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First-principles calculation of the structure and the energy of ZrO_2/Al_2O_3 nanomultilayer

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Science China(Physics,Mechanics & Astronomy) 2011年第11期54卷 1990-1999页

作者： GAO Xue ZHANG Yue shang jiaxiang School of Materials Science and Engineering Beijing University of Aeronautics and Astronautics Beijing 100083 China

The electronic structure, atomic geometry and energetic properties of ceramic nanomultilayer have been systematically studied with first principles density functional theory calculations based on the generalized gradient approximations. It is found that the interface structure and adhesion, which determine the mechanical and thermal properties, are sensitive to the surface mor- phology. We also provide an analysis of adhesion of ZrO2/A1203 interface as a function of thickness of each layer. With the in- crease of ZrO2 thickness, both covalence and ionicity of the interfacial bonds are enhanced, which results in more strongly coupled interfaces while the ionic interaction decreases for thicker Al2O3 layers, which results in weakly coupled interfaces. A first-principles calculation method has been proposed to design nanomultilayer materials to achieve the demanded adhesion.

关键词： nanomultilayer first principles interface

High-throughput screening of carbon-supported single metal atom catalysts for oxygen reduction reaction

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Nano Research 2022年第2期15卷 1054-1060页

作者： Yiran Wang Riming Hu Yongcheng Li Fuhe Wang jiaxiang shang Jianglan Shui School of Materials Science and Engineering Beihang UniversityBeijing 100191China Qinghai Provincial Key Laboratory of New Light Alloys Qinghai Provincial Engineering Research Center of High-Performance Light Metal Alloys and FormingQinghai UniversityXining 810016China Center for Condensed Matter Physics Department of Physics Capital Normal UniversityBeijing 100048China

Carbon-supported transition metal single atoms are promising oxygen reduction reaction(ORR)*** there are many types of carbon supports and transition metals,the accurate prediction of the components with high activity through theoretical calculations can greatly save experimental time and *** this work,the ORR catalytic properties of 180 types single-atom catalysts(SACs)composed of the eight representative carbon-based substrates(graphdiyne,C_(2)N,C_(3)N_(4),phthalocyanine,C-coordination graphene,N-coordination graphene,covalent organic frameworks and metal-organic frameworks)and 3d,4d,and 5d transition metal elements are investigated by density functional theory(DFT).The adsorption free energy of OH^(*) is proved a universal descriptor capable of accurately prediction of the ORR catalytic *** is found that the oxygen reduction reaction overpotentials of all the researched SACs follow one volcano shape very well with the adsorption free energy of OH^(*).Phthalocyanine,N-coordination graphene and metal-organic frameworks stand out as the promising supports for single metal atom due to the relatively lower ***,the Co-doped metal-organic frameworks,Ir-doped phthalocyanine,Co-doped N-coordination graphene,Co-doped graphdiyne and Rh-doped phthalocyanine show extremely low overpotentials comparable to that of Pt(111).The study provides a guideline for design and selection of carbon-supported SACs toward oxygen reduction reaction.

关键词： oxygen reduction reaction carbon-supported catalysts high throughput screening density functional theory single-atom catalysts

Rational design of bimetallic atoms supported on C3N monolayer to break the linear relations for efficient electrochemical nitrogen reduction

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Nano Research 2022年第9期15卷 8656-8664页

作者： Riming Hu Yanan Yu Yongcheng Li Yiran Wang jiaxiang shang Yong Nie Xuchuan Jiang Institute for Smart Materials&Engineering University of JinanJinan 250022China Shandong college of Tourism and Hospitality Jinan 250200China Qinghai Provincial Key Laboratory of New Light Alloys Qinghai Provincial Engineering Research Center of High-Performance Light Metal Alloys and FormingQinghai UniversityXining 810016China School of Materials Science and Engineering Beihang UniversityBeijing 100191China

Linear relations between the adsorption free energies of nitrogen reduction reaction(NRR)intermediates limit the catalytic activity of single atom catalysts(SACs)to reach the optimal *** improvements in NRR activity require the balance of binding strength of reaction ***,we have investigated the C_(3)N-supported monometallic(M/C_(3)N)and bimetallic(M_(1)M_(2)/C_(3)N)atoms for the electrochemical NRR by using density functional theory(DFT)*** results show that this linear relation does exist for SACs because all the intermediates bind to the same site on M/C_(3)*** the synergistic effect of the two atoms in M_(1)M_(2)/C_(3)N can create a more flexible adsorption site for intermediates,which results in the decoupling of adsorption free energies of key ***,the fundamental limitation of scaling relations on limiting potentials is broken *** notably,the optimal limiting potential is increased from−0.63 V for M/C_(3)N to−0.20 V for M_(1)M_(2)/C_(3)*** addition,the presence of bimetallic atoms can also effectively inhibit the hydrogen evolution reaction(HER)as well as improve the stability of the *** study proposes that the introduction of bimetallic atoms into C_(3)N is beneficial to break the linear relations and develop efficient NRR electrocatalysts.

关键词： nitrogen reduction reaction linear relations bimetallic atoms C_(3)N density functional theory

Enhancing carbon dioxide reduction electrocatalysis by tuning metal-support interactions: a first principles study

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Green Chemical Engineering 2023年第3期4卷 356-364页

作者： Riming Hu Yanan Yu Yongcheng Li Yiran Wang jiaxiang shang Xuchuan Jiang Institute for Smart Materials&Engineering University of JinanJinan250022China School of Physics and Electronics Shandong Normal UniversityJinan250358China Qinghai Provincial Key Laboratory of New Light Alloys Qinghai Provincial Engineering Research Center of High-Performance Light Metal Alloys and FormingQinghai UniversityXining810016China School of Materials Science and Engineering Beihang UniversityBeijing100191China School of Materials Science and Engineering University of JinanJinan250022China

The electrochemical reduction of CO_(2) is an extremely potential technique to achieve the goal of carbon neutrality,but the development of electrocatalysts with high activity,excellent product selectivity,and long-term durability remains a great ***,the role of metal-supports interaction(MSI)between different active sites(including single and bimetallic atom sites consisting of Cu and Ni atoms)and carbon-based supports(including C_(2) N,C_(3)N_(4),N-coordination graphene,and graphdiyne)on catalytic activity,prod-uct selectivity,and thermodynamic stability towards CO_(2) reduction reaction(CRR)is systematically investi-gated by first principles *** results show that MSI is mainly related to the charge transfer behavior from metal sites to supports,and different MSI leads to diverse magnetic moments and d-band ***,the adsorption and catalytic performance can be efficiently improved by tuning ***,the bimetallic atom supported graphdiyne not only exhibits a better catalytic activity,higher product selec-tivity,and higher thermodynamic stability,but also effectively inhibits the hydrogen evolution *** finding provides a new research idea and optimization strategy for the rational design of high-efficiency CRR catalysts.

关键词： Carbon dioxide reduction Metal-support interaction Bimetallic atoms Carbon-based support First-principles calculation

Critical role of carbon support in metal nanoaggregate facilitating Fe-N-C catalyst for PEM fuel cell application

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Journal of Energy Chemistry 2024年第10期97卷 669-676,I0014页

作者： Liming Guo Xin Wan Qingtao Liu Xiaofang Liu jiaxiang shang Ronghai Yu Jianglan Shui School of Materials Science and Engineering Beihang UniversityBeijing 100191China Tianmushan Laboratory Hangzhou 310023ZhejiangChina

Metal nanoaggregates can simultaneously enhance the activity and stability of Fe-N-C catalysts in proton-exchange-membrane fuel cells(PEMFC).Previous studies on the relevant mechanism have focused on the direct interaction between FeN_(4)active sites and metal ***,the role of carbon support that hosts metal nanoaggregates and active sites has been ***,a Fe-N-C catalyst encapsulating inactive gold nanoparticles is prepared as a model catalyst to investigate the electronic tuning of Au nanoparticles(NPs)towards the carbon *** NPs donate electrons to carbon support,making it rich inπelectrons,which reduces the work function and regulates the electronic configuration of the FeN_(4)sites for an enhanced ORR ***,the electron-rich carbon support can mitigate the electron depletion of FeN_(4)sites caused by carbon support oxidation,thereby preserving its high *** yield and accumulation of H_(2)O_(2)are thus alleviated,which delays the oxidation of the catalyst and benefits the *** to the electron-rich carbon support,the composite catalyst achieves a top-level peak power density of 0.74 W/cm^(2) in a 1.5 bar H_(2)-air PEMFC,as well as the improved *** work elucidates the key role of carbon support in the performance enhancement of the FeN-C/metal nanoaggregate composite catalysts for fuel cell application.

关键词： Fuel cells Oxygen reduction reaction Fe-N-C Hetero-structure catalyst Carbon support

Morphology evolution of SmCox permanent magnetic nanoparticles

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Science China(Physics,Mechanics & Astronomy) 2021年第4期64卷 104-110页

作者： Ying Dong Hui Wang BingJie Liu Xin Liu jiaxiang shang ZhiQi Liu TianLi Zhang ChengBao Jiang School of Materials Science and Engineering Beihang UniversityBeijing 100191China

Sm-Co nanoparticles (NPs) are promising candidates for preparing superstable magnets and exchange-coupled nanocomposite magnets with unprecedented magnetic ***,the morphology evolution of the NPs remains ***,single crystalline SmCox(x=4.07,4.79,6.94,and 8.61) NPs with dimensions below the critical size of a single magnetic domain were *** NPs consist of Sm_(2)Co_(7),SmCo_(5),and Sm2Co17phases with divergent typical *** evolution model for the different morphological characteristics was proposed based on phase-structure changes and surface-energy calculations using the density functional *** results show that these SmCo_(4.79) NPs can be well aligned along the easy magnetization axis and exhibit an ultrahigh coercivity of 5.7 T,thus enabling to advance the control of NP morphology and to facilitate their use in superstable or nanocomposite magnets.

关键词： Sm-Co permanent magnet nanoparticles morphology evolution ultrahigh coercivity

Precious trimetallic single-cluster catalysts for oxygen and hydrogen electrocatalytic reactions:Theoretical considerations

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Nano Research 2023年第5期16卷 8042-8050页

作者： Xiaochuan Shi Yongcheng Li Shan Zhang Riming Hu Shuang Gao Peipeng Jin jiaxiang shang Jianglan Shui Qinghai Provincial Key Laboratory of New Light Alloys Qinghai Provincial engineering Research Center of High Performance Light Metal Alloys and FormingQinghai UniversityXining 810016China Qinghai Communications Technical College Xining 810003China Institute for Smart Materials&Engineering University of JinanJinan 250022China School of Materials Science and Engineering Beihang UniversityBeijing 100191China

Single cluster catalysts(SCCs),which exhibit remarkable catalytic performance due to their high metal loading and synergy effect between metal atoms,have attracted great attention in ***,by means of density functional theory calculations,the oxygen reduction reaction(ORR),oxygen evolution reaction(OER),hydrogen evolution reaction(HER)performances of precious metal(Pt,Pd,Rh,Ir)trimetallic single-cluster electrocatalyst(U_(x)V_(y)W_(z)-NG)are *** calculation results show that Pt,Pd,Ir have significant effect on ORR,OER,HER,respectively,all the calculated U_(x)V_(y)W_(z)-NG structures are thermodynamically stable due to the negative formation energies and binding *** Pt_(3)-NG,Pd_(3)-NG,Ir_(3)-NG show the lowest ORR,OER,HER overpotentials of 0.63,0.77,−0.02 V,respectively,among all combinations of U_(x)V_(y)W_(z)-*** overpotentials are lower than that of precious metal single atom catalysts(SACs),which indicate better activities of precious trimetallic SCCs than those of *** electronic structure reveals that the O-2p orbital shows strong hybridization strength with Pt-3d orbitals in the system of OH adsorbed Pt_(3)-NG and thus facilitates the electrocatalytic *** results are helpful for the rational design of high-performance triatomic catalysts.

关键词： single-cluster catalysts trimetallic catalysts oxygen reduction reaction oxygen evolution reaction density functional theory

Catalysis stability enhancement of Fe/Co dual-atom site via phosphorus coordination for proton exchange membrane fuel cell

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Nano Research 2022年第4期15卷 3082-3089页

作者： Yinuo Wang Xin Wan Jieyuan Liu Wenwen Li Yongcheng Li Xu Guo Xiaofang Liu jiaxiang shang Jianglan Shui School of Materials Science and Engineering Beihang UniversityBeijing 100081China Qinghai Provincial Key Laboratory of New Light Alloys Qinghai Provincial Engineering Research Center of High-Performance Light Metal Alloys and FormingQinghai UniversityXining 810016China

Non-precious metal catalysts(NPMCs)are promising low-cost alternatives of Pt/C for oxygen reduction reaction(ORR),which however suffer from serious stability challenge in the devices of proton-exchange-membrane fuel cells(PEMFC).Different from the traditional strategies of increasing the degree of graphitization of carbon substrates and using less Fenton-reactive metals,we prove here that proper regulation of coordination anions is also an effective way to improve the stability of NPMC.N/P cocoordinated Fe-Co dual-atomic-sites are constructed on ZIF-8 derived carbon support using a molecular precursor of C_(34)H_(28)Cl_(2)CoFeP_(2)and a“precursor-preselected”method.A composition of FeCoN_(5)P1 is infered for the dual-atom active site by microscopy and spectroscopy *** comparing with N-coordinated references,we investigate the effect of P-coodination on the ORR catalysis of Fe-Co dual-atom catalysts in *** metals in FeCoN_(5)P1 have the lower formation energy than those in the solo N-coordinated active sites of FeCoN6 and FeN_(4),and exhibits a much better fuel cell *** anion approach provides a new way to improve the stability of dual-atom catalysts.

关键词： fuel cell oxygen reduction reaction non-precious metal catalyst dual atomic site P/N coordination

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过渡元素掺杂NiTi合金的第一性原理研究

稀有金属材料与工程 2016年第8期45卷 2041-2045页

作者：席蒙尚家香北京航空航天大学北京100191

采用基于密度泛函理论的第一性原理方法系统的计算了3d、4d和5d过渡元素掺杂的Ni Ti合金晶格参数、形成能、弹性常数和电荷密度,探讨了合金元素的占位倾向以及对马氏体相变温度的影响。计算结果表明,V、Cr、Mn、Fe、Co、Pd、Cu各族元素... 详细信息

采用基于密度泛函理论的第一性原理方法系统的计算了3d、4d和5d过渡元素掺杂的Ni Ti合金晶格参数、形成能、弹性常数和电荷密度,探讨了合金元素的占位倾向以及对马氏体相变温度的影响。计算结果表明,V、Cr、Mn、Fe、Co、Pd、Cu各族元素倾向于占据Ni位;Sc、Y、Zr、Hf倾向于占据Ti位。V、Cr、Mn、Fe、Co各族元素和Pd、Pt取代Ni,V、Cr、Mn、Fe各族取代Ti能够不同程度的降低NiTi合金的相变温度M_s;Hf、Zr、Au、Ag取代Ni以及Sc、Y、Hf、Zr取代Ti为能够升高NiTi合金的相变温度M_s;Cu取代Ni则基本不改变NiTi合金的相变温度M_s。这些结果与实验结果一致,进而从微观角度解释了合金元素对相变温度的影响规律。

关键词：过渡元素 NiTi合金第一性原理计算