1.98% to 2.3% due to significant enhancement in the open-circuit voltage (VOC) from 0.81 to 0.97 V. With the aid of diode equation fitting, the improved VOC is attributed to the low saturation current caused by weak molecular interaction during the deposition of NPAFN at a high deposition rate. In order to understand the detail of the molecular interaction, the morphological property of NPAFN thin film with various deposition rates is investigated using atomic force microscopic images, which show the emergence of pinholes at low deposition rates as a result of strong molecular aggregation. Moreover, the weak molecular interaction is found to contribute to the low carrier mobility in NPAFN from the calculation of space charge limited current, leading to the considerably increased bulk resistance and reduced fill factor as the deposition rate increases. The detailed electrical properties of the NPAFN device were analyzed using impedance spectra.

Buckminsterfullerene, C60-based planar heterojunction (PHJ) organic photovoltaics (OPVs) have been created using a short wavelength absorption (λmax = 490 nm) electron-donating bis(naphthylphenylaminophenyl)fumaronitrile (NPAFN). NPAFN exhibits a hole mobility greater than 0.07 cm2 V−1 s−1 as determined by its field-effect transistor. It can be attributed to such hole mobility that enables a thin layer (

High efficiency and high open-circuit voltage ( V OC ) ITO/boron subphthalocyanine chloride (SubPc)/C 60 /bathocuproine/Al organic photovoltaic devices were fabricated in this study. Molecular packing was adjusted by controlling the deposition rate of SubPc, thus influencing the energy level of SubPc, which not only increased the energy level difference from the LUMO level of C 60 to the HOMO level of SubPc, but also reduced the energy barrier between the ITO/SubPc interface and diminished the accumulation and recombination of holes in SubPc, resulting in considerable improvement in both the V OC (1.02 V) and fill factor (65.37%) of the device, and a 3.96% final efficiency of the device.

Sailfish (Istiophorus platypterus) are of substantial economic importance to Taiwan because of their seasonal abundance (April to October, with a peak from May to July) off the island's eastern coast. They are harvested by drift gill nets, set nets, harpoons, and as incidental bycatch by inshore longline fisheries. Although the biology of sailfish has been investigated in eastern Taiwan, there is a paucity of data on movement patterns. Pop-up satellite archival tags (PSATs) were used to study the vertical and horizontal movements of three sailfish in 2008. The fish were tagged near the southeastern coast of Taiwan and linear displacements ranged from 1050 to 1400 km (~ 40 km day− 1) from deployment to pop-up locations and all movements were confined to the East China Sea. Sailfish spent 88% of their time in the upper uniform mixed layer above 50 m, but made more extensive vertical movements during the nighttime ( x ¯ = 60.61 m ± 48.24 SD) than daytime ( x ¯ = 35.21 m ± 35.37 SD). Depths and ambient water temperatures visited ranged from 0 to 214 m and 30.0° to 17.8 °C, respectively. However in all cases, the depth distribution appeared primarily limited by an 8 °C change in water temperature. Diel diving patterns also suggested basking behavior. Sailfish behavior makes them particularly vulnerable to surface fishing gears.

The carcinogenic process initiated by nongenotoxic carcinogens involves modulation of gene expression. Nickel compounds have low mutagenic activity, but are highly carcinogenic. In vitro both mouse and human cells can be efficiently transformed by soluble and insoluble nickel compounds to anchorage-independent growth. Because previous studies have shown that carcinogenic nickel compounds silence genes by inhibiting histone acetylation and enhancing DNA methylation, we investigated the effect of enhancing histone acetylation on cell transformation. The exposure of nickel-transformed cells to the histone deacetylase inhibitor trichostatin A (TSA) resulted in the appearance of significant number of revertants measured by their inability to grow in soft agar. Using the Affymetrix GeneChip we found that the level of expression of a significant number of genes was changed (suppressed or upregulated) in nickel-transformed clones but returned to a normal level in revertants obtained following TSA treatment. Moreover, we found that treatment of cells with TSA inhibited the ability of nickel to transform mouse PW cells to anchorage-independent growth. Treatment with TSA also inhibited the ability of nickel to transform human HOS cells, although to a lesser extent. In contrast, treatment with TSA was not able to revert established cancer cell lines as readily as the nickel-transformed cells. These data indicated that modulation of gene expression is important for nickel-induced transformation.

Erratum to “Chloroboron subphthalocyanine/C60 planar heterojunction organic solar cell with N,N-dicarbazolyl-3,5-benzene blocking layer” [Sol. Energy Mater. Sol. Cells 122 (2014) 264–270] Chi-Feng Lin , Valerie Nichols , Yung-Chih Cheng , Christopher J. Bardeen , Mau-Kuo Wei , Shun-Wei Liu , Chih-Chien Lee , Wei-Cheng Su , Tien-Lung Chiu , Hsieh-Cheng Han , Li-Chyong Chen , Chin-Ti Chen , Jiun-Haw Lee j,n