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An experimental apparatus for the methane and air mixture explosion with N2/CO2 in a closed vessel was set up. A series of experiments have been performed to analyze the effects of N2/CO2 on explosion strength, limiting oxygen concentration, flammability limits and explosion suppression. Results show that explosion strength decreases with the volume fraction of N2/CO2 in the mixture. Limiting oxygen concentration decreases linearly with the volume fraction of N2 in N2/CO2 mixture. The flammability limits change linearly with the volume fraction of N2/CO2 in the mixture. The higher the volume fraction of CO2 in N2/CO2 mixture, the better the explosion suppression effect is. Based on experimental data, fitted equations and diagrams are made to predict methane flammability limits with N2/CO2 under different volume fraction ratio of N2 and CO2. The research results can be used as a reference for the inerting treatment design of methane explosion protection in process industries.

Organic photovoltaics are under intense development and significant focus has been placed on tuning the donor ionization potential and acceptor electron affinity to optimize open circuit voltage. Here, it is shown that for a series of regioregular-poly(3-hexylthiophene): fullerene bulk heterojunction (BHJ) organic photovoltaic devices with pinned electrodes, integer charge transfer states present in the dark and created as a consequence of Fermi level equilibrium at BHJ have a profound effect on open circuit voltage. The integer charge transfer state formation causes vacuum level misalignment that yields a roughly constant effective donor ionization potential to acceptor electron affinity energy difference at the donor-acceptor interface, even though there is a large variation in electron affinity for the fullerene series. The large variation in open circuit voltage for the corresponding device series instead is found to be a consequence of trap-assisted recombination via integer charge transfer states. Based on the results, novel design rules for optimizing open circuit voltage and performance of organic bulk heterojunction solar cells are proposed. Funding Agencies|Swedish Energy Agency [34142-1]; European Commission [287594]; Academy of Finland [137093]; Swedish Research Council Linnaeus grant LiLi-NFM; Waldemar von Frenckell Foundation; Swedish Cultural Foundation in Finland; Advanced Functional Materials Center at Linkoping University

Preparation of size-tunable ultrathin W18O49 nanowires by an alcohol-assisted solvothermal decomposition of tungstic acid is reported. The synthesis of ultrathin W18O49 nanowires can be achieved at large scale and low cost, while changing the molecular size of the used alcohols can control the nanowire morphology. With increasing the molecular size of the alcohol, the synthesized W18O49 nanowires have smaller diameters and longer lengths. The as-prepared blue W18O49 nanomaterials show a very strong visible light absorption caused by oxygen defects and an aspect ratio-dependent photocatalytic activity on the degradation of pollutant rhodamine B (RhB) under simulated solar light irradiation. It is found that the W18O49 nanowires with highest aspect ratio show the highest activity in the photodegradation of RhB, which could be related to their higher density of oxygen surface defects in combination with a higher adsorption capability of RhB. This new synthetic route of size tunable ultrathin W18O49 nanomaterials will enlarge their potential applications and can be possibly used in the pyrolyzing synthesis of other metal oxide nanomaterials.

The molecular organization of a polar phthalocyanine, titanyl phthalocyanine (TiOPc), on the Ag(110) surface was studied with scanning tunneling microscopy (STM). In addition to the intermolecular hydrogen bonding and electrostatic interactions that guide structure for nonpolar Pc’s, we find evidence for the impact of dipole interactions on layer organization for TiOPc/Ag(110). TiOPc molecules adsorb on Ag(110) with a tilted orientation that contrasts with the flat-lying orientation typically observed for nonpolar phthalocyanines. At the highest TiOPc coverages, the layer consists of neighboring TiOPc molecules with opposing molecular tilts. Close inspection reveals a higher level organization, consisting of “zigzag” TiOPc molecular chains with molecular spacings along the chain that are smaller than the average within the layer. We suggest an explanation for this behavior based on the dipole–dipole interactions within the chain. At reduced coverage, variable densities of molecular vacancies form, dependi...

During the cementing process of natural gas hydrate (NGH) layer, the hydration heat of cement slurry can easily cause decomposition of NGH which leads to cementing risk. A thermal control material of phase change micro-capsule (PCM-1) with paraffin as the core material and urea-formaldehyde resin as the wall material was successfully synthesized, and then a low hydration heat cement slurry was prepared by using PCM-1. The basic performances of PCM-1 were characterized by using DSC, FTIR, SEM and TG, and the results show that the performances meet designed requirements. Then, the PCM-1 was introduced into cement slurry system, and the hydration heat (Q) and hydration temperature rise (Tr) were measured by using the self-developed semi-adiabatic test equipment. As a result, it was confirmed that the Q and the Tr decrease with the increase of PCM-1 content. The Tr of cement slurry CP15% was 25.4 °C, lower than that of cement slurry CB. Meanwhile, compared with cement slurry CB, at 24 and 48 h hydration heat of cement slurry CP15% were decreased by 7.68 × 104 and 7.28 × 104 J, respectively. Therefore, the decomposition of NGH was avoided attribute to the smaller Q of cement slurry, and the cementing operation risk in deep water was reduced.

e14250 Background: Systemic administration of checkpoint inhibitors alone and especially concurrent with intratumoral administration of oncolytic herpes simplex viruses (oHSV) have a major impact on cancer therapy marred by rare failures of healthy organs. Methods: We constructed 3 families of recombinant oHSVs expressing no immunomodulatory genes (T1 series), murine or human IL-12 (T2 series) and murine or human IL-12 and anti-PD-1 antibody (T3 series). We compared the oncolytic effects of a single or multiple intratumoral injection(s) of T1, T2 and T3 series oHSVs. We also compared the effectiveness of intratumoral injection of T3 oHSV with systemic administration of anti PD-1 ab and IL12 alone or in combinations with T1. Results: Insertion of the gene encoding PD-1 Ab significantly augmented the oncolytic activity of oHSV bereft of immunostimulatory genes (T1 series) or expressing IL-12 alone (T2 series). In syngeneic mice the T3 series oHSV expressing murine IL-12 and PD-1 Ab was effective against a variety of murine tumors. Concurrent with enhanced cytolytic activity the T3 oHSV induced the production and significant intratumoral accumulation of IL-12, PD-1 Ab and IFN-γ. Consistent with an earlier report we noted an inverse correlation between the volume of the tumor and the quantity of retained IFN-γ. The most effective oncolytic effect resulted from the administration of T3855 expressing both IL12 and anti PD-1 antibody or T2850 concurrently with intraperitoneal administration of anti PD-1 antibody alone. The least effective were single intraperitoneal administration of IL12 or PD-1 antibody. Intratumoral injection of T3 oHSV was most effective against murine tumors in comparison of either systemic administration of anti PD-1 ab and IL12 or intratumoral injection of T1 in combinations of systemic administration of anti PD-1 ab and IL12. Conclusions: We report the marriage in a single therapeutic agent of three distinct cancer therapies: the targeting of cancer cells by oncolytic viruses, the stimulation of immune system by IL12, and the production of immunotherapeutic antibodies against PD-1. The significant finding reported in this article is that the anti-tumor responses remain concentrated in the tumor environment.

Heterogeneous electron transport (HET) is important in many technologies, including batteries, fuel cells, medical sensors, organic electrochemical synthesis, food analysis, corrosion protection, and thermogalvanic cell. HET takes place at the interface between a solid electrode and a reactant in a liquid electrolyte, and it depends on the type of reactants, electrodes, solvents, and electrolyte. HET has been well studied for metal, semiconductor, metal oxide, carbon electrode. The current passing at the electrode/electrolyte interface is related to the density of electronic states of the electrode, the concentration of reactant and the rate of electron transfer and the electronic level of the reactant in the solution Here, we study the HET between a conducting polymer electrode and a redox electrolyte, and we found that a new phenomenon is observed. Conducting polymers possess a unique combination of properties compared with most of the inorganic electrodes: acid resistance, the absence of surface-insulating oxide, low temperature and solution processability, a high natural abundance of their elements, molecular porosity. Conducting polymers are in-homogeneous conductors composed of ordered and disordered regions through which electronic transport takes place via percolation paths. We studied the heterogeneous electron transport between the conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) and redox electrolyte ferro/ferricyanide in an aqueous electrolyte. We discovered that the density of percolation paths in the bulk of the material dictates the rate of electron transfer at the electrolyte–polymer electrode interface. This reveals one of the key parameters of designs to achieve efficient electrochemical technologies based on polymer electrodes. We use this finding to optimize the electrical power generated by a thermogalvanic cell (TGC), which is an electrochemical device that converts heat energy into electricity. The power produced by the TGC increased by four orders of magnitude upon changing the morphology and electrical conductivity of the PEDOT electrode. References: Wijeratne K, Vagin M, Brooke R, & Crispin X (2017) Poly(3,4-ethylenedioxythiophene)-tosylate (PEDOT-Tos) electrodes in thermogalvanic J. Mater. Chem. A 5:19619 –19625. Wijeratne K, Ail U, Brooke R, Vagin M, Liu X, Fahlman M, & Crispin X (2018) Bulk electronic transport impacts on electron transfer at conducting polymer electrode-electrolyte interfaces. PNAS, 115:11899 - 11904.

The cathode interface plays a critical role in achieving high-performance fullerene/perovskite planar solar cells. Herein, the simple molecule Isatin and its derivatives are introduced at the back ...

Soft semiconductors are a class of materials that have seen increased interest in terms of both basic research and development of technology, in particular optoelectronic devices. These materials, ...

Radial jet cyclone (RJC) is a new type of dust removal equipment based on the improvement of traditional cyclone which greatly improves the separation efficiency of small size particles and inevitably increases the pressure drop. In order to explore the comprehensive influence of the structure size and process parameters of the radial jet cyclone on its separation efficiency, this paper selected five main influencing factors: blade helix angle, blade length, vortex finder depth, airflow velocity and particle concentration to design a set of orthogonal experiments. Through analysis, the experimental results show that the flow velocity has the greatest influence on the pressure drop, followed by the blade helix angle, and the other three factors have a smaller influence. The insertion depth of the riser has the greatest influence on the separation efficiency. While the smaller the vortex finder depth is, the higher the separation efficiency. The other influencing factors are blade helix angle, airflow velocity, blade length and dust concentration.

We study the filling of single-walled carbon nanotubes (SW- CNTs) with ferrocene molecules. Using e-DIPS SWCNTs with a mean diameter of 1.7nm, we obtain a filling factor as high as 90%. At elevated temperatures in high vacuum the filled SWCNTs are transformed to double-walled carbon nanotubes (DWCNTs). Temperature dependence of inner tube growth is investigated by Raman spectroscopy. The electronic properties of the obtained nanostructures are studied by X-ray photoelectron spectroscopy and near edge X-ray absorption fine structure spectroscopy. It is found that the growth temperature is higher for larger diameter inner tubes. It is demonstrated that ferrocene filling leads to electron doping of SWCNTs.

Cetyltrimethyl ammonium bromide cationic (CTAB) surfactant was used as template for the synthesis of nanoclusters of ZnS composed of nanowires, by hydrothermal method. The structural and morphological studies were performed by using X-ray diffraction (XRD), scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM) techniques. The synthesized ZnS nanoclusters are composed of nanowires and high yield on the substrate was observed. The ZnS nanocrystalline consists of hexagonal phase and polycrystalline in nature. The chemical composition of ZnS nanoclusters composed of nanowires was studied by X-ray photo electron microscopy (XPS). This investigation has shown that the ZnS nanoclusters are composed of Zn and S atoms.

Site selective high resolution photoemission and X-ray absorption have revealed the complex interplay between ferrocene and single-walled carbon nanotubes (SWCNTs) upon filling. The use of ultraclean and metallicity sorted nanotubes as starting material and a subsequent ferrocene filling, yields metallicity sorted hybrids, where the details of the internal charge transfer from Fe to the SWCNTs have been distinctly unravelled. An n-type doping of the SWCNTs has been identified, with the peculiarity that purely metallic tubes are prone up to 30% higher doping than their semiconducting counterparts. Concomitantly, the average Fe valency changes from 2 in ferrocene to 2.3 in the ferrocene/semiconducting SWCNT hybrids and to 2.4 in the ferrocene/metallic SWCNT hybrids. The origin of this extra charge transfer has been revealed to be ionic by resonant photoemission, which excludes a finite hybridization between the ferrocene filler and the SWCNTs. This does not only substantiate that the internal charge transfer determines the resulting electronic transport properties in the filled 1D carbon hybrids, but that the metallic or semiconducting character of the encapsulating tubes is crucial towards tailoring and regulating tunable 1D electronic transport properties in these materials that are highly desirable in nanoelectronics.

Twenty-eight surface sediment samples and one sediment core were analyzed for 21 organochlorine pesticides (OCPs), in order to provide extensive information of distribution, sources, pollution history and ecological risk of these OCP compounds in Daling River area, China. The results showed that hexachlorocyclohexanes (HCHs) and dichlorodiphenyltrichloroethanes (DDTs) were the most frequently detected contaminants in the surface sediment samples with concentrations (in ngg(-1) dry weight (dw)) from 1.1 to 30 and from 2.2 to 45, respectively. Analysis of variance showed significant (P

In this study, Fe3O4 and Co3O4 nanoparticles were prepared by co-precipitation method and sol-gel method respectively. The synthesised nanoparticles were characterised by X-ray diffraction [XRD] an ...

Understanding energy-level alignment and molecular growth characteristics of an organic semiconductor on the graphene surface is crucial for graphene-related device performance. Here we demonstrate that tunable interface properties and molecular orientation can be achieved by modifying graphene films on a SiC substrate with monolayer copper-hexadecafluorophthalocyanine (F16CuPc) molecules. On clean graphene, pentacene molecules form a tilted configuration even at very low coverage (one or two monolayers) rather than flat-lying as on the graphite surface. Pentacene molecules prefer to grow with a (022) plane parallel to the clean graphene surface. With increasing coverage, X-ray adsorption data indicate there is no obvious change of molecular stacking orientation. The corresponding hole injection barrier is about 0.7 eV. On the modified graphene where thin (one or two monolayers) F16CuPc molecules are flat-lying on graphene, an almost perfect up-standing molecular stacking of pentacene film was formed on t...

Organic photovoltaics (OPV) show strong potential for a number of renewable energy applications because of some specifically appealing features (light weight, flexibility, color, …). Over the past decade, the power conversion efficiencies of organic solar cells have strongly risen to values surpassing the 10% threshold, mainly due to strong efforts in chemical engineering of the photoactive components, architectural device optimization and acquisition of fundamental insights in the underlying device physics. As part of the device optimization, the use of conjugated polyelectrolyte (CPE) interfacial layers has been introduced as a popular and powerful way to boost the inherent I-V characteristics. In the presented work, we applied impedance spectroscopy to probe the dielectric permittivity of a series of polythiophene-based CPE interlayer materials as a means to postulate design rules toward novel generation interfacial layers. The presence of ionic pendant groups grants the formation of a capacitive double layer, boosting the charge extraction and device efficiency. A counteracting effect is that the material’s affinity with respect to the underlying photoactive layer diminishes. To enhance the interlayer-photoactive layer compatibility, copolymer structures containing a certain amount of non-ionic side chains are found to be beneficial.

Because solar and wind power produce electricity intermittently, electricity needs to be stored in large batteries composed of materials of high abundancy. X. Crispin and co‐workers demonstrate, in article number 1500305, that paper functionalized with a conducting polymer constitutes a promising electrode for supercapacitors, and potentially batteries. Atomic force microscopy reveals cellulose nanofibers with a conducting polymer coating, as demonstrated in the paper battery of the cover image.

The semiconductor-electrode interface impacts the function and the performance of (opto) electronic devices. For printed organic electronics the electrode surface is not atomically clean leading to weakly interacting interfaces. As a result, solution-processed organic ultrathin films on electrodes typically form islands due to dewetting. It has therefore been utterly difficult to achieve homogenous ultrathin conjugated polymer films. This has made the investigation of the correct energetics of the conjugated polymer-electrode interface impossible. Also, this has hampered the development of devices including ultrathin conjugated polymer layers. Here, LangmuirShafer-manufactured homogenous mono-and multilayers of semiconducting polymers on metal electrodes are reported and the energy level bending using photoelectron spectroscopy is tracked. The amorphous films display an abrupt energy level bending that does not extend beyond the first monolayer. These findings provide new insights of the energetics of the polymer-electrode interface and opens up for new high-performing devices based on ultrathin semiconducting polymers. Funding Agencies|EU project SUNFLOWER of FP7 cooperation programme [287594]; Swedish Research Council [2013-4022]; Goran Gustafsson Foundation for Research in Natural Sciences and Medicine; Swedish Research Council Linnaeus grant LiLi-NFM; Advanced Functional Materials Center at Linkoping University

A novel patterning technique of conductive polymers produced by vapor phase polymerization is demonstrated. The method involves exposing an oxidant film to UV light which changes the local chemical environment of the oxidant and subsequently the polymerization kinetics. This procedure is used to control the conductivity in the conjugated polymer poly(3,4-ethylenedioxythiophene): tosylate by more than six orders of magnitude in addition to producing high-resolution patterns and optical gradients. The mechanism behind the modulation in the polymerization kinetics by UV light irradiation as well as the properties of the resulting polymer are investigated. Funding Agencies|Knut and Alice Wallenberg Foundation [KAW 2011.0050, KAW 2014.0041, KAW 2012.0302]

In this paper, we show that the possibility of using polyethylene glycol (EG) as a hydrogen source and it is used to assist the hydrothermal synthesis of ZnO nanorods (ZNRs). EG doping in ZNRs has been found to significantly improve their optical and chemical sensing characteristics toward glutamate. The EG was found to have no role on the structural properties of the ZNRs. However, the x-ray photoelectron spectroscopy (XPS) suggests that the EG could induce donor impurities effect in ZnO. Photoluminescence (PL) and UV-Vis. spectra demonstrated this doping effect. Mott-Schottky analysis at the ZNRs/electrolyte interface was used to investigate the charge density for the doped ZNRs and showed comparable dependence on the used amount of EG. Moreover, the doped ZNRs were used in potentiometric measurements for glutamate for a range from 10(-6) M to 10(-3) M and the potential response of the sensor electrode was linear with a slope of 91.15 mV/decade. The wide range and high sensitivity of the modified ZNRs based glutamate biosensor is attributed to the doping effect on the ZNRs that is dictated by the EG along with the high surface area-to-volume ratio. The findings in the present study suggest new avenues to control the growth of n-ZnO nanostructures and enhance the performance of their sensing devices. Funding Agencies|University of Kordofan, El-Obeid, Kordofan Sudan [700]

Bones have been shown to exhibit piezoelectric properties, generating electrical potential upon mechanical deformation and responding to electrical stimulation with the generation of mechanical stress. Thus, the effects of electrical stimulation on bone tissue engineering have been extensively studied. However, in bone regeneration applications, only few studies have focused on the use of electroactive 3D biodegradable scaffolds at the interphase with stem cells. Here a method is described to combine the bone regeneration capabilities of 3D-printed macroporous medical grade polycaprolactone (PCL) scaffolds with the electrical and electrochemical capabilities of the conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT). PCL scaffolds have been highly effective in vivo as bone regeneration grafts, and PEDOT is a leading material in the field of organic bioelectronics, due to its stability, conformability, and biocompatibility. A protocol is reported for scaffolds functionalization with PEDOT, using vapor-phase polymerization, resulting in a conformal conducting layer. Scaffolds' porosity and mechanical stability, important for in vivo bone regeneration applications, are retained. Human fetal mesenchymal stem cells proliferation is assessed on the functionalized scaffolds, showing the cytocompatibility of the polymeric coating. Altogether, these results show the feasibility of the proposed approach to obtain electroactive scaffolds for electrical stimulation of stem cells for regenerative medicine. Funding agencies: Knut and Alice Wallenberg Foundation [KAW 2012.0302]; Nanyang Technological University

The color of polymer solar cells using an opaque electrode is given by the refl ected light, which depends on the composition and thickness of each layer of the device. Metal-oxide-based optical spacers are intensively studied in polymer solar cells aiming to optimize the light absorption. However, the low conductivity of materials such as ZnO and TiO 2 limits the thickness of such optical spacers to tenths of nanometers. A novel synthesis route of cluster-free Al-doped ZnO (AZO) nanocrystals (NCs) is presented for solution processing of highly conductive layers without the need of temperature annealing, including thick optical spacers on top of polymer blends. The processing of 80 nm thick optical spacers based on AZO nanocrystal solutions on top of 200 nm thick polymer blend layer is demonstrated leading to improved photocurrent density of 17% compared to solar cells using standard active layers of 90 nm in com-bination with thin ZnO-based optical spacers. These AZO NCs also open new opportunities for the processing of high-effi ciency color tuned solar cells. For the fi rst time, it is shown that applying solution-processed thick optical spacer with polymer blends of different thicknesses can process solar cells of similar effi ciency over 7% but of different colors. EU FP7-ICT-2011-7 287594 SFUMATO-FUI Project AAP12 Generalitat Valenciana (Project Institute of Nanotechnologies for Clean Energies) ISIC/2012/008

In electronics, the fi eld-effect transistor (FET) is a crucial cornerstone and successful integration of this semiconductor device into circuit applications requires stable and ideal electrical characteristics over a wide range of temperatures and environments. Solution processing, using printing or coating techniques, has been explored to manufacture organic fi eld-effect transistors (OFET) on fl exible carriers, enabling radically novel electronics applications. Ideal electrical characteristics, in organic materials, are typically only found in single crystals. Tiresome growth and manipulation of these hamper practical production of fl exible OFETs circuits. To date, neither devices nor any circuits, based on solution-processed OFETs, has exhibited an ideal set of characteristics similar or better than today’s FET technology based on amorphous silicon. Here, bar-assisted meniscus shearing of dibenzo-tetrathiafulvalene to coat-process self-organized crystalline organic semiconducting domains with high reproducibility is reported. Including these coatings as the channel in OFETs, electric fi eld and temperature-independent charge carrier mobility and no bias stress effects are observed. Furthermore, record-high gain in OFET inverters and exceptional operational stability in both air and water are measured., The authors thank the ERC StG 2012-306826 e-GAMES project, the Networking Research Center on Bioengineering, Biomaterials, and Nanomedicine (CIBER-BBN), the DGI (Spain) project BE-WELL CTQ2013-40480-R, and the Generalitat de Catalunya (2014-SGR- 17). Research in Sweden was fi nancially supported by the Advanced Functional Materials Center at Linköping University, the Önnesjö Foundation, the Knut and Alice Wallenberg Foundation (Power Paper project, scholars), the Swedish Foundation for Strategic Research (SSF, Synergi project). F.G.D.P. thanks Universidad Técnica de Ambato and Secretaría de Educación Superior, Ciencia, Tecnología e Innovación for funding through a doctoral scholarship “Convocatoria abierta 2010.” The authors also thank Witold Tatkiewicz for his help with the ImageJ software.

The nature of the electronic and local magnetic properties of ferrocene (FeCp2) filled single-walled carbon nanotubes (SWCNT) has been investigated by X-ray absorption spectroscopy (XAS) and magnetic circular dichroism (XMCD). Metallic, semiconducting, and unsorted ferrocene-filled tubes have been studied in different conditions of temperature and magnetic field. XMCD signal becomes evident with the application of a magnetic field at low temperature. We find that the molecular states of ferrocene interact with SWCNT of different metallicities. A paramagnetic behavior of encapsulated ferrocene is observed from the magnetic field dependent XMCD measurements which is consistent with theoretical predictions.

Significant influence on the thermal stability of polyaniline (PANI) in the presence of multi-walled carbon nanotubes (MWCNTs) is reported. By means of in-situ rapid mixing approach, water-dispersible nanofibrillar PANI and composites, consisting of MWCNTs uniformly coated with PANI in the state of emeraldine salt, with a well-defined core-shell heterogeneous structure, were prepared. The de-protonation process in PANI occurs at a lower temperature under the presence of MWCNTs on the polyaniline composite upon thermal treatment. However, it is found that the presence of MWCNTs significantly enhances the thermal stability of PANIs backbone upon exposure to laser irradiation, which can be ascribed to the core-shell heterogeneous structure of the composite of MWCNTs and PANI, and the high thermal conductivity of MWCNTs. Funding Agencies|Swedish Governmental Agency for Innovation Systems (VINNOVA) through VINN Excellence iPack Center||Swedish Research Council (VR)|2009-8068

D. Haberer*,1, L. Petaccia2, Y. Wang3, H. Quian3, M. Farjam4, S. A. Jafari4,5, H. Sachdev6,7, A. V. Federov8, D. Usachov8, D. V. Vyalikh8,9, X. Liu10, O. Vilkov8,9, V. K. Adamchuk8, S. Irle3, M. Knupfer1, B. Buchner1, and A. Gruneis1,10 1 IFW Dresden, P.O. Box 270116, 01171 Dresden, Germany 2 Elettra Synchrotron Light Laboratory, Sincrotrone Trieste SCpA, S.S. 14 Km 163.5, 34149 Trieste, Italy 3 Department of Chemistry, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan 4 Institute for Research in Fundamental Sciences (IPM), P.O. Box 19395-5531, Tehran, Iran 5 Department of Physics, Sharif University of Technology, Tehran 11155-9161, Iran 6 Anorganische Chemie 8.11, Universitat des Saarlandes, 66041 Saarbrucken, Germany 7 Max-Planck-Institut fur Polymerforschung, Ackermannweg 10, 55128 Mainz, Germany 8 St. Petersburg State University, St. Petersburg 198504, Russia 9 Institut fur Festkorperphysik, TU Dresden, Mommsenstrasse 13, 01069 Dresden, Germany 10 Faculty of Physics, University of Vienna, Strudlhofgasse 4, 1090 Wien, Austria

We have investigated the C1s core level X-ray absorption of bulk samples of C60-peapods and double wall carbon nanotubes (DWNTs) derived from either metallic or semiconducting single-walled carbon nanotubes (SWNTs). The clear cut separation of the different species unveils their distinct electronic van Hove singularities (VHS). The core level spectra of peapods are a quantitative superpositon of the conduction band of nanotubes and unoccupied molecular orbitals of C60. The outer shell metallicity selected DWNTs reveal changes in the π* resonance due to the inner shell VHS.

The growth of inner tubes from ferrocene-filled single-walled carbon nanotubes was studied with Raman spectroscopy. Special attention was paid to inner tubes formation based on the annealing temperature and the outer tube diameter. Besides the presence of inner tubes radial breathing mode, a new Raman feature appears around 1250 cm−1, which is always related to the appearance of the inner tube. The thermal stability of the inner tube strongly depends on the outer tube diameter. The inner tube formed inside outer tube with 1 nm diameter is destructed at 1000 °C, but it can survive more than 1300 °C with outer tube diameter of about 1.6 nm. Furthermore, the splitting of G line and the shift of 2D line were discussed regarding to the appearance of inner tubes.

We present the surface electronic and magnetic properties of half-metal La0.6Sr0.4MnO3 (LSMO) thin film modified by a simple cleaning procedure, the so-called SC1 (5 H2O, 1 NH4OH, 1 H2O2), at 85 °C...

Dechloranes, including Dechlorane Plus (DP), Mirex (Dechlorane), Dechlorane 602 (Dec 602), Dechlorane 603 (Dec 603), and Dechlorane 604 (Dec 604), were determined using GC-MSD for water, sediment and oyster samples collected at 15 sampling sites near the Bohai and Huanghai Sea shore area of northern China in 2008. DP and Mirex were detected in most water, sediment, and oyster samples, which indicated widespread distribution of these two compounds. The mean concentrations in water, sediment and oyster samples, respectively, were 1.8 ng/L, 2.9 ng/g dry weight (dw) and 4.1 ng/g wet weight (ww) for total DP, and 0.29 ng/L, 0.90 ng/g dw, and 2.0 ng/g ww for Mirex. Dec 602 and Dec 603 were not detected in water but in small portions of the sediment and oyster samples, showing a low level of contamination by these two chemicals in the region. Strong and significant correlations were found between total DP and Mirex concentrations in water, sediment and oyster samples, probably suggesting similar local sources of these two chemicals. Dec 604 was not found in any samples. The biota-sediment accumulation factor (BSAF) of DP, Mirex, and Dec 602 declined along with the increase of their logarithm of octanol-water partition coefficients (log Kow), possibly indicating that compounds with lower log Kow (like Mirex and Dec 602) accumulated more readily in biota. The mean fractional abundance of syn-DP (fsyn) was 0.34 in water samples, a value lower than that in Chinese commercial mixture (0.41), while the mean fsyn for surface sediment (0.44) and oyster (0.45) samples were higher than technical values. Enrichment of syn-DP in oyster was in agreement with previously reported findings in Great Lakes fish. Enrichment of syn-DP in marine surface sediments, however, is contrary to data reported for fresh water sediments. To our knowledge this is the first report of Dec 602, Dec 603, and Dec 604 in a marine environment and also the first report of Dechloranes in marine biota.

Organometal halide perovskites exhibit a bright future for applications in solar cells, as efficiency has achieved over 22%. The long-term stability remains a major obstacle for commercialization. ...

Spinterface engineering has shown quite important roles in organic spintronics as it can improve spin injection or extraction. In this study, 11,11,12,12‐tetracyanonaptho‐2,6‐quinodimethane (TNAP) is introduced as an interfacial layer for a prototype interface of Fe/TNAP. An element‐specific investigation of the electronic and magnetic structures of Fe/TNAP system by use of near edge X‐Ray absorption fine structure (NEXAFS) and X‐ray magnetic circular dichroism (XMCD) is reported. Strong hybridization between TNAP and Fe and induced magnetization of N atoms in TNAP molecule are observed. XMCD sum rule analysis demonstrates that the adsorption of TNAP reduces the spin moment of Fe by 12%. In addition, induced magnetization in N K‐edge of TNAP is also found with other commonly used ferromagnets in organic spintronics, such as La0.7Sr0.3MnO3 and permalloy, which makes TNAP a very promising molecule for spinterface engineering in organic spintronics.

A free-standing high-output power density polymeric thermoelectric (TE) device is realized based on a highly conductive (approximate to 2500 S cm(-1)) structure-ordered poly(3,4-ethylenedioxythiophene):polystyrene sulfonate film (denoted as FS-PEDOT:PSS) with a Seebeck coefficient of 20.6 mu V K-1, an in-plane thermal conductivity of 0.64 W m(-1) K-1, and a peak power factor of 107 mu W K-2 m(-1) at room temperature. Under a small temperature gradient of 29 K, the TE device demonstrates a maximum output power density of 99 +/- 18.7 mu W cm(-2), which is the highest value achieved in pristine PEDOT:PSS based TE devices. In addition, a fivefold output power is demonstrated by series connecting five devices into a flexible thermoelectric module. The simplicity of assembling the films into flexible thermoelectric modules, the low out-of-plane thermal conductivity of 0.27 W m(-1) K-1, and free-standing feature indicates the potential to integrate the FS-PEDOT:PSS TE modules with textiles to power wearable electronics by harvesting human bodys heat. In addition to the high power factor, the high thermal stability of the FS-PEDOT:PSS films up to 250 degrees C is confirmed by in situ temperature-dependent X-ray diffraction and grazing incident wide angle X-ray scattering, which makes the FS-PEDOT:PSS films promising candidates for thermoelectric applications. Funding Agencies|Vinnova Marie Curie incoming project [2016-04112]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [200900971]; Recruitment Program of Global Youth Experts; National Natural Science Foundation of China [21474035]; United States National Science Foundation [DMR-1262261]; Open Fund of the State Key Laboratory of Luminescent Materials and Devices [2016-skllmd-03]; European Research Council [ERC 307596]

Levels of organochlorine pesticides (OCPs) were analyzed in mollusk samples collected from markets in Dalian, China. Among 14 OCPs screened, chlordane (Chls), dichlorodiphenyltrichloroethane (DDT) and 1,2,3,4,5,6-hexachlorocyclohexane (HCH) were dominant compounds with the medians of 30.2, 5.31 and 2.03 ng/g wet weight (ww), respectively. Source analysis showed that, much higher concentrations of Chls in mollusk samples were the result of usage of the chemical in the city, HCH in samples were mainly due to historical technical HCH usage, and a small amount of fresh use of DDT might exist, causing high portion of p,p'-DDT in samples. Cumulative distribution functions for the concentrations of the selected OCPs were compared to several threshold criteria, indicating that concentrations in most mollusk samples were lower than the safe lines. The concentration data of selected OCPs were used for risk assessment, and human exposure levels were compared to noncancer and cancer benchmarks.

The schematic visualization of the Alq(3) molecule on the Fe substrate with the optimized geometry at lowest total energy. When the Alq(3) molecule is relaxed on the surface, only two of the wings are lying down on the Fe surface, and the third wing remains perpendicular to the surface, showing a strong hybridization occurance.

The structure and morphology of mixed GaOx/WOx thin film systems prepared by either sequential or simultaneous oxide deposition has been studied by Analytical (High-Resolution) Transmission Electron Microscopy (TEM), Selected Area Electron Diffraction (SAED), X-ray Photoelectron Spectroscopy (XPS) and Atomic Force Microscopy (AFM). GaOx and WOx were prepared by thermal evaporation of the corresponding oxides (β-Ga2O3 and WO3, respectively) in 10−2 Pa oxygen onto a NaCl substrate, which was held at temperatures between 298 and 580 K. The film morphology of differently prepared mixed GaOx/WOx films not only differs significantly from those of the pure oxides, but also strongly depends on the preparation conditions and the order of deposition. Upon co-deposition of GaOx/WOx films onto NaCl(0 0 1) at temperatures above 580 K a gallia morphology was observed, which is strikingly different from hitherto reported pure GaOx films, i.e., growth of small-diameter (20–25 nm) sub-stoichiometric gallia dendrites. The dendritic growth is apparently mediated by the GaOx/NaCl(0 0 1) contact area rather than being an intrinsic feature of the three-dimensional mixed-oxide bulk. In particular, neither sequentially deposited GaOx/WOx films nor co-deposited films on top of a pre-deposited WOx interlayer exhibited this peculiar morphology.

Work function (WF) modification of metal electrodes by adsorbing electron-rich or electron-deficient molecules oil metal surfaces has become a field of significant interest. The barrier for charge carrier injection in organic semiconductor devices can be reduced by molecular adsorption, leading to all interfacial dipole. Here, we demonstrate that the WF of noble metals such as ALL call be decreased significantly by adsorbing air stable n-type dopant acridine orange base (AOB) thin film. When a (sub)monolayer AOB is deposited on sputter-cleaned Au, the WF of the substrate changes from 5.2 to 3.5 eV. At complete coverage of the Au Surface, the WF is further reduced to 3.3 eV. When a (sub) monolayer of AOB is inserted between Au and C-60 thin film, the barrier of electron injection is decreased by 0.4 +/- 0.1 eV as compared to an Au-C-60 interface without AOB. Polymer solar cells with AOB/Au as a cathode have a similar open circuit voltage and comparable power conversion efficiency with devices using LiF/Al as a cathode, demonstrating that the AOB-modified gold electrode is an efficient low-work-function contact. Given the low positive pinning energy of 3.3 eV for AOB, we expect that other conventional high-work-function materials (Ag, ITO. La0.7Sr0.3MnO3 and even PEDOT:PSS) can be modified by AOB as effectively as Au.

Chemical polymerization of a 3,4-ethylenedioxythiophene derivative bearing a sulfonate group (EDOT-S) is reported. The polymer, PEDOT-S, is fully water-soluble and has been produced by polymerizing EDOT-S in water, using Na2S2O8 and a catalytic amount of FeCl3. Elemental analysis and XPS measurements indicate that PEDOT-S is a material with a substantial degree of self-doping, but also contains free sulfate ions as charge-balancing counterions of the oxidized polymer. Apart from self-doping PEDOT-S, the side chains enable full water solubility of the material; DLS studies show an average cluster size of only 2 nm. Importantly, the solvation properties of the PEDOT-S are reflected in spin-coated films, which show a surface roughness of 1.2 nm and good conductivity (12 S/cm) in ambient conditions. The electro-optical properties of this material are shown with cyclic voltammetry and spectroelectrochemical experiment reveals an electrochromic contrast (∼48% at λmax = 606 nm).

The present work aimed at developing in silico models allowing for a reliable prediction of bioaccumulative compounds and non-bioaccumulative compounds based on the definition of Bioconcentration Factor (BCF) using a diverse data set of 238 organic molecules. The partial least squares analysis (PLS), C4.5, support vector machine (SVM), and random forest (RF) algorithms were applied, and their performance classifying these compounds in terms of their quantitative structure-activity relationships (QSAR) was evaluated and verified with 5-fold cross-validation and an independent evaluation data set. The obtained results show that the overall prediction accuracies (Q) of the optimal PLS, C4.5, SVM and RF models are 84.5-87.7% for the internal cross-validation, with prediction accuracy (CO) of 86.3-91.1% in the external test sets, and C4.5 is slightly better than the three other methods which presents a Q of 87.7%, and a CO of 91.1% for the test sets. All these results prove the reliabilities of the in silico models, which should be valuable for the environmental risk assessment of the substances.

Gallium oxide thin films were prepared by thermal evaporation and deposition of Ga 2 O 3 on NaCl(001) cleavage planes at varying substrate temperatures, oxygen pressures and deposition rates. The structure of the so-prepared thin films was checked by Transmission Electron Microscopy and Selected Area Diffraction and also characterized by X-ray Photoelectron Spectroscopy and Atomic Force Microscopy, both in the as-deposited state and after different oxidative and reductive treatments. The substrate temperature proved to be most crucial for the structure of the gallium oxide films, ranging from low-contrast amorphous structures at low substrate temperatures (298 K) to nanosphere structures at higher temperatures (580 K). The stability of the films was found to be mainly determined by the interaction of substrate temperature and deposition rate. Crystalline β-Ga 2 O 3 structures were obtained after oxidative, reductive and annealing treatments at and beyond 773 K suggesting that the crystallization is mainly a thermal annealing effect.

The structure, morphology and composition of pure WO3 thin films deposited onto vacuum-cleaved NaCl(001) single crystals have been studied at different substrate temperatures up to 580 K and under different oxidative and reductive treatments in the temperature range 373–873 K by Transmission Electron Microscopy, Selected-Area Electron Diffraction and X-ray Photoelectron Spectroscopy (XPS). A transition from an amorphous structure obtained after deposition at 298 K to a more porous structure with small crystallites at the highest substrate temperatures has been observed. XPS spectra reveal the presence of W6+ irrespective of the preparation procedure. Significant changes in the film structure were only observed after an oxidative treatment in 1 bar O2 at 673 K, which induces crystallization of a monoclinic WO3 structure. After raising the oxidation temperature to 773 K, the film shows additional reconstruction and a hexagonal WO3 structure becomes predominant. This hexagonal structure persists at least up to 873 K oxidation temperature. However, these structural transformations observed upon oxidation were almost completely suppressed by mixing the WO3 thin film with a second oxide, e.g. Ga2O3. Reduction of the WO3 films in 1 bar H2 at 723–773 K eventually induced the formation of the β-W metal structure, as evidenced by electron diffraction and XPS.

Nanocrystalline diamond (NCD) has recently been successfully utilized in a variety of life science applications. NCD films are favorable and salubrious substrates for cells during cultivation. Therefore NCD has also been employed in tissue engineering strategies. NCD as reported in this contribution was grown by means of a modified hot-filament chemical vapor deposition technique, which results in less than 3% sp2-hybridization and yields grain sizes of 5–20 nm. After production the NCD surface was rather hydrophobic, however it could be efficiently refined to exhibit more hydrophilic properties. Changing of the surface structure was found to be an efficient means to influence growth and differentiation capacity of a variety of cells. The particular needs for any given cell type has to be proven empirically. Yet flexible features of NCD appear to be superior to plastic surfaces which can be hardly changed in quality. Besides its molecular properties, crystal structural peculiarities of NCD appear to influence cell growth as well. In our attempt to facilitate, highly specialized applications in biomedicine, we recently discovered that growth factors can be tightly bound to NCD by mere physisorption. Hence, combination of surface functionalization together with further options to coat NCD with any kind of three-dimensional structure opens up new avenues for many more applications. In fact, high through-put protein profiling of early disease stages may become possible from serum samples, because proteins bound to NCD can now be efficiently analyzed by MALDI/TOF-MS. Given these results, it is to be presumed that the physical properties and effective electrochemical characteristics of NCD will allow tailoring devices suitable for many more diagnostic as well as therapeutic applications.

High anisotropy L1(0) ordered FePt thin films are considered to have high potential for use as high areal density recording media, beyond 1 Tera bit/in2. In this paper, we review recent results on the synthesis and magnetic properties of L1(0) FePt nanocomposite films. Several fabrication methods have been developed to produce high-anisotropy FePt films: epitaxial and non-epitaxial growth of (001)-oriented FePt:X (X = Au, Ag, Cu, C, etc.) composite films that might be used for perpendicular media; monodispersed FePt nanocluster-assembled films grown with a gas-aggregation technique and having uniform cluster size and narrow size distribution; self-assembled FePt particles prepared with chemical synthesis by reduction/decomposition techniques, etc. The magnetic properties are controllable through variations in the nanocluster properties and nanostructure. FePt and related films show promise for development as heat-assisted magnetic recording media at extremely high areal densities. The self-assembled FePt arrays show potential for approaching the ultimate goal of single-grain-per-bit patterned media.

The structural and electronic properties of nanocrystalline diamond films synthesized by a modified hot-filament chemical vapour deposition process were investigated by both bulk- and surface-sensitive techniques. Diffraction and microscopy data show the films to consist of diamond grains with an average crystallite size of about 10–15 nm and a root-mean-square roughness of similar size. Carbon core-level excitations in transmission electron energy-loss spectroscopy reveal an sp 2 content below 5%. The low energy loss spectra are quite similar to that of diamond crystal. The high sp 3 content in the films was also confirmed by C 1 s photoelectron plasmon energy loss features in X-ray photoemission experiments and by X-ray excited Auger-electron spectroscopy. We find that the hydrogen covered diamond surface gets contaminated after storage for several months under ambient conditions. Heating up to 500 °C in vacuo is required to desorb the adsorbate layer.