Negative ion formation in the three perfluoroethers (PFEs) diglyme (C(6)F(14)O(3)), triglyme (C(8)F(18)O(4)) and crownether (C(10)F(20)O(5)) is studied following electron attachment in the range from ∼0 to 15 eV. All three compounds show intense low energy resonances at subexcitation energies (<3 eV) decomposing into a variety of negatively charged fragments. These fragment ions are generated via dissociative electron attachment (DEA), partly originating from sequential decompositions on the metastable (μs) time scale as observed from the MIKE (metastable induced kinetic energy) scans. Only in perfluorocrownether a signal due to the non-decomposed parent anion is observed. Additional and comparatively weaker resonances are located in the energy range between ∼10 and 17 eV which preferentially decompose into lighter ions. It is suggested that specific features of perfluoropolyethers (PFPEs) relevant in applications, e.g., the strong bonding to surfaces induced by UV radiation of the substrate or degradation of PFPE films in computer hard disc drives can be explained by their pronounced sensitivity towards low energy electrons.
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http://dx.doi.org/10.1016/j.ijms.2011.06.018 | DOI Listing |
Chem Soc Rev
January 2025
National-local Joint Engineering Research Center of Biomass Refining and High-quality Utilization, Changzhou University, Changzhou 213164, China.
Multiple oxygenate groups in biomass-based feedstocks are open to multiple catalytic pathways and products, typically resulting in low selectivity for the desired products. In this context, strategies for rational catalyst design are critical to obtain high selectivity for the desired products in biomass upgrading. The Sabatier principle provides a conceptual framework for designing optimal catalysts by following the volcanic relationship between catalyst activity for a reaction and the binding strength of a substrate on a catalyst.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
Ruhr-Universität Bochum: Ruhr-Universitat Bochum, Inorganic Chemistry, Universitaetsstrasse 150, 44801, Bochum, GERMANY.
Precise control over low-dimensional materials holds an immense potential for their applications in sensing, imaging and information processing. The controlled introduction of sp3 quantum defects (color centers) can be used to tailor the optoelectronic properties of single-walled carbon nanotubes (SWCNTs) in the tissue transparency (> 800 nm) and the telecommunication window. However, an uncontrolled functionalization of SWCNTs with defects leads to a loss of the NIR fluorescence.
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
January 2025
Department of Chemistry, Utkal University, Bhubaneswar, 751 004, Odisha, India.
This research highlights a sustainable approach for the design and synthesis of a magnetic nickel ferrite (NiFeO) catalyst reutilizing industrial waste, specifically iron ore tailing and Raney nickel catalyst processing waste, by simple co-precipitation method. Transforming waste materials into high-performance catalysts, this study aligns with the principles of a circular economy, addressing both environmental waste and pollution. Structural characterization by X-ray diffraction (XRD) and microscopic (FESEM and TEM) revealed the formation of well crystalline nano ferrite with NiFeO nanoparticles with cubic spinel structure.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Tianjin Key Laboratory for Marine Environmental Research and Service, School of Marine Science and Technology, Tianjin University, Tianjin 300072, China.
Marine biofouling and corrosion have become the main problems affecting the development of the marine industry. Silicone-based coatings have been widely used for antifouling and anticorrosion due to their low surface energy. However, the poor adhesion and low mechanical stability of these materials limit their application in complex marine environments.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
January 2025
Department of Aquatic Ecology, Netherlands Institute of Ecology, Wageningen 6708 PB, The Netherlands.
Arctic ecosystems are affected by accelerated warming as well as the intensification of the hydrologic cycle, yet understanding of the impacts of compound climate extremes (e.g., simultaneous extreme heat and rainfall) remains limited, despite their high potential to alter ecosystems.
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