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Single atom Cu-N-C catalysts for the electro-reduction of CO_(2) to CO assessed by rotating ring-disc electrode

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Journal of Energy Chemistry 2024年第1期88卷 169-182,I0004页

作者： S.Pérez-Rodríguez M.Gutiérrez-Roa C.Giménez-Rubio D.Ríos-Ruiz P.Arévalo-Cid M.V.Martínez-Huerta A.Zitolo M.J.Lázaro D.Sebastián Instituto de Carboquímica(CSIC) Miguel Luesma Castán 450018 ZaragozaSpain Instituto de Catálisis y Petroleoquímica(CSIC) Marie Curie 228049 MadridSpain Synchrotron SOLEIL L’Orme des MerisiersDépartementale 12891190France

The electrochemical CO_(2) reduction reaction(CO_(2)RR) to controllable chemicals is considered as a promising pathway to store intermittent renewable energy. Herein, a set of catalysts based on copper-nitrogendoped carbon xerogel(Cu-N-C) are successfully developed varying the copper amount and the nature of the copper precursor, for the efficient CO_(2)RR. The electrocatalytic performance of Cu-N-C materials is assessed by a rotating ring-disc electrode(RRDE), technique still rarely explored for CO_(2)RR. For comparison, products are also characterized by online gas chromatography in a H-cell. The as-synthesized Cu-NC catalysts are found to be active and highly CO selective at low overpotentials(from -0.6 to -0.8 V ***) in 0.1 M KHCO_(3), while H_(2) from the competitive water reduction appears at larger overpotentials(-0.9 V vs. RHE). The optimum copper acetate-derived catalyst containing Cu-N_(4) moieties exhibits a CO_(2)-to-CO turnover frequency of 997 h^(-1) at -0.9 V vs. RHE with a H_(2)/CO ratio of 1.8. These results demonstrate that RRDE configuration can be used as a feasible approach for identifying electrolysis products from CO_(2)RR.

关键词： Cu-N-C Carbon xerogel Rotating ring disc electrode Carbon dioxide reduction reaction Carbon monoxide

Competing magnetic states in silicene and germanene 2D ferromagnets

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Nano Research 2020年第12期13卷 3396-3402页

作者： Dmitry V.Averyanov Ivan S.Sokolov Mikhail S.Platunov Fabrice Wilhelm Andrei Rogalev Pierluigi Gargiani Manuel Valvidares Nicolas Jaouen Oleg E.Parfenov Alexander N.Taldenkov Igor A.Karateev Andrey M.Tokmachev Vyacheslav G.Storchak National Research Center“Kurchatov Institute” Kurchatov Sq.1Moscow123182Russia ESRF-The European Synchrotron CS 4022038043Grenoble Cedex 9France ALBA Synchrotron Light Source Cerdanyola del Vallès08290BarcelonaSpain L’orme des merisiers Synchrotron SOLEILGyf-sur-Yvette91192France

Two-dimension(2D)magnets have recently developed into a class of stoichiometric materials with prospective applications in ultra-compact spintronics and quantum *** functionality is particularly rich when different magnetic orders are competing in the same *** REX2(RE=Eu,Gd;X=Si,Ge),silicene or germanene—heavy counterparts of graphene—coupled with a layer of rare-earth metals,evolve from three-dimension(3D)antiferromagnets in multilayer structures to 2D ferromagnets in a few *** evolution,however,does not lead to fully saturated 2D ferromagnetism,pointing at a possibility of coexisting/competing magnetic ***,REX2 magnetism is explored with element-selective X-ray magnetic circular dichroism(XMCD).The measurements are carried out for GdSi2,EuSi2,GdGe2,and EuGe2 of different thicknesses down to 1 monolayer employing K absorption edges of Si and Ge as well as M and L edges of the *** access the magnetic state in REX2 and determine the seat of magnetism,orbital,and spin contributions to the magnetic ***-field measurements probe remnants of the bulk antiferromagnetism in 2D *** results provide a new platform for studies of complex magnetic structures in 2D materials.

关键词： silicene germanene 2D ferromagnetism X-ray magnetic circular dichroism(XMCD) monolayer

X-ray-induced radiophotodynamic therapy （RPDT） using lanthanide micelles： Beyond depth limitations

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Nano Research 2015年第7期8卷 2373-2379页

作者： Slavka Kascakova Alexandre Giuliani Sara Lacerda Agnes Pallier Pascal Mercere eva Toth Matthieu Refregiers Synchrotron SOLEIL L'Orme des Merisiers 91190 Gif-sur-Yvette France Universite Paris-Sud XI UMR-S I 193 94800 Villejuif France INRA UAR 1008 Caracterisation et elaboration des Produits Issus de I'Agriculture 44316 Nantes France Centre de Biophysique Moleculaire CNRS Rue Charles Sadron 45071 Orleans Cedex 2 France

We report lanthanide-based micelles integrating hypericin （Hyp） for X-ray- triggered photodynamic therapy （PDT）. The lanthanide luminescence induced by X-ray irradiation excites the photosensitizer, which leads to the generation of singlet oxygen. This versatile approach can be extended to other photosensitizers or other types of liponanoparticles and can allow for magnetic resonance imaging （MRI） guidance.

关键词： photodynamic therapy liponanoparticles,x-ray deep tumour photosensitizer

A convolutional neural network for defect classification in Bragg coherent X-ray diffraction

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npj Computational Materials 2021年第1期7卷 1026-1033页

作者： Bruce Lim Ewen Bellec Maxime Dupraz Steven Leake Andrea Resta Alessandro Coati Michael Sprung Ehud Almog Eugen Rabkin Tobias Schulli Marie-Ingrid Richard Grenoble INP-Phelma Univ.Grenoble AlpesGrenobleFrance ESRF-The European Synchrotron GrenobleFrance CEA Grenoble IRIGMEMNRSUniv.Grenoble AlpesGrenobleFrance Synchrotron SOLEIL L’Orme des MerisiersGif-sur-YvetteFrance Deutsches Elektronen-Synchrotron(desY) HamburgGermany Department of Materials Science and Engineering Technion-Israel Institute of TechnologyHaifaIsrael

Coherent diffraction imaging enables the imaging of individual defects,such as dislocations or stacking faults,in *** defects and their surrounding elastic strain fields have a critical influence on the macroscopic properties and functionality of ***,their identification in Bragg coherent diffraction imaging remains a challenge and requires significant data *** ability to identify defects from the diffraction pattern alone would be a significant advantage when targeting specific defect types and accelerates experiment design and ***,we exploit a computational tool based on a three-dimensional(3D)parametric atomistic model and a convolutional neural network to predict dislocations in a crystal from its 3D coherent diffraction *** diffraction patterns from several thousands of relaxed atomistic configurations of nanocrystals are used to train the neural network and to predict the presence or absence of dislocations as well as their type(screw or edge).Our study paves the way for defect-recognition in 3D coherent diffraction patterns for material science.

关键词： materials coherent defect

Operando investigation of nanocrystal-based device energy landscape:Seeing the current pathway

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Nano Research 2024年第12期17卷 10376-10385页

作者： Mariarosa Cavallo Dario Mastrippolito Erwan Bossavit Leonardo Curti Adrien Khalili Huichen Zhang Nicolas Ledos Yoann Prado Erwan Dandeu Michael Rosticher Sandrine Ithurria Pavel Dudin JoséAvila Debora Pierucci Emmanuel Lhuillier Sorbonne Université CNRSInstitut des NanoSciences de Paris4 place Jussieu75005 ParisFrance Laboratoire de Physique et d’Etude des Matériaux ESPCIPSL Research UniversitySorbonne UniversitéCNRS10 rue Vauquelin75005 ParisFrance Laboratoire de physique de l’Ecole Normale Supérieure ENSUniversitéPSLCNRSSorbonne UniversitéUniversitéParis Cité24 Rue Lhomond75005 ParisFrance Synchrotron SOLEIL L’Orme des MerisiersDépartementale 12891190 Saint-AubinFrance

Due to their unique optical properties,colloidal nanocrystals(NCs)have transitioned from a solution processable luminescent liquid to an established building block for *** devices get more advanced,a higher degree of refinement is also required for the probe used to investigate their electronic *** long,device optimization has relied on the measurement of physical properties of the pristine material,assuming that they would be maintained after device ***,such an assumption neglects the realistic dielectric environment and possibly applied electric fields to drive the ***,tools compatible with operando investigation of the electronic structure are ***,we review and present additional results relative to the operando investigation of infrared NCs using photoemission *** technique combines the advantages of photoemission to unveil band alignment with a sub-μm spatial resolution that is used to correlate energy shift to the device *** method gives direct access to parameters such as diode built-in potential,transistor lever arm,or even the vectorial distribution of the electric field that are otherwise only attainable through indirect methods involving *** provide indications and precautions to be used in the design of devices to permit the operando analysis via photoemission *** is,therefore,a very promising tool for the optimization of NC-based devices.

关键词： nanocrystals device photoemission microscopy electric field field effect transistor

Synchrotron microtomography reveals insights into the degradation kinetics of bio-degradable coronary magnesium scaffolds

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Bioactive Materials 2024年第2期32卷 1-11页

作者： Roman Menze Bernhard Hesse Maciej Kusmierczuk Duote Chen Timm Weitkamp Stephanie Bettink Bruno Scheller MeKo Manufacturing e.K. Im Kirchenfelde 12-1431157SarstedtGermany Xploraytion GmbH Bismarckstr.10-1210625BerlinGermany Synchrotron SOLEIL L’Orme des MerisiersDépartementale 12891190Saint-AubinFrance InnoRa GmbH Robert-Koch-Platz 410115BerlinGermany Universität des Saarlandes Campus Homburg66421HomburgGermany

Bioresorbable magnesium scaffolds are a promising future treatment option for coronary artery stenosis,especially for young *** to the degradation of these scaffolds(<1 year),long-term device-related clinical events c... 详细信息

Bioresorbable magnesium scaffolds are a promising future treatment option for coronary artery stenosis,especially for young *** to the degradation of these scaffolds(des of development,the degradation process,ideal degradation time and biological response in vivo are still not fully *** present study investigates the in vivo degradation of magnesium scaffolds in the coronary arteries of pigs influenced by different strut thicknesses and the presence of antiproliferative *** to high 3D image contrast of synchrotron-based micro-CT with phase contrast(SR-μCT),a qualitative and quantitative evaluation of the degradation morphology of magnesium scaffolds was *** the segmentation of theμCT images a convolutional network architecture(U-net)was exploited,demonstrating the huge potential of merging high resolution SR-μCT with deep learning(DL)supported data *** total,30 scaffolds,made of the rare earth alloy Resoloy^(®),with different strut designs were implanted into the coronary arteries of 10 domestic pigs for 28 days using drug-coated or uncoated angioplasty balloons for *** degradation morphology was analyzed using scanning electron microscopy,energy dispersive x-ray spectroscopy and SR-μ*** data from these methods were then related to data from angiography,optical coherence tomography and histology.A thinner strut size(95 vs.130μm)and the presence of paclitaxel indicated a slower degradation rate at 28 d in vivo,which positively influences the late lumen loss(0.5 and 0.6 mm vs.1.0 and 1.1 mm)and recoil values(0 and 1.7%vs.6.1 and 22%).

关键词： Resoloy Magnesium scaffold DCB Paclitaxel Degradation Inflammation Artificial intelligence

Detecting exoplanets with FAST?

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Research in Astronomy and Astrophysics 2019年第2期19卷 71-76页

作者： Philippe Zarka Di Li Jean-Mathias Grie?meier Laurent Lamy Julien N.Girard Sbastien L.G.Hess T.Joseph W.Lazio Gregg Hallinan LESIA CNRS – Observatoire de Paris National Astronomical Observatories Chinese Academy of Science CAS Key Laboratory of FAST National Astronomical Observatories Chinese Academy of Sciences School of Astronomy and Space Science University of Chinese Academy of Sciences LPC2E CNRS – Universit d'Orlans Universit Paris VII AIM/Irfu/SAp/CEA-Saclay Orme des Merisiers ONERA – desP JPL–California Institute of Technology California Institute of Technology

We briefly review the various proposed scenarios that may lead to nonthermal radio emissions from exoplanetary systems(planetary magnetospheres, magnetosphere-ionosphere and magnetospheresatellite coupling, and star-planet interactions), and the physical information that can be drawn from their detection. The latter scenario is especially favorable to the production of radio emission above 70 MHz. We summarize the results of past and recent radio searches, and then discuss FAST characteristics and observation strategy, including synergies. We emphasize the importance of polarization measurements and a high duty-cycle for the very weak targets that radio-exoplanets prove to be.

关键词： plasmas radiation mechanisms:non-thermal methods:observational telescopes(radio) planets and satellites:magnetic fields radio continuum:planetary systems

Huge metastable axial strain in ultrathin heteroepitaxial vertically aligned nanowires

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Nano Research 2015年第6期8卷 1964-1974页

作者： Vivien Schuler Francisco Javier Bonilia Dominique Demaille Alessandro Coati Alina Vlad Yves Garreau Michele Sauvage-Simkin Anastasiia Novikova Emiliano Fonda Sarah Hidki Victor Etgens Franck Vidal Yunlin Zheng Sorbonne Universites UPMC Institut des NonoSciences de Paris 4 place Jussieu Paris 75005 France CNRS UMR7588 Institut des NanoSciences de Paris 4 place Jussieu Paris 75005 France Synchrotron Soleil L'Orme des Merisiers Saint-Aubin BP 48 91192 Gif-sur-Yvette Cedex France Universite Paris Diderot Sorbonne Paris Cite MPO UMR 7162 CNRS Batiment Condorcet Case courrier 7021 75205 Paris Cedex 13 France Universite de Versailles Saint-Quentin en Yvelines 55 Av. de Paris Versailles 78035 France

Strain engineering is a powerful tool to tailor the physical properties of materials coherently stacked in an epitaxial heterostructure. Such an approach, applied to the mature field of planar heteroepitaxy, has yielded a variety of new phenomena and devices. Recently, heteroepitaxial vertically aligned nanocomposites have emerged as alternatives to planar structures. Owing to the peculiar geometry of such nanoarchitectures, efficient strain control can be achieved, opening the way to novel functionalities. In this paper, we report a very large tensile axial strain in epitaxial transition metal nanowires embedded in an oxide matrix. We show that axial strains in excess of 1.5% can be sustained over a large thickness （a few hundred nanometers） in epitaxial nanowires having ultrasmall diameters （-3-6 nm）. The axial strain depends on the diameter of the nanowires, reflecting its epitaxial nature and the balance of interface and elastic energies. Furthermore, it is experimentally shown that such strain is metastable, in agreement with the calculations performed in the framework of the Frenkel-Kontorova model. The diameter dependence and metastability provide effective ways to control the strain, an appealing feature for the design of functional nanoarchitectures.

关键词： self-assembly heteroepitaxy nanowires strain

X-ray microscopic investigation of molecular orientation in a hole carrier thin film for organic solar cells

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Nano Research 2018年第5期11卷 2771-2782页

作者： Quentin Arnoux Benjamin Watts Sufal Swaraj Francois Rochet Ludovic Tortech Laboratoire de Chimie Physique Matiere et Rayonnement (LCPMR) UMR 7614 Sorbonne Universites UPMC Univ Paris 06 Paris F-75005 France Institut Parisien de Chimie Moleculaire (IPCM) UMR 8232 Sorbonne Universites UPMC Univ Paris 06 Paris F-75005 France Laboratoire d'Innovation en Chimie des Surfaces et Nanosciences (LICSEN) NIMBE UMR 3685 CEA Saday Gif-sur-Yvette F-91191 France Paul Scherrer Institute Villigen Psi 5232 Switzerland Synchrotron SOLEIL L'Orme des Merisiers Saint-Aubin BP 48 Gif-sur-Yvette F-91192 France

As dipyranylidenes are excellent hole carriers, applications in organic solar cells or organic light emitting diode are envisaged. In the present study, we investigate the morphology of 2,2＇,6,6＇-tetraphenyl-4,4＇-dipyranylidene （DIPO-Ph4） deposited under vacuum on a silicon nitride （Si3N4） substrate, a paradigmatic system for the study of molecular crystal/inorganic substrate interfaces. Samples with various coating ratios and different thermal treatments were prepared. The films were characterized by atomic force microscopy and scanning transmission X-ray microscopy to gain insight into material growth. The results show a change in orientation at a molecular level depending upon the evaporation conditions. We are now able to tailor an organic layer with a specific molecular orientation and a specific electronic behavior.

关键词： organic solar cells scanning transmission X-ray microscopy molecular orientation inorganic/organic interface