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Application of topology-based structure features for machine learning in materials science

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Chinese Journal of Structural Chemistry 2023年第7期42卷 47-53页

作者： shisheng zheng Haowen Ding Shunning Li Dong Chen Feng Pan School of Advanced Materials Peking University Shenzhen Graduate SchoolShenzhenGuangdong518055PR China Department of Mathematics Michigan State UniversityEast Lansing MIUSA

Structure features play an important role in machine learning models for the materials ***,two topology-based features for the representation of material structure,specifically structure graph and algebraic topology,are *** present the fundamental mathematical concepts underlying these techniques and how they encode material ***,we discuss the practical applications and enhancements of these features made in specific material predicting *** review may provide suggestions on the selection of suitable structural features and inspire creativity in developing robust descriptors for diverse applications.

关键词： Machine learning Structure feature Structure graph Algebraic topology

Mo doped Ru-based cluster to promote alkaline hydrogen evolution with ultra-low Ru loading

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Chinese Journal of Structural Chemistry 2023年第11期42卷 6-12页

作者： Haibin Yang Duowen Ma Yang Li Qinghe Zhao Feng Pan shisheng zheng Zirui Lou School of Advanced Materials Peking University Shenzhen Graduate SchoolShenzhenGuangdong518055PR China Hydrogen Energy Institute Zhejiang UniversityHangzhou310000PR China

Green hydrogen energy developed through electrochemistry is one of the solutions to current energy *** less noble metal ruthenium(Ru)plays an important role in alkaline electrocatalytic hydrogen evolution reaction(HER)as an effective ***,the high cost(>110 RMB per gram)hinders the large-scale application of Ru in industrial hydrogen ***,the strong adsorption of OH*in-termediates over Ru limits the electrocatalytic performance in alkaline ***,we report the Mo-doped Ru nanocluster embedded on N-doped carbon framework(RuMo/NC)as alkaline HER catalyst,which shows excellent catalytic performance with an overpotential of 24.2 mV to reach 10 mA cm-2 with only 0.4 wt%o of Ru,much lower than that of most reported Ru-based *** calculations reveal the introduction of Mo has improved the activity by alleviating the poisoning effect of OH*over Ru in *** fully utilizing Ru in the catalyst,this work marks a step forward in the development of Ru-based catalysts in alkaline HER.

关键词： Hydrogen evolution reaction Ru-based electrocatalyst OH*poison DFT calculation

Constructing low-valent Ni nanoparticles for highly selective CO_(2) reduction

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Chinese Chemical Letters 2022年第1期33卷 424-427页

作者： Kuanda Xu shisheng zheng Yang Li Honghao Chu Qi Xiong Zongwei Mei Qinghe Zhao Luyi Yang Shunning Li Feng Pan School of Advanced Materials Peking University Shenzhen Graduate SchoolShenzhen 518055China

The electroreduction of CO_(2)(CO_(2)RR)into value-added chemicals is a sustainable strategy for mitigating global warming and managing the global carbon ***,developing an efficient and selective catalyst is still the central ***,we developed a simple two-step pyrolysis method to confine low-valent Ni-based nanoparticles within nitrogen-doped carbon(Ni-NC).As a result,such Ni-based nanoparticles can effectively reduce CO_(2)to CO,with a maximum CO Faradaic efficiency(FE)of 98%at an overpotential of 0.8 V,as long as good *** and the density functional theory(DFT)calculation results reveal that low-valent Ni plays a key role in activity and selectivity *** study presents a new understanding of Ni-based CO_(2)RR,and provides a simple,scalable approach to the synthesis of low-valent catalysts towards efficient CO_(2)RR.

关键词： CO_(2)reduction reaction Ni-based catalysts Electrocatalytic selectivity Low-valent catalyst DFT calculation

Li-rich channels as the material gene for facile lithium diffusion in halide solid electrolytes

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eScience 2022年第1期2卷 79-86页

作者： Guohao Yang Xianhui Liang shisheng zheng Haibiao Chen Wentao Zhang Shunning Li Feng Pan School of Advanced Materials Peking UniversityShenzhen Graduate SchoolShenzhen518055People's Republic of China Institute of Marine Biomedicine Shenzhen PolytechnicShenzhen518055People's Republic of China

Halide solid electrolytes have attracted intense research interest recently for application in all-solid-state lithiumion batteries. Herein, we present a systematic first-principles study of the Li3MX6 (M: multivalent cation;X:halogen anion) halide family that unveils the link between Li-rich channels and ionic conductivity, highlightingthe former as a material gene in these compounds. By screening a total of 180 halides for those with highthermodynamic stability, wide electrochemical window, low chemical reactivity, and decent Li-ion conductivity,we identify seven unexplored candidates for solid electrolytes. From these halides and another four prototypecompounds, we discover that the facile Li diffusion is rooted in the availability of diffusion pathways which canavoid direct connection with M cations-that is, where the local environment is Li-rich. These findings shed lighton strategies for regulating cation and anion frameworks to establish Li-rich channels in the design of high-performance inorganic solid electrolytes.

关键词： Li-ion batteries Inorganic solid electrolytes Halides Material gene Density functional theory

Valence state of transition metal center as an activity descriptor for CO_(2) reduction on single atom catalysts

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Journal of Energy Chemistry 2021年第5期30卷 444-448页

作者： shisheng zheng Changjian Zuo Xianhui Liang Shunning Li Feng Pan School of Advanced Materials Peking UniversityShenzhen Graduate SchoolShenzhen 518055GuangdongChina

Carbon dioxide(CO_(2))catalytic reduction has been passionately pursued for a long period of time due to its special importance in alleviating the greenhouse effect as well as generating valuable fuels and chemicals[1].Among the various approaches for achieving CO_(2)conversion,considerable efforts have been devoted to electrochemical reduction of CO_(2)since this technology operates at ambient and mild environments and can potentially produce various useful products[2].

关键词： CO_(2)conversion MXene based single-atom catalysts Activity descriptor Volcano shape relationship First principles calculation

Identify crystal structures by a new paradigm based on graph theory for building materials big data

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Science China Chemistry 2019年第8期62卷 982-986页

作者： Mouyi Weng Zhi Wang Guoyu Qian Yaokun Ye Zhefeng Chen Xin Chen shisheng zheng Feng Pan School of Advanced Materials Peking UniversityShenzhen Graduate School

Material identification technique is crucial to the development of structure chemistry and materials genome project. Current methods are promising candidates to identify structures effectively, but have limited ability to deal with all structures accurately and automatically in the big materials database because different material resources and various measurement errors lead to variation of bond length and bond angle. To address this issue, we propose a new paradigm based on graph theory(GTscheme) to improve the efficiency and accuracy of material identification, which focuses on processing the "topological relationship" rather than the value of bond length and bond angle among different structures. By using this method, automatic deduplication for big materials database is achieved for the first time, which identifies 626,772 unique structures from 865,458 original ***, the graph theory scheme has been modified to solve some advanced problems such as identifying highly distorted structures, distinguishing structures with strong similarity and classifying complex crystal structures in materials big data.

关键词： structures identification graph theory big data topological relationship materials database

Wavelength-Dependent Solar N_(2) Fixation into Ammonia and Nitrate in Pure Water

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Research 2020年第1期2020卷 581-592页

作者： Wenju Ren Zongwei Mei shisheng zheng Shunning Li Yuanmin Zhu Jiaxin zheng Yuan Lin Haibiao Chen Meng Gu Feng Pan School of Advanced Materials Peking UniversityShenzhen Graduate SchoolChina School of Advance Manufacturing Engineering Chongqing University of Posts and TelecommunicationsChongqingChina Department of Materials Science and Engineering Southern University of Science and TechnologyChina SUSTech Academy for Advanced Interdisciplinary Studies Southern University of Science and TechnologyChina Institute of Chemistry Chinese Academy of SciencesBeijingChina

Solar-driven N_(2) fixation using a photocatalyst in water presents a promising alternative to the traditional Haber-Bosch process in terms of both energy efficiency and environmental *** present,the product of solar N_(2) fixation is either NH_(4)^(+)or NO_(3)^(-).Few reports described the simultaneous formation of ammonia(NH_(4)^(+))and nitrate(NO_(3)^(-))by a photocatalytic reaction and the related *** this work,we report a strategy to photocatalytically fix nitrogen through simultaneous reduction and oxidation to produce NH_(4)^(+)and NO_(3)^(-)byW18O49 nanowires in pure *** underlying mechanism of wavelength-dependent N_(2) fixation in the presence of surface defects is proposed,with an emphasis on oxygen vacancies that not only facilitate the activation and dissociation of N_(2) but also improve light absorption and the separation of the photoexcited *** NH_(4)^(+)and NO_(3)^(-)can be produced in pure water under a simulated solar light and even till the wavelength reaching 730 *** maximum quantum efficiency reaches 9%at 365 *** calculation reveals that disproportionation reaction of the N_(2) molecule is more energetically favorable than either reduction or oxidation *** is worth noting that the molar fraction of NH_(4)^(+)in the total product(NH_(4)^(+)plus NO_(3)^(-))shows an inverted volcano shape from 365nm to 730 *** increased fraction of NO_(3)^(-)from 365 nm to around 427 nm results from the competition between the oxygen evolution reaction(OER)at W sites without oxygen vacancies and the N_(2) oxidation reaction(NOR)at oxygen vacancy sites,which is driven by the intrinsically delocalized photoexcited *** 427nm to 730 nm,NOR is energetically restricted due to its higher equilibrium potential than that of OER,accompanied by the localized photoexcited holes on oxygen *** disproportionation of N_(2) is achieved within a range of wavelength from~427nm to~515 *** work presents a rati

关键词： mechanism excited catalyst

A descriptor of “material genes”: Effective atomic size in structural unit of ionic crystals

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Science China(Technological Sciences) 2019年第5期62卷 849-855页

作者： CHEN Dong LI ShunNing JIE JianShu LI SiBai zheng shisheng WENG MouYi YU ChangCheng LI ShuCheng CHEN DaJun PAN Feng School of Advanced Materials Shenzhen Graduate School Peking University

The atomic size of each element, described by the ionic radius, is one category of "material genes" and can facilitate our understanding of atomic arrangements in compounds. Most of the ionic radii currently used to measure the sizes of cations and anions in ionic crystals are derived from hard-sphere model based on the coordination numbers, or the soft-sphere model incorporating the effect of ionic polarization. Herein we take a first step towards a novel "effective atomic size"(EAS) model,which takes into consideration the impact of the types and number of neighboring atoms on the relationship between ionic radii and interatomic distances. Taking the binary compounds between Group IA/IIA and VIA/VIIA elements gathered from the latest databases as an example, we show that the proposed EAS model can yield excellent agreement between the predicted and the DFT-calculated interatomic distances, with deviation of less than 0.1 ?. A set of EAS radii for ionic crystals has been compiled and the role of coordination numbers, geometric symmetry and distortion of structural units has been examined. Thanks to its superior predictability, the EAS model can serve as a foundation to analyze the structure of newly-discovered compounds and to accelerate materials screening processes in the future works.

关键词： ionic radii interatomic distance effective atomic size coordination environment structural units

Modulating proton binding energy on the tungsten carbide nanowires surfaces for boosting hydrogen evolution in acid

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Journal of Energy Chemistry 2021年第11期30卷 610-616,I0014页

作者： Qjngshui Hong Tangyi Li shisheng zheng Haibiao Chen Wenju Ren Honghao Chu Kuangda Xu Zongwei Mei Feng Pan School of Advanced Materials Peking UniversityShenzhen Graduate SchoolShenzhen 518055GuangdongChina School of Advance Manufacturing Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China

ungsten carbides have attracted wide attentions as Pt substitute electrocatalysts for hydrogen evolution reaction (HER), due to their good stability in an acid environment and Pt-like behaviour in hydrolysis. However, quantum chemistry calculations predict that the strong tungsten-hydrogen bonding hinders hydrogen desorption and restricts the overall catalytic activity. Synergistic modulation of host and guest electronic interaction can change the local work function of a compound, and therefore, improve its electrocatalytic activity over either of the elements individually. Herein, we develop a creative and facile solid-state approach to synthesize self-supported carbon-encapsulated single-phase WC hybrid nanowires arrays (nanoarrays) as HER catalyst. The theoretical calculations reveal that carbon encapsulation modifies the Gibbs free energy of H* values for the WC adsorption sites, endowing a more favorable C@WC active site for HER. The experimental results exhibit that the hybrid WC nanoarrays possess remarkable Pt-like catalytic behavior, with superior activity and stability in an acidic media, which can be compared to the best non-noble metal catalysts reported to date for hydrogen evolution reaction. The present results and the facile synthesis method open up an exciting avenue for developing cost-effective catalysts with controllable morphology and functionality for scalable hydrogen generation and other carbide nanomaterials applicable to a range of electrocatalytic reactions.

关键词： Carbon-encapsulated tungsten carbide Solid-state synthesis Self-supported nanoarrays electrode Hydrogen evolution reaction First-principles calculations