ABSTRACT We present a study on the formation mechanism of copper zinc tin sulphide (CZTS) nanopar... more ABSTRACT We present a study on the formation mechanism of copper zinc tin sulphide (CZTS) nanoparticles prepared from metal salts and 1-dodecanethiol in oleylamine. The nanoparticle sample exhibits two kinds of crystals, large ones with a size of about 70 nm and smaller ones with a diameter of about 25 nm. Analysis of the chemical composition of single nanoparticles revealed that the small nanoparticles consist of copper sulphide, while the larger ones are CZTS nanoparticles. A thorough investigation of the formation process of the nanoparticles revealed that the presence of the copper sulphide nanoparticles originates from the formation of copper sulphide nanopartides in the initial nucleation step. These initial copper sulphide nanoparticles are converted to copper tin sulphide before the final CZTS nanoparticles are obtained.
ABSTRACT Solution processable small molecules are an alternative to conjugated polymers in organi... more ABSTRACT Solution processable small molecules are an alternative to conjugated polymers in organic photovoltaics and have recently been in the focus of intense research. In this work, organic–inorganic hybrid solar cells with active layers consisting of the solution-processable small-molecule p-DTS(FBTTh2)2 and copper indium sulfide nanoparticles are presented. The copper indium sulfide nanoparticles are formed in situ directly in the small molecule matrix from metal xanthate precursors. The prepared nanocomposite small molecule/copper indium sulfide films are very smooth, highlighting the good compatibility of p-DTS(FBTTh2)2 with the in situ preparation of metal sulfide nanoparticles. The formed nanoparticles have diameters of about 3 nm. Hybrid solar cells, exhibiting power conversion efficiencies of 1.3%, are characterized by IV curves, EQE spectra and electron microscopy.
ABSTRACT Besides active materials the choice of suitable cathodes is crucial for a good overall p... more ABSTRACT Besides active materials the choice of suitable cathodes is crucial for a good overall performance in solar cells. A cathode modification utilizing a thin silver interlayer followed by an aluminum layer can largely enhance the fill factor of polymer: CIS (copper indium sulfide) solar cells in comparison to pure Al or Ag cathodes. In this work, we investigate if this concept can also be applied to polymer: fullerene solar cells to enhance their overall power conversion efficiency. The organic solar cells examined consisted of blends of low band-gap donor polymers (PCDTBT and PSiF-DBT) as well as PCBM as acceptor.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was e... more ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ABSTRACT We report on the formation of one-dimensional Au/Ag core-shell nanostructures in superfl... more ABSTRACT We report on the formation of one-dimensional Au/Ag core-shell nanostructures in superfluid helium nanodroplets (He-N) and their subsequent surface deposition under soft landing conditions. In vortex charged He-N, dopant atoms and clusters prefer to agglomerate along vortex cores, which serve as personal cryo-templates for each nanowire. A sequential pickup scheme enables the fabrication of Au/Ag structures with either Au as core and Ag as shell or vice versa. The core-shell structure is in both cases shown by energy-dispersive x-ray spectroscopy (EDX) in a scanning transmission electron microscope (STEM). The inherent spatial resolution and element sensitivity of this method allows a direct observation of the two different phases. High resolution STEM studies elucidate morphological details of the Au/Ag nanostructures and, together with the EDX analysis, indicate that the nanowires are formed in a multicenter aggregation process.
... caused by chromatic aberrations of the post specimen lenses as pointed out by Egerton (1984) ... more ... caused by chromatic aberrations of the post specimen lenses as pointed out by Egerton (1984) and by Malis et a!. Ferdinand Hofer and ... Unless allowance for the chromatic aberration effects of the post specimen lenses is made (Craven et a!., 1981), the implication appears to be ...
... In this Chapter, we will focus on fixed beam EFTEM and its specific use in addressing questio... more ... In this Chapter, we will focus on fixed beam EFTEM and its specific use in addressing questions regarding the micro-and nanochemistry of various ... Additionally, we intend for this chapter to provide a literature survey including most materials science applications of EFTEM. ...
Quantitative microanalysis by electron energy-loss spectrometry requires knowledge of partial inn... more Quantitative microanalysis by electron energy-loss spectrometry requires knowledge of partial inner-shell ionization cross-sections. Data for the L23-edges of the elements strontium to molybdenum are not well known. We have therefore measured cross-section ratios (k-factors) for the L23-edges of the elements Sr to Mo using thin film oxide-standards. The experimental values are compared with calculations derived from a modified hydrogenic and
Summary. Thin-film electrodes allow the manufacturing of flat batteries of variable design. The... more Summary. Thin-film electrodes allow the manufacturing of flat batteries of variable design. Their electric performance is better than that of customary cells because of a larger contact area between anode and cathode and better utilization of the electrochemically active materials. Bipolar thin-film electrodes for the rechargeable alkaline zinc/manganese dioxide system were assembled using graphite-filled plastics (high-density polyethylene and polyisobutylene). In a
Summary. Energy-filtering transmission electron microscopy (EFTEM) and electron energy-loss spe... more Summary. Energy-filtering transmission electron microscopy (EFTEM) and electron energy-loss spectrometry (EELS) have been used to measure the distribution of titanium in titanium-doped electrolytic manganese dioxide, which consists of large particle agglomerates of some micrometer diameter. In contrast to previous investigations, where the distribution of the doping elements can only be investigated at the thinnest regions of the agglomerates, we describe an
Energy-filtering transmission electron microscopy (EFTEM) has been used for imaging of secondary ... more Energy-filtering transmission electron microscopy (EFTEM) has been used for imaging of secondary phases in materials, e.g. precipitates and grain boundary phases. The investigations have been performed with a Philips CM20 equipped with a Gatan imaging filter at 200 kV acceleration voltage. In order to visualize the secondary phases in a steel sample we have recorded jump ratio images using the
ABSTRACT We present a study on the formation mechanism of copper zinc tin sulphide (CZTS) nanopar... more ABSTRACT We present a study on the formation mechanism of copper zinc tin sulphide (CZTS) nanoparticles prepared from metal salts and 1-dodecanethiol in oleylamine. The nanoparticle sample exhibits two kinds of crystals, large ones with a size of about 70 nm and smaller ones with a diameter of about 25 nm. Analysis of the chemical composition of single nanoparticles revealed that the small nanoparticles consist of copper sulphide, while the larger ones are CZTS nanoparticles. A thorough investigation of the formation process of the nanoparticles revealed that the presence of the copper sulphide nanoparticles originates from the formation of copper sulphide nanopartides in the initial nucleation step. These initial copper sulphide nanoparticles are converted to copper tin sulphide before the final CZTS nanoparticles are obtained.
ABSTRACT Solution processable small molecules are an alternative to conjugated polymers in organi... more ABSTRACT Solution processable small molecules are an alternative to conjugated polymers in organic photovoltaics and have recently been in the focus of intense research. In this work, organic–inorganic hybrid solar cells with active layers consisting of the solution-processable small-molecule p-DTS(FBTTh2)2 and copper indium sulfide nanoparticles are presented. The copper indium sulfide nanoparticles are formed in situ directly in the small molecule matrix from metal xanthate precursors. The prepared nanocomposite small molecule/copper indium sulfide films are very smooth, highlighting the good compatibility of p-DTS(FBTTh2)2 with the in situ preparation of metal sulfide nanoparticles. The formed nanoparticles have diameters of about 3 nm. Hybrid solar cells, exhibiting power conversion efficiencies of 1.3%, are characterized by IV curves, EQE spectra and electron microscopy.
ABSTRACT Besides active materials the choice of suitable cathodes is crucial for a good overall p... more ABSTRACT Besides active materials the choice of suitable cathodes is crucial for a good overall performance in solar cells. A cathode modification utilizing a thin silver interlayer followed by an aluminum layer can largely enhance the fill factor of polymer: CIS (copper indium sulfide) solar cells in comparison to pure Al or Ag cathodes. In this work, we investigate if this concept can also be applied to polymer: fullerene solar cells to enhance their overall power conversion efficiency. The organic solar cells examined consisted of blends of low band-gap donor polymers (PCDTBT and PSiF-DBT) as well as PCBM as acceptor.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was e... more ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ABSTRACT We report on the formation of one-dimensional Au/Ag core-shell nanostructures in superfl... more ABSTRACT We report on the formation of one-dimensional Au/Ag core-shell nanostructures in superfluid helium nanodroplets (He-N) and their subsequent surface deposition under soft landing conditions. In vortex charged He-N, dopant atoms and clusters prefer to agglomerate along vortex cores, which serve as personal cryo-templates for each nanowire. A sequential pickup scheme enables the fabrication of Au/Ag structures with either Au as core and Ag as shell or vice versa. The core-shell structure is in both cases shown by energy-dispersive x-ray spectroscopy (EDX) in a scanning transmission electron microscope (STEM). The inherent spatial resolution and element sensitivity of this method allows a direct observation of the two different phases. High resolution STEM studies elucidate morphological details of the Au/Ag nanostructures and, together with the EDX analysis, indicate that the nanowires are formed in a multicenter aggregation process.
... caused by chromatic aberrations of the post specimen lenses as pointed out by Egerton (1984) ... more ... caused by chromatic aberrations of the post specimen lenses as pointed out by Egerton (1984) and by Malis et a!. Ferdinand Hofer and ... Unless allowance for the chromatic aberration effects of the post specimen lenses is made (Craven et a!., 1981), the implication appears to be ...
... In this Chapter, we will focus on fixed beam EFTEM and its specific use in addressing questio... more ... In this Chapter, we will focus on fixed beam EFTEM and its specific use in addressing questions regarding the micro-and nanochemistry of various ... Additionally, we intend for this chapter to provide a literature survey including most materials science applications of EFTEM. ...
Quantitative microanalysis by electron energy-loss spectrometry requires knowledge of partial inn... more Quantitative microanalysis by electron energy-loss spectrometry requires knowledge of partial inner-shell ionization cross-sections. Data for the L23-edges of the elements strontium to molybdenum are not well known. We have therefore measured cross-section ratios (k-factors) for the L23-edges of the elements Sr to Mo using thin film oxide-standards. The experimental values are compared with calculations derived from a modified hydrogenic and
Summary. Thin-film electrodes allow the manufacturing of flat batteries of variable design. The... more Summary. Thin-film electrodes allow the manufacturing of flat batteries of variable design. Their electric performance is better than that of customary cells because of a larger contact area between anode and cathode and better utilization of the electrochemically active materials. Bipolar thin-film electrodes for the rechargeable alkaline zinc/manganese dioxide system were assembled using graphite-filled plastics (high-density polyethylene and polyisobutylene). In a
Summary. Energy-filtering transmission electron microscopy (EFTEM) and electron energy-loss spe... more Summary. Energy-filtering transmission electron microscopy (EFTEM) and electron energy-loss spectrometry (EELS) have been used to measure the distribution of titanium in titanium-doped electrolytic manganese dioxide, which consists of large particle agglomerates of some micrometer diameter. In contrast to previous investigations, where the distribution of the doping elements can only be investigated at the thinnest regions of the agglomerates, we describe an
Energy-filtering transmission electron microscopy (EFTEM) has been used for imaging of secondary ... more Energy-filtering transmission electron microscopy (EFTEM) has been used for imaging of secondary phases in materials, e.g. precipitates and grain boundary phases. The investigations have been performed with a Philips CM20 equipped with a Gatan imaging filter at 200 kV acceleration voltage. In order to visualize the secondary phases in a steel sample we have recorded jump ratio images using the
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