Hydrophobic cluster structures in aqueous ethanol solutions at different concentrations have been investigated by soft X-ray absorption spectroscopy (XAS). In the O K-edge XAS, we have found that hydrogen bond structures among water molecules are enhanced in the middle-concentration region by the hydrophobic interaction of the ethyl groups in ethanol. In the C K-edge XAS, the lower energy features arise from a transition from the terminal methyl C 1s electron to an unoccupied orbital of 3s Rydberg character, which is sensitive to the nearest-neighbor intermolecular interactions. From the comparison of C K-edge XAS with the inner-shell calculations, we have found that ethanol clusters are easily formed in the middle-concentration region due to the hydrophobic interaction of the ethyl group in ethanol, resulting in the enhancement of the hydrogen bond structures among water molecules. This behavior is different from aqueous methanol solutions, where the methanol-water mixed clusters are more predominant in the middle-concentration region due to the relatively weak hydrophobic interactions of the methyl group in methanol.
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http://dx.doi.org/10.1021/acs.jpcb.2c02990 | DOI Listing |
J Environ Manage
January 2025
Department of Agricultural Chemistry, National Taiwan University, Taipei, 106319, Taiwan. Electronic address:
Molybdenum (Mo) is an essential micronutrient for plants, yet it also poses potential environmental risks when present in excess. This study investigated the Mo speciation in soils with varying properties and their influences on Mo uptake by wheat (Triticum aestivum L.), a staple crop with significant implications for global food security.
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Department of Interface Science, Fritz-Haber Institute of the Max Planck Society, 14195 Berlin, Germany.
Nickel and nitrogen co-doped carbon (Ni-N-C) catalysts are attracting attention due to their exceptionally high performance in the electrocatalytic reduction of CO_{2}(CO_{2}RR) to CO. However, the direct experimental insight into the working mechanism of these catalysts is missing, hindering our fundamental understanding and their further improvement. This work sheds light on the nature of adsorbates forming under CO_{2}RR at singly dispersed Ni sites.
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November 2024
Department of Materials, Oxford University, Oxford OX1 3PH, U.K.
J Hazard Mater
November 2024
Environmental Geochemistry Laboratory, Department of Earth and Environmental Sciences, Indian Institute of Science Education and Research (IISER) Bhopal, Bhopal Bypass Road, Bhauri 462066, Madhya Pradesh, India; Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BayCEER), University of Bayreuth, 95440 Bayreuth, Germany. Electronic address:
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Institute of Energy: Sustainability, Environment, and Equity, Stony Brook University, Stony Brook, New York 11794, United States.
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