7 research outputs found
fully solution processed conductive films based on colloidal copper selenide nanosheets for flexible electronics
A novel colloidal synthesis of copper selenide nanosheets (NSs) with lateral dimensions of up to 3 μm is developed. This material is used for the fabrication of flexible conductive films prepared via simple drop-casting of the NS dispersions without any additional treatment. The electrical performance of these coatings is benchmarked against copper selenide spherical nanocrystals (SNCs) in order to demonstrate the advantage of 2D morphology of the NSs for flexible electronics. In this contest, Cu2−xSe SNC films exhibit higher conductivity but lower reproducibility due to the formation of cracks leading to discontinuous films. Furthermore, the electrical properties of the films deposited on different flexible substrates following their bending, stretching and folding are studied. A comparison of Cu2−xSe SNC and CuSe NS films reveals an increased stability of the CuSe NS films under mechanical stress applied to the samples and their improved long-term stability in air
Mapping the Hsp90 Genetic Interaction Network in Candida albicans Reveals Environmental Contingency and Rewired Circuitry
The molecular chaperone Hsp90 regulates the folding of diverse signal transducers in all eukaryotes, profoundly affecting cellular circuitry. In fungi, Hsp90 influences development, drug resistance, and evolution. Hsp90 interacts with ∼10% of the proteome in the model yeast Saccharomyces cerevisiae, while only two interactions have been identified in Candida albicans, the leading fungal pathogen of humans. Utilizing a chemical genomic approach, we mapped the C. albicans Hsp90 interaction network under diverse stress conditions. The chaperone network is environmentally contingent, and most of the 226 genetic interactors are important for growth only under specific conditions, suggesting that they operate downstream of Hsp90, as with the MAPK Hog1. Few interactors are important for growth in many environments, and these are poised to operate upstream of Hsp90, as with the protein kinase CK2 and the transcription factor Ahr1. We establish environmental contingency in the first chaperone network of a fungal pathogen, novel effectors upstream and downstream of Hsp90, and network rewiring over evolutionary time
Fully Solution‐Processed Conductive Films Based on Colloidal Copper Selenide Nanosheets for Flexible Electronics
A novel colloidal synthesis of copper selenide nanosheets (NSs) with lateral dimensions of up to 3 μm is developed. This material is used for the fabrication of flexible conductive films prepared via simple drop-casting of the NS dispersions without any additional treatment. The electrical performance of these coatings is benchmarked against copper selenide spherical nanocrystals (SNCs) in order to demonstrate the advantage of 2D morphology of the NSs for flexible electronics. In this contest, Cu2−xSe SNC films exhibit higher conductivity but lower reproducibility due to the formation of cracks leading to discontinuous films. Furthermore, the electrical properties of the films deposited on different flexible substrates following their bending, stretching and folding are studied. A comparison of Cu2−xSe SNC and CuSe NS films reveals an increased stability of the CuSe NS films under mechanical stress applied to the samples and their improved long-term stability in air
Generalized One-Pot Synthesis of Copper Sulfide, Selenide-Sulfide, and Telluride-Sulfide Nanoparticles
Here we report a facile approach
to synthesize copper chalcogenide
(Cu<sub>2–<i>x</i></sub>S, Cu<sub>2–<i>x</i></sub>Se<sub><i>y</i></sub>S<sub>1–<i>y</i></sub> and Cu<sub>2–<i>x</i></sub>Te<sub><i>y</i></sub>S<sub>1–<i>y</i></sub>)
nanocrystals without employing hot-injection, at moderate reaction
temperatures (200–220 °C) and free of phosphines. Scaling
up of the synthesis yields monodisperse nanoparticles without variations
in their morphology. We have observed the formation of alloyed copper
selenide-sulfide and telluride-sulfide nanocrystals due to the incorporation
of sulfur by using 1-dodecanethiol as a ligand along with oleic acid.
The materials obtained possess localized surface plasmon resonances
in the near-infrared region, which are demonstrated to be widely tunable
via a controlled oxidation generating copper vacancies. Copper sulfide
nanoparticles with well-defined initial chalcocite crystal phase were
subjected to oxidation followed by structural characterization. Structural
rearrangement of the oxidized chalcocite Cu<sub>2–<i>x</i></sub>S crystal lattice to roxbyite by aging is proven to release
the copper vacancies. Further oxidation again can create new copper
vacancies in the roxbyite lattice, however its structure does not
evolve into covellite CuS. These findings suggest that besides nonstoichiometry
(i.e., the value of <i>x</i>) induced by oxidation, crystal
structure is an important factor responsible for plasmonic properties
of copper chalcogenide nanocrystals. Furthermore, successful water
solubilization of Cu<sub>2–<i>x</i></sub>Te<sub><i>y</i></sub>S<sub>1–<i>y</i></sub> nanoparticles
with preservation of their plasmon band has been realized via a ligand
exchange approach employing a mPEG-SH stabilizer