Vessel wall MRI with intravascular (IV) detectors can produce superior local signal-to-noise ratios (SNR) and generate high-resolution T, T, and proton density (PD) maps that could be used to automatically classify atherosclerotic lesion stage. However, long acquisition times potentially limit multi-parametric mapping. Here, for the first time, spectroscopy with linear algebraic modeling (SLAM) is applied to yield accurate compartment-average T, T and PD measures at least 10 times faster compared to a standard full k-space reconstructed MIX-TSE sequence at 3T. Simple phase and magnitude sensitivity corrections are incorporated into the SLAM reconstruction to compensate for IV detector non-uniformity.
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J Am Chem Soc
January 2025
Dipartimento di Scienze Fisiche e Chimiche, Universita degli Studi dellAquila, Coppito, 67100 L'Aquila, Italy.
We present a comprehensive theoretical study, using state-of-the-art density functional theory simulations, of the structural and electrochemical properties of amorphous pristine and iron-doped nickel-(oxy)hydroxide catalyst films for water oxidation in alkaline solutions, referred to as NiCat and Fe:NiCat. Our simulations accurately capture the structural changes in locally ordered units, as reported by X-ray absorption spectroscopy, when the catalyst films are activated by exposure to a positive potential. We emphasize the critical role of proton-coupled electron transfer in the reversible oxidation of Ni(II) to Ni(III/IV) during this activation.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Departament de Ciència de Materials i Química Física & Institut de Química Teòrica i Computacional (IQTCUB), Universitat de Barcelona, c/Martí i Franquès 1-11, Barcelona 08028, Spain.
The oxygen reduction reaction (ORR) stands as a pivotal process in electrochemistry, finding applications in various energy conversion technologies such as fuel cells, metal-air batteries, and chlor-alkali electrolyzers. Hereby, a comprehensive density functional theory (DFT) investigation is presented into the proposed conventional and unconventional ORR mechanisms using single-atom catalysts (SACs) supported on nitrogen-doped graphene (NG) as model systems. Several reaction intermediates have been identified that appear to be more stable than the ones postulated in the conventional mechanism, which follows the *OOH, *O, and *OH intermediates.
View Article and Find Full Text PDFInorg Chem
January 2025
Advanced Institute for Materials Research (WPI-AIMR), Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai 980-8577, Japan.
Sodium borohydride dihydrate (NaBH·2HO) forms through dihydrogen bonding between the hydridic hydrogen of the BH ion and the protonic hydrogen of the water molecule. High-pressure structural changes in NaBH·2HO, observed up to 11 GPa through X-ray diffraction and Raman scattering spectroscopy, were analyzed to assess the influence of dihydrogen bonds on its crystal structure. At approximately 4.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
Although microenvironments surrounding single-atom catalysts (SACs) have been widely demonstrated to have a remarkable effect on their catalytic performances, it remains unclear whether the local structure beyond the secondary coordination shells works as well or not. Herein, we employed a series of metal-organic frameworks (MOFs) with well-defined and tunable second-beyond coordination spheres as model SAC electrocatalysts to discuss the influence of long-distance structure on the ammonia synthesis from nitrate, which were synthesized and denoted as Cu-NDI-X (X = NMe, H, F). It is first experimentally confirmed that the remote substitution of function groups beyond the secondary coordination sphere can remarkably affect the activity of ammonia synthesis.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
Harbin Institute of Technology (Shenzhen), Department of Materials Science and Engineering, College Park, Building C, 404, Shenzhen, CHINA.
Conventional SEI in aqueous Zn-ion batteries mainly acts as a physical barrier to prevent HER, which is prone to structural deterioration stemming from uneven Zn deposition at high current densities. Herein, we propose an in-situ structural design of polymer-inorganic bilayer SEI with a proton holder feature by aniline-modulated electrolytes. The inner ZnF2 with high stiffness and strength effectively suppresses Zn dendrites.
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