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Elisa Musella Dr. Isacco Gualandi Dr. Erika Scavetta Dr. Massimo Gazzano Arianna Rivalta Dr. Elisabetta Venuti Dr. Meganne Christian Dr. Vittorio Morandi Prof. Dr. Domenica Tonelli 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(71):16301-16310
Layered double hydroxides (LDHs) have been widely studied for their plethora of fascinating features and applications. The potentiostatic electrodeposition of LDHs has been extensively applied in the literature as a fast and direct method to substitute classical chemical routes. However, the electrochemical approach does not usually allow for a fine control of the MII/MIII ratio in the synthesized material. By employing a recently proposed potentiodynamic method, LDH films of controlled composition are herein prepared with good reproducibility, using different ratios of the trivalent (Fe or Al) to bivalent (Co) cations in the electrolytic solution. All the obtained materials are shown to be effective oxygen evolution reaction (OER) catalysts, and are thoroughly characterized by a multi-technique approach, including FE-SEM, XRD, Raman, AES and a wide range of electrochemical procedures. 相似文献
94.
Abstract The physical properties of Pb2+ impurities in the perovskite-like lattice of KMgF3 are very similar to those of (ns)2 ions in alkali halides. The impurity inhomogeneous distribution leads to high dopant levels in the bottom region of the crystals, with a segregation coefficient equal to 0. 020. The optical features of the 336 nm emission support its attribution to luminescence of Pb2+ ions from the relaxed excited B state. 相似文献
95.
96.
Eva Lucaccini Matteo Briganti Dr. Mauro Perfetti Dr. Laure Vendier Dr. Jean‐Pierre Costes Dr. Federico Totti Prof. Dr. Roberta Sessoli Prof. Dr. Lorenzo Sorace 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(16):5552-5562
The magnetic behaviour of a Dy(LH)3 complex (LH? is the anion of 2‐hydroxy‐N′‐[(E)‐(2‐hydroxy‐3‐methoxyphenyl)methylidene]benzhydrazide) was analysed in depth from both theoretical and experimental points of view. Cantilever torque magnetometry indicated that the complex has Ising‐type anisotropy, and provided two possible directions for the easy axis of anisotropy due to the presence of two magnetically non‐equivalent molecules in the crystal. Ab initio calculations confirmed the strong Ising‐type anisotropy and disentangled the two possible orientations. The computed results obtained by using ab initio calculations were then used to rationalise the composite dynamic behaviour observed for both pure DyIII phase and YIII diluted phase, which showed two different relaxation channels in zero and non‐zero static magnetic fields. In particular, we showed that the relaxation behaviour at the higher temperature range can be correctly reproduced by using a master matrix approach, which suggests that Orbach relaxation is occurring through a second excited doublet. 相似文献
97.
Jose Gracia Mauro Fianchini Chiara Biz Victor Polo Roberto Gómez 《Current Opinion in Electrochemistry》2021
Strongly correlated catalysts can be understood from precise quantum approximations. Incorporating properly electronic correlations thus let’s define Spin rules in catalysis, opening a new door towards optimum compositions for the most important reactions for a sustainable future. 相似文献
98.
Computational Management Science - In this paper, we consider a random vector $$X=\left( X_1,X_2\right) $$ following a multivariate Skew Normal distribution and we provide an explicit formula for... 相似文献
99.
100.
Ganesh Narayanan Yavuz Caydamli Halil Tekinalp Ishita Matai Ramiz Boy Ching-Chang Chung Jialong Shen Bhupender S. Gupta Alan E. Tonelli 《Journal of polymer science. Part A, Polymer chemistry》2018,56(22):1529-1537
Three pseudorotaxanes (PpR) comprised of poly (ε-caprolactone) (PCL) and α-cyclodextrin (α-CD) with varying stoichiometric ratios were synthesized and characterized. Wide-angle X-ray diffraction (WAXD) and thermogravimetric (TGA) analyses provided conclusive evidence for complexation between the guest PCL and host α-CD. The as-synthesized and characterized PpRs were used at 10 and 20% concentrations as nucleants to promote the bulk PCL crystallization in composite films. Both WAXD and TGA provided evidence for intact PpR structures in the composite films. Isothermal differential scanning calorimetric (I-DSC) analyses, performed at various crystallization temperatures demonstrated significant differences in the crystallization patterns among the composite films. In addition, I-DSC analyses showed higher Avrami constant values (n) in the PpR-nucleated composite PCL films (n ~ 3), indicating 3-dimensional crystal growth. In the case of neat PCL films, however, lower n values indicated crystal growth in 1-dimensions or 2-dimensions. Moreover, atomic force microscopic analyses showed large crests and pits in PpR-nucleated PCL composites, with irregular morphologies leading to higher surface roughness. To the contrary, the crests and pits were much smaller in the neat PCL films, resulting in lower surface roughness values. Finally, mechanical testing revealed higher tensile strength for PpR-nucleated PCL composites films, demonstrating larger load bearing capabilities. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018 , 56, 1529–1537 相似文献