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Synthesis of Core@Shell Cu-Ni@Pt-Cu Nano-Octahedra and Their Improved MOR Activity

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Angewandte Chemie 2021年第14期133卷

作者： Can Li Xiaobo Chen Dr. Lihua Zhang Dr. Shaohui Yan Dr. Anju Sharma Dr. Bo Zhao Dr. Amar Kumbhar Prof. Dr. Guangwen Zhou Prof. Dr. Jiye Fang Department of Chemistry State University of New York at Binghamton Binghamton NY 13902 USA Materials Science and Engineering Program State University of New York at Binghamton Binghamton NY 13902 USA Center for Functional Nanomaterials Brookhaven National Laboratory Upton NY 11973 USA Present address: College of Environmental Science and Engineering Taiyuan University of Technology Taiyuan Shanxi Province China Analytical and Diagnostics Lab State University of New York at Binghamton Binghamton NY 13902 USA College of Arts & Sciences Microscopy Texas Tech University Lubbock TX 79409 USA Chapel Hill Analytical and Nanofabrication Laboratory University of North Carolina at Chapel Hill Chapel Hill NC 27599 USA

Fabrication of 3 d metal-based core@shell nanocatalysts with engineered Pt-surfaces provides an effective approach for improving the catalytic performance. The challenges in such preparation include shape control of the 3 d metallic cores and thickness control of the Pt-based shells. Herein, we report a colloidal seed-mediated method to prepare octahedral CuNi@Pt-Cu core@shell nanocrystals using CuNi octahedral cores as the template. By precisely controlling the synthesis conditions including the deposition rate and diffusion rate of the shell-formation through tuning the capping ligand, reaction temperature, and heating rate, uniform Pt-based shells can be achieved with a thickness of <1 nm. The resultant carbon-supported CuNi@Pt-Cu core@shell nano-octahedra showed superior activity in electrochemical methanol oxidation reaction (MOR) compared with the commercial Pt/C catalysts and carbon-supported CuNi@Pt-Cu nano-polyhedron counterparts.

关键词： core@shell CuNi@Pt-Cu MOR activity nanocatalysts nano-octahedra

Electron-Ion Collider in China

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arXiv 2021年

作者： Anderle, Daniele P. Bertone, Valerio Cao, Xu Chang, Lei Chang, Ningbo Chen, Gu Chen, Xurong Chen, Zhuojun Cui, Zhufang Dai, Lingyun Deng, Weitian Ding, Minghui Feng, Xu Gong, Chang Gui, Longcheng Guo, Feng-Kun Han, Chengdong He, Jun Hou, Tie-Jiun Huang, Hongxia Huang, Yin Kumerički, Krešimir Kaptari, L.P. Li, Demin Li, Hengne Li, Minxiang Li, Xueqian Liang, Yutie Liang, Zuotang Liu, Chen Liu, Chuan Liu, Guoming Liu, Jie Liu, Liuming Liu, Xiang Liu, Tianbo Luo, Xiaofeng Lyu, Zhun Ma, Boqiang Ma, Fu Ma, Jianping Ma, Yugang Mao, Lijun Mezrag, Cédric Moutarde, Hervé Ping, Jialun Qin, Sixue Ren, Hang Roberts, Craig D. Rojo, Juan Shen, Guodong Shi, Chao Song, Qintao Sun, Hao Sznajder, Pawel Wang, Enke Wang, Fan Wang, Qian Wang, Rong Wang, Ruiru Wang, Taofeng Wang, Wei Wang, Xiaoyu Wang, Xiaoyun Wu, Jiajun Wu, Xinggang Xia, Lei Xiao, Bowen Xiao, Guoqing Xie, Ju-Jun Xie, Yaping H., Xing H., Xu N., Xu S., Xu M., Yan W., Yan W., Yan X., Yan J., Yang Y.-B., Yang Z., Yang D., Yao P., Yin C.-P., Yuan W., Zhan J., Zhang J., Zhang P., Zhang C.-H., Chang Z., Zhang H., Zhao K.-T., Chao Q., Zhao Y., Zhao Z., Zhao L., Zheng J., Zhou X., Zhou X., Zhou B., Zou L., Zou Guangdong Provincial Key Laboratory of Nuclear Science Institute of Quantum Matter South China Normal University Guangzhou510006 China IRFU CEA Université Paris-Saclay Gif-sur-YvetteF-91191 France Institute of Modern Physics Chinese Academy of Sciences Lanzhou730000 China University of Chinese Academy of Sciences Beijing100049 China Nankai University Tianjin300071 China Xinyang Normal University Xinyang464000 China School of Physics and Materials Science Guangzhou University Guangzhou510006 China Hunan University Changsha410082 China Nanjing University Nanjing210093 China Huazhong University of Science and Technology Wuhan430074 China Fondazione Bruno Kessler Villa Tambosi Strada delle Tabarelle 286 VillazzanoTNI-38123 Italy School of Physics Peking University Beijing100871 China Hunan Normal University Changsha410081 China Institute of Theoretical Physics Chinese Academy of Sciences Beijing100190 China Nanjing normal university Nanjing210023 China Department of Physics College of Sciences Northeastern University Shenyang110819 China Southwest Jiaotong University Chengdu610000 China Department of Physics Faculty of Science University of Zagreb Bijenička c. 32 Zagreb10000 Croatia Bogoliubov Laboratory of Theoretical Physics Joint Institute for Nuclear Research Dubna141980 Russia School of Physics and Microelectronics Zhengzhou University Zhengzhou450001 China Lanzhou university Lanzhou730000 China Shandong University Qingdao266237 China Institute of Particle Physics Central China Normal University Wuhan430079 China School of Physics Southeast University Nanjing211189 China Institute of Modern Physics Fudan University Shanghai200433 China Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai201800 China Department of Physics Chongqing University Chongqing401331 China Department of Physics and Astronomy Vrije Universiteit Amsterdam De Boelelaan 1081 Amsterdam1081HV Netherlands Nik

Lepton scattering is an established ideal tool for studying inner structure of small particles such as nucleons as well as nuclei. As a future high energy nuclear physics project, an Electron-ion collider in China (EicC) has been proposed. It will be constructed based on an upgraded heavy-ion accelerator, High Intensity heavy-ion Accelerator Facility (HIAF) which is currently under construction, together with a new electron ring. The proposed collider will provide highly polarized electrons (with a polarization of ∼80%) and protons (with a polarization of ∼70%) with variable center of mass energies from 15 to 20 GeV and the luminosity of (2-3) × 1033 cm−2 s−1. Polarized deuterons and Helium-3, as well as unpolarized ion beams from Carbon to Uranium, will be also available at the EicC. The main foci of the EicC will be precision measurements of the structure of the nucleon in the sea quark region, including 3D tomography of nucleon;the partonic structure of nuclei and the parton interaction with the nuclear environment;the exotic states, especially those with heavy flavor quark contents. In addition, issues fundamental to understanding the origin of mass could be addressed by measurements of heavy quarkonia near-threshold production at the EicC. In order to achieve the above-mentioned physics goals, a hermetical detector system will be constructed with cutting-edge technologies. This document is the result of collective contributions and valuable inputs from experts across the globe. The EicC physics program complements the ongoing scientific programs at the Jefferson Laboratory and the future EIC project in the United States. The success of this project will also advance both nuclear and particle physics as well as accelerator and detector technology in China. © 2021, CC BY.

关键词： Polarization

Effect of pH on the Crystal Growth of ZnO Nanomaterials and Their Band gap Energies 6

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Effect of pH on the Crystal Growth of ZnO Nanomaterials and ...

6th International Conference of Solid State science and Technology and Workshop on Advanced materials Technology: Growth and Characterization, ICSSST AMTGC 2017

作者： Kasim, M.F. Kamarulzaman, N. Rusdi, R. Rahman, A.A. Centre for Nanomaterials Research Institute of Science Level 3 Old Engineering Building Universiti Teknologi MARA Selangor Shah Alam40450 Malaysia School of Physics and Materials Studies Faculty of Applied Sciences Universiti Teknologi MARA Selangor Shah Alam40450 Malaysia School of Chemistry and Environment Faculty of Applied Sciences Universiti Teknologi MARA Selangor Shah Alam40450 Malaysia Centre for Science Foundation Studies Univesity of Malaya Kuala Lumpur50603 Malaysia

Zinc oxide nanostructures with vary pH have been successfully synthesize using a sol-gel method. The nanostructured materials were annealed at low temperature of 300 °C for 3 hour. The effect of pH of the synthesis condition of ZnO on the structural and optical properties of the nanostructures were studied using X-ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM) and UV-Vis spectrophotometer. XRD results revealed that only sample at very acidic condition was not pure with the presence of impurities. This implies that acidic condition require more energy in order to produce pure and single phase of ZnO nanostructures. FESEM results showed that at very acidic and basic condition, the crystallites tended to agglomerate to form bigger particles. The band gap energy of the ZnO nanostructures at pH 6 and 9 were 3.276 and 3.300 eV respectively. Interestingly, it was found that as the aspect ratio of nanorods increased, the band gap energy of the material also increased. © Published under licence by IOP Publishing Ltd.

关键词： X ray diffraction

Search for Gamma-Ray Spectral Lines from Dark Matter Annihilation up to 100 TeV toward the Galactic Center with MAGIC

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Physical Review Letters 2023年第6期130卷 061002-061002页

作者： H. Abe S. Abe V. A. Acciari T. Aniello S. Ansoldi L. A. Antonelli A. Arbet Engels C. Arcaro M. Artero K. Asano D. Baack A. Babić A. Baquero U. Barres de Almeida J. A. Barrio I. Batković J. Baxter J. Becerra González W. Bednarek E. Bernardini M. Bernardos A. Berti J. Besenrieder W. Bhattacharyya C. Bigongiari A. Biland O. Blanch G. Bonnoli Ž. Bošnjak I. Burelli G. Busetto R. Carosi M. Carretero-Castrillo G. Ceribella Y. Chai A. Chilingarian S. Cikota E. Colombo J. L. Contreras J. Cortina S. Covino G. D’Amico V. D’Elia P. Da Vela F. Dazzi A. De Angelis B. De Lotto A. Del Popolo M. Delfino J. Delgado C. Delgado Mendez D. Depaoli F. Di Pierro L. Di Venere E. Do Souto Espiñeira D. Dominis Prester A. Donini D. Dorner M. Doro D. Elsaesser G. Emery V. Fallah Ramazani L. Fariña A. Fattorini L. Font C. Fruck S. Fukami Y. Fukazawa R. J. García López M. Garczarczyk S. Gasparyan M. Gaug J. G. Giesbrecht Paiva N. Giglietto F. Giordano P. Gliwny N. Godinović J. G. Green D. Green D. Hadasch A. Hahn T. Hassan L. Heckmann J. Herrera D. Hrupec M. Hütten R. Imazawa T. Inada R. Iotov K. Ishio I. Jiménez Martínez J. Jormanainen D. Kerszberg Y. Kobayashi H. Kubo J. Kushida A. Lamastra D. Lelas F. Leone E. Lindfors L. Linhoff S. Lombardi F. Longo R. López-Coto M. López-Moya A. López-Oramas S. Loporchio A. Lorini E. Lyard B. Machado de Oliveira Fraga P. Majumdar M. Makariev G. Maneva N. Mang M. Manganaro S. Mangano K. Mannheim M. Mariotti M. Martínez A. Mas Aguilar D. Mazin S. Menchiari S. Mender S. Mićanović D. Miceli T. Miener J. M. Miranda R. Mirzoyan E. Molina H. A. Mondal A. Moralejo D. Morcuende V. Moreno T. Nakamori C. Nanci L. Nava V. Neustroev M. Nievas Rosillo C. Nigro K. Nilsson K. Nishijima T. Njoh Ekoume K. Noda S. Nozaki Y. Ohtani T. Oka J. Otero-Santos S. Paiano M. Palatiello D. Paneque R. Paoletti J. M. Paredes L. Pavletić M. Persic M. Pihet F. Podobnik P. G. Prada Moroni E. Prandini G. Principe C. Priyadarshi I. Puljak W. Rhode M. Ribó J. Rico C. Righi A. Rugliancich N. Sahakyan T. Saito S. Sakurai K. Satalecka F. G. Sat Japanese MAGIC Group: Institute for Cosmic Ray Research (ICRR) The University of Tokyo Kashiwa 277-8582 Chiba Japan Instituto de Astrofísica de Canarias and Departamento de Astrofísica Universidad de La Laguna E-38200 La Laguna Tenerife Spain National Institute for Astrophysics (INAF) I-00136 Rome Italy Università di Udine and INFN Trieste I-33100 Udine Italy Max-Planck-Institut für Physik D-80805 München Germany Università di Padova and INFN I-35131 Padova Italy Institut de Física d’Altes Energies (IFAE) The Barcelona Institute of Science and Technology (BIST) E-08193 Bellaterra (Barcelona) Spain Technische Universität Dortmund D-44221 Dortmund Germany Croatian MAGIC Group: University of Zagreb Faculty of Electrical Engineering and Computing (FER) 10000 Zagreb Croatia IPARCOS Institute and EMFTEL Department Universidad Complutense de Madrid E-28040 Madrid Spain Centro Brasileiro de Pesquisas Físicas (CBPF) 22290-180 URCA Rio de Janeiro (RJ) Brazil University of Lodz Faculty of Physics and Applied Informatics Department of Astrophysics 90-236 Lodz Poland Instituto de Astrofísica de Andalucía-CSIC Glorieta de la Astronomía s/n 18008 Granada Spain Deutsches Elektronen-Synchrotron (DESY) D-15738 Zeuthen Germany ETH Zürich CH-8093 Zürich Switzerland Università di Pisa and INFN Pisa I-56126 Pisa Italy Universitat de Barcelona ICCUB IEEC-UB E-08028 Barcelona Spain Armenian MAGIC Group: A. Alikhanyan National Science Laboratory 0036 Yerevan Armenia Centro de Investigaciones Energéticas Medioambientales y Tecnológicas E-28040 Madrid Spain Department for Physics and Technology University of Bergen Norway INFN MAGIC Group: INFN Sezione di Catania and Dipartimento di Fisica e Astronomia University of Catania I-95123 Catania Italy INFN MAGIC Group: INFN Sezione di Torino and Università degli Studi di Torino I-10125 Torino Italy INFN MAGIC Group: INFN Sezione di Bari and Dipartimento Interateneo di Fisica dell’Università e del Politecnico di Bari I-70125 Bari Italy

Linelike features in TeV γ rays constitute a “smoking gun” for TeV-scale particle dark matter and new physics. Probing the Galactic Center region with ground-based Cherenkov telescopes enables the search for TeV spectral features in immediate association with a dense dark matter reservoir at a sensitivity out of reach for satellite γ-ray detectors, and direct detection and collider experiments. We report on 223 hours of observations of the Galactic Center region with the MAGIC stereoscopic telescope system reaching γ-ray energies up to 100 TeV. We improved the sensitivity to spectral lines at high energies using large-zenith-angle observations and a novel background modeling method within a maximum-likelihood analysis in the energy domain. No linelike spectral feature is found in our analysis. Therefore, we constrain the cross section for dark matter annihilation into two photons to ⟨σv⟩≲5×10−28 cm3 s−1 at 1 TeV and ⟨σv⟩≲1×10−25 cm3 s−1 at 100 TeV, achieving the best limits to date for a dark matter mass above 20 TeV and a cuspy dark matter profile at the Galactic Center. Finally, we use the derived limits for both cuspy and cored dark matter profiles to constrain supersymmetric wino models.

关键词： Dark matter Gamma ray astronomy Particle dark matter Milky Way Cosmic ray & astroparticle detectors Cosmic rays & astroparticles Electromagnetic radiation astronomy Telescopes

Strong chemisorption of CO2 on B10-B13 planar-type clusters

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arXiv 2019年

作者： Santos-Putungan, Alexandra B. Stojić, Nataša Binggeli, Nadia Paraan, Francis N.C. Materials Science and Engineering Program University of the Philippines Diliman Quezon City Philippines Institute of Mathematical Sciences and Physics University of the Philippines Los Baños College Los Baños Laguna Philippines Abdus Salam International Centre for Theoretical Physics Trieste Italy National Institute of Physics University of the Philippines Diliman Quezon City Philippines

An ab initio density functional study was performed investigating the adsorption of CO2 on the neutral boron Bn (n = 10 − 13) clusters, characterized by planar and quasiplanar ground-state atomic structures. For all four clusters, we found strong chemisorption energy of CO2 reaching 1.6 eV for B12 at the cluster edge sites with the adsorbed molecule in the plane of the cluster. A configuration with chemisorbed dissociated CO2 molecule also exists for B11 and B13 clusters. The strong adsorption is due to the bending of the CO2 molecule, which provides energetically accessible fully in-plane frontier molecular orbitals matching the edge states of the clusters. At the same time, the intrinsic dipole moment of a bent CO2 molecule facilitates the transfer of excess electronic charge from the cluster edges to the molecule. Copyright © 2019, The Authors. All rights reserved.

关键词： Carbon dioxide

Application of nanocatalyst iron oxide (Fe2O3) to reduce exhaust emissions (CO and HC) 1

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Application of nanocatalyst iron oxide (Fe2O3) to reduce exh...

1st materials Research Society-Indonesia Conference and Congress 2017, MRS-INA C and C 2017

作者： Puspitasari, P. Yazirin, C. Bachtiar, L.A. Dika, J.W. Zaharis, S.M.S.N.S. Mechanical Engineering Department Engineering Faculty Malang State University Semarang street 5 East-Java-Malang Indonesia Center of Nano Research and Advanced Materials Malang State University Semarang street 5 East-Java-Malang Indonesia Master Program of Mechanical Engineering Engineering Faculty Malang State University Semarang street 5 East-Java-Malang Indonesia Bachelor Program Mechanical Engineering Department Malang State University Semarang street 5 East-Java-Malang Indonesia Industrial Chemical Technology Programme Faculty of Science and Technology Universiti Sains Islam Malaysia Bandar Baru Nilai Negeri Sembilan Nilai71800 Malaysia

Fe2O3 has been the interest of many studies due to its applications in various scientific and industrial fields including in environment, corrosion, soil science, and exhaust emissions. Fe2O3 is a chemical mixture that can be applied as a catalyst to reduce exhaust emissions because it is capable of binding CO and HC contained in motorcycle exhaust gases The growth of motor vehicles results in air pollution and an increase in exhaust emissions consisting of 70.50% CO and 18.34% HC. One effort to reduce exhaust emission levels is by applying a catalytic converter to the exhaust system. This research was an experimental research aiming to investigate the difference in emission level of CO and HC between a motorcycle with and without a catalytic converter. The types of fuel used were RON 88, RON 90, RON 92, and RON 98. The results showed that the application of Fe2O3 as a catalyst could reduce the level of CO significantly in RON 88, i.e. 91.43% CO, and the level of HC in RON 88 and RON 92, i.e. 53.27% and 91.07% HC respectively. © Published under licence by IOP Publishing Ltd.

关键词： Catalytic converters

Influence of scanning parameters on X-ray diffraction peaks of copper 9th

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Influence of scanning parameters on X-ray diffraction peaks ...

9th International Conference on materials science and Technology, MSAT 2016

作者： Chakartnarodom, Parinya Kongkajun, Nuntaporn Laitila, Edward A. Department of Materials Engineering Faculty of Engineering Kasetsart University Chatuchak Bangkok10900 Thailand Materials Science Program Faculty of Science and Technology Thammasat University Klong Luang Prathumthani12121 Thailand Department of Materials Science and Engineering Michigan Technological University HoughtonMI49931 United States Materials Innovation Center Faculty of Engineering Kasetsart University Chatuchak Bangkok10900 Thailand

ISBN: (纸本)9783035710823

The aim of this work is to study the influence of x-ray diffractometer scanning parameters on the integrated intensity and full-width at half maximum (FWHM) of copper powder x-ray diffraction peaks by using statistical analysis methods. X-ray diffraction (XRD) analysis of the copper powder was accomplished using step scan mode with step sizes of 0.03o and 0.05o 2 and preset time changes from 0.1-3.5 s. Integrated intensity of an x-ray peak was calculated by the numerical method. FWHM was measured as the width of Pearson VII model of the x-ray peak at the half-maximum intensity. The statistical analysis methods including linear regression and statistical hypothesis test were used to analyze the correlation between the preset time and the error on integrated intensity calculation, and the FWHM of a peak on the XRD pattern. The results from statistical analysis show that increasing the preset time from 0.1 s to 3.5 s does not affect the FWHM of an x-ray peak, but it reduces the relative error in integrated intensity calculation. Moreover, using the preset time greater than 1 s will minimize the relative error in integrated intensity calculation of an x-ray peak. While step size did not affect both the relative error in integrated intensity calculation or FWHM, the smaller step size would provide more data points for better accurate model of an x-ray peak. © 2017 Trans Tech Publications, Switzerland.

关键词： X ray diffraction analysis

Selective capture of CO2 over N2 and CH4: B clusters and their size effects

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arXiv 2019年

作者： Santos-Putungan, Alexandra B. Stojić, Nataša Binggeli, Nadia Paraan, Francis N.C. Institute of Mathematical Sciences and Physics University of the Philippines Los Baños College Los Baños Laguna Philippines Materials Science and Engineering Program University of the Philippines Diliman Quezon City Philippines Abdus Salam International Centre for Theoretical Physics Trieste Italy National Institute of Physics University of the Philippines Diliman Quezon City Philippines

Using density-functional theory (DFT), we investigate the selectivity of adsorption of CO2 over N2 and CH4 on planar-type B clusters, based on our previous finding of strong chemisorption of CO2 on the B10−13 planar and quasiplanar clusters. We consider the prototype B8 and B12 planar-type clusters and perform a comparative study of the adsorption of the three molecules on these clusters. We find that, at room temperature, CO2 can be separated from N2 by selective binding to the B12 cluster and not to the B8 cluster. Selective adsorption of CO2 over CH4 at room temperature is possible for both clusters. Based on our DFT-adsorption data (including also a semi-infinite Boron sheet) and the available literature-adsorption value for N2 on the planar-type B36 cluster, we discuss the selectivity trend of CO2 adsorption over N2 and CH4 with planar-cluster size, showing that it extends over sizes including B10−13 clusters and significantly larger. Copyright © 2019, The Authors. All rights reserved.

关键词： Density functional theory

Carbon nanotubes from large-scale dft calculations

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arXiv 2018年

作者： Pari, Sangavi Cuellar, Abigail Wong, Bryan M. Department of Chemical Environmental Engineering and Materials Science Engineering Program University of California-Riverside RiversideCA92521 United States Rialto High School RialtoCA92376 United States

Using large-scale DFT calculations, we have investigated the structural and electronic properties of both armchair and zigzag graphdiyne nanotubes as a function of size. To provide insight in these properties, we present new detailed calculations of the structural relaxation energy, effective electron/hole mass, and size-scaling of the bandgap as a function of size and chirality using accurate screened-exchange DFT calculations. These calculations provide a systematic evaluation of the structural and electronic properties of the largest graphdiyne nanotubes to date up to 1,296 atoms and 23,328 basis functions. Our calculations find that zigzag graphdiyne nanotubes (GDNTs) are structurally more stable compared to armchair GDNTs of the same size. Furthermore, these large-scale calculations allow us to present simple analytical formulae to guide future experimental efforts for estimating the fundamental bandgaps of these unique nanotubes as a function of chirality and diameter. While the bandgaps for both the armchair and zigzag GDNTs can be tuned as a function of size, the conductivity in each of these two different chiralities is markedly different. Zigzag GDNTs have wider valence and conduction bands and are expected to have a higher electron-and hole-mobility than their armchair counterparts. Copyright © 2018, The Authors. All rights reserved.

关键词： Nanotubes