共查询到20条相似文献,搜索用时 15 毫秒
1.
2.
3.
4.
5.
6.
7.
8.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2018,130(37):12079-12084
The hydrophobic (HB) interaction plays a critical role in many colloidal and interfacial phenomena, biophysical and industrial processes. Surface hydrophobicity, characterized by the water contact angle, is generally considered the most dominant parameter determining the HB interaction. Herein, we quantified the HB interactions between air bubbles and a series of hydrophobic surfaces with different nanoscale structures and surface chemistry in aqueous media using a bubble probe atomic force microscopy (AFM). Surprisingly, it is discovered that surfaces of similar hydrophobicity can show different ranges of HB interactions, while surfaces of different hydrophobicity can have similar ranges of HB interaction. The increased heterogeneity of the surface nanoscale structure and chemistry can effectively decrease the decay length of HB interaction from 1.60 nm to 0.35 nm. Our work provides insights into the physical mechanism of HB interaction. 相似文献
9.
10.
11.
Xi Yao Stuart S. Dunn Philseok Kim Meredith Duffy Jack Alvarenga Joanna Aizenberg 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(17):4507-4511
Omniphobic fluorogel elastomers were prepared by photocuring perfluorinated acrylates and a perfluoropolyether crosslinker. By tuning either the chemical composition or the temperature that control the crystallinity of the resulting polymer chains, a broad range of optical and mechanical properties of the fluorogel can be achieved. After infusing with fluorinated lubricants, the fluorogels showed excellent resistance to wetting by various liquids and anti‐biofouling behavior, while maintaining cytocompatiblity. 相似文献
12.
13.
14.
Oriol Piqu Iskra Z. Koleva Francesc Vies Hristiyan A. Aleksandrov Georgi N. Vayssilov Francesc Illas 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(6):1758-1762
Carbon moieties on late transition metals are regarded as poisoning agents in heterogeneous catalysis. Recent studies show the promoting catalytic role of subsurface C atoms in Pd surfaces and their existence in Ni and Pt surfaces. Here energetic and kinetic evidence obtained by accurate simulations on surface and nanoparticle models shows that such subsurface C species are a general issue to consider even in coinage noble‐metal systems. Subsurface C is the most stable situation in densely packed (111) surfaces of Cu and Ag, with sinking barriers low enough to be overcome at catalytic working temperatures. Low‐coordinated sites at nanoparticle edges and corners further stabilize them, even in Au, with negligible subsurface sinking barriers. The malleability of low‐coordinated sites is key in the subsurface C accommodation. The incorporation of C species decreases the electron density of the surrounding metal atoms, thus affecting their chemical and catalytic activity. 相似文献
15.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(33):10023-10028
Layered black phosphorus has been attracting great attention due to its interesting material properties which lead to a plethora of proposed applications. Several approaches are demonstrated here for covalent chemical modifications of layered black phosphorus in order to form P−C and P‐O‐C bonds. Nucleophilic reagents are highly effective for chemical modification of black phosphorus. Further derivatization approaches investigated were based on radical reactions. These reagents are not as effective as nucleophilic reagents for the surface covalent modification of black phosphorus. The influence of covalent modification on the electronic structure of black phosphorus was investigated using ab initio calculations. Covalent modification exerts a strong effect on the electronic structure including the change of band‐gap width and spin polarization. 相似文献
16.
Daniel Melzer Pinghong Xu Daniela Hartmann Yuanyuan Zhu Nigel D. Browning Maricruz Sanchez‐Sanchez Johannes A. Lercher 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2016,128(31):9019-9023
Aberration‐corrected high‐angle annular dark‐field scanning transmission electron microscopy (HAADF‐STEM) has been used to image the basal {001} plane of the catalytically relevant M1 phase in MoVTeNb complex oxides. Facets {010}, {120}, and {210} are identified as the most frequent lateral termination planes of the crystals. Combination of STEM with He ion microscopy (HIM) images, Rietveld analysis, and kinetic tests reveals that the activation of ethane is correlated to the availability of facets {001}, {120}, and {210} at the surface of M1 crystals. The lateral facets {120} and {210} expose crystalline positions related to the typical active centers described for propane oxidation. Conversely, the low activity of the facet {010} is attributed to its configuration, consisting of only stable M6O21 units connected by a single octahedron. Thus, we quantitatively demonstrated that differences in catalytic activity among M1 samples of equal chemical composition depend primarily on the morphology of the particles, which determines the predominant terminating facets. 相似文献
17.
18.
19.
20.