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framework structure engineering of polymeric carbon nitrides and its recent applications

PROGRESS IN MATERIALS SCIENCE 2023年第1期133卷

作者： Tian, Bin Ho, Derek Qin, Jiaqian Hu, Jinguang Chen, Zhangxing Voiry, Damien Wang, Qian Zeng, Zhiyuan City Univ Hong Kong Dept Mat Sci & Engn 83 Tat Chee Ave Hong Kong Peoples R China City Univ Hong Kong State Key Lab Marine Pollut 83 Tat Chee Ave Hong Kong Peoples R China City Univ Hong Kong Shenzhen Res Inst Shenzhen 518057 Peoples R China Chulalongkorn Univ Met & Mat Sci Res Inst Ctr Excellence Respons Wearable Mat Bangkok 10330 Thailand Univ Calgary Dept Chem & Petr Engn 2500 Univ Dr NW Calgary AB T2N 1N4 Canada Univ Montpellier Inst Europeen Membranes IEM UMR 5635ENSCMCNRS Montpellier France Nagoya Univ Grad Sch Engn Furo ChoChikusa Ku Nagoya 4648603 Japan Nagoya Univ Inst Adv Res Furo ChoChikusa Ku Nagoya 4648601 Japan Chinese Acad Sci Suzhou Inst Nanotech & Nanobion Div Adv Nanomat Suzhou Peoples R China

Polymeric carbon nitrides (CN) as star semiconductive materials have attracted increasing attention owing to its numerous superior features, such as facile synthesis, non-toxicity, earthabundant, high physicochemical stability, and all of these endow its great potentials from photocatalysis to environmental remediation, sensing, biomedicine, and other emerging fields. The facile synthesis and polymeric characteristic of CN allow easy tailoring of their framework from elements, the structure of monomers, and tectonic units to control their properties and then to obtain superior performance in various applications. Although there have been reviews summarizing design and modification strategies of CN-based materials, most of them have focused only on surface engineering and nanostructure construction, lacking analysis from the point of view of the framework structure. This review systematically summarized the inspiring breakthroughs on rational design and fabrication of the CN framework from elements to monomers, and then to tectonic units via various strategies including elemental doping, defects engineering, tuning the crystalline degree, coordination engineering and molecular doping. Importantly, we summarized general rules between CN framework structure and their performance in various applications to better understand the current state-of-the-art status and plans for future research directions.

关键词： Polymeric carbon nitrides framework structure structure engineering Various applications

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Ni3Te2O2(PO4)2(OH)4, an open-framework structure isotypic with Co3Te2O2(PO4)2(OH)4

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ACTA CRYSTALLOGRAPHICA SECTION E-CRYSTALLOGRAPHIC COMMUNICATIONS 2020年第5期76卷 625-+页

作者： Eder, Felix Weil, Matthias TU Wien Inst Chem Technol & Analyt Div Struct Chem Getreidemarkt 9-164-SC A-1060 Vienna Austria

Single crystals of Ni-3(TeO(OH)(2))(2)(PO4)(2), trinickel(II) bis[(oxidodihydoxidotellurate(IV)] bis(phosphate),were obtained by hydrothermal synthesis at 483 K, starting from NiCO3 center dot 2Ni(OH)(2), TeO2 and H3PO4 in a molar ratio of 1:2:2. The crystal structure of Ni3Te2O2(PO4)(2)(OH)(4) is isotypic with that of Co3Te2O2(PO4)(2)(OH)(4) [Zimmermann et al. (2011). J. Solid State Chem. 184, 3080-3084]. The asymmetric unit comprises two Ni (site symmetries 1, 2/m) one Te (m), one P (m), five O (three m, two 1) and one H (1) sites. The tellurium(IV) atom shows a coordination number of five, with the corresponding [TeO3(OH)(2)] polyhedron having a distorted square-pyramidal shape. The two NiII atoms are both octahedrally coordinated but form different structural elements: one constitutes chains made up from edge-sharing [NiO6] octahedra extending parallel to [010], and the other isolated [NiO2(OH)(4)] octahedra. The two kinds of nickel/oxygen octahedra are connected by the [TeO3(OH)(2)] pyramids and the [PO4] tetrahedra through edge- and corner-sharing into a three-dimensional framework structure with channels extending parallel to [010]. Hydrogen bonds of medium strength between the hydroxy groups and one of the phosphate O atoms consolidate the packing. A quantitative structure comparison between Ni3Te2O2(PO4)(2)(OH)(4) and Co3Te2O2(PO4)(2)(OH)(4) is made.

关键词： crystal structure oxidotellurate(IV) phosphate framework structure isotypism structure comparison

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Negative thermal expansion in framework structure materials

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COORDINATION CHEMISTRY REVIEWS 2021年 449卷 214204-214204页

作者： Shi, Naike Song, Yuzhu Xing, Xianran Chen, Jun Univ Sci & Technol Beijing Beijing Adv Innovat Ctr Mat Genome Engn Beijing 100083 Peoples R China Univ Sci & Technol Beijing Dept Phys Chem Beijing 100083 Peoples R China Univ Sci & Technol Beijing Inst Solid State Chem Beijing Adv Innovat Ctr Mat Genome Engn Beijing 100083 Peoples R China Univ Sci & Technol Beijing Sch Math & Phys Beijing 100083 Peoples R China

Negative thermal expansion (NTE) is a counterintuitive physical phenomenon that the unit cell volume of material usually contracts instead of expands upon heating. With two decades' development, NTE has been discovered in many kinds of compounds, in which framework structure materials account for the major part. The flexible bridging linkage units and relatively large void in the crystal structure of framework structure materials facilitate the transverse vibration of atoms, resulting the intriguing NTE. A growing number of framework structure NTE materials have been discovered from the earliest studied oxides, cyanides, metal-organic frameworks (MOFs), and then to fluorides. In this paper, framework NTE materials are reviewed thoroughly in terms of chemical formulas and crystal structures, which involve oxides, fluorides, cyanides, and MOFs. The thermal expansion property of framework structure materials is closely associated with the structure character that a larger framework with more flexible bridge groups encourages a stronger NTE. Since the metal atom size impacts the volume of framework structure, the magnitude of NTE is also sensitive to the metal atom size in a specific crystal structure classification. Accordingly, control methods of thermal expansion aiming at framework structures are summarized, including chemical substitution, local structure distortion, and guest molecular or ions intercalation. As for the control of thermal expansion, chemical substitution is the most widespread method. The recently proposed method of guest molecular or ions intercalation is most effective for the thermal expansion control in large framework structures such as cyanides and MOFs. The local structure distortion shows a significant effect in fluorides, which can be extended to other systems. At last, problems and future developments of framework structure NTE materials are discussed from the aspects of discovery and design of new NTE materials, NTE mechanism, thermal ex

关键词： Negative thermal expansion framework structure Transverse vibration

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M³⁺(H₂AsO₄)( H₂As₂O₇) (M³⁺ = Al, Ga) and In₂( H₂AsO₄)₂(H₂As₂O₇)₂: a new layer structure type and a new framework structure type containing the rare H₂As₂O₇^2- group

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ACTA CRYSTALLOGRAPHICA SECTION C-STRUCTURAL CHEMISTRY 2017年第8期73卷 600-+页

作者： Schwendtner, Karolina Kolitsch, Uwe TU Wien Div Struct Chem Inst Chem Technol & Analyt Getreidemarkt 9 A-1060 Vienna Austria Nat Hist Museum Wien Mineral Petrog Abt Burgring 7 A-1010 Vienna Austria Univ Vienna Inst Mineral & Kristallog Althanstr 14 A-1090 Vienna Austria

The crystal structures of hydrothermally synthesized aluminium dihydrogen arsenate(V) dihydrogen diarsenate(V), Al(H2AsO4)(H2As2O7), gallium dihydrogen arsenate(V) dihydrogen diarsenate(V), Ga(H2AsO4)(H2As2O7), and diindium bis[dihydrogen arsenate(V)] bis[dihydrogen diarsenate(V)], In-2(H2AsO4) (2)(H2As2O7)(2), were determined from single-crystal X-ray diffraction data collected at room temperature. The first two compounds are representatives of a novel sheet structure type, whereas the third compound crystallizes in a novel framework structure. In all three structures, the basic building units are M3+O6 octahedra (M = Al, Ga, In) that are connected via one H2AsO4-and two H(2)As(2)O(7)(2-)groups into chains, and further via H2As2O72- groups into layers. In Al/Ga(H2AsO4)(H2As2O7), these layers are interconnected by weak-tomedium-strong hydrogen bonds. In In-2(H2AsO4)(2)(H2As2O7)(2), the H2As2O72-groups link the chains in three dimensions, thus creating a framework topology, which is reinforced by weak-to-medium-strong hydrogen bonds. The three title arsenates represent the first compounds containing both H2AsO4 and H2As2O72-groups.

关键词： dihydrogen arsenate(V) dihydrogen diarsenate(V) aluminium gallium indium sheet structure crystal structure framework structure

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Comparative Study of Methanol to Olefins Over ZSM-5, ZSM-11, ZSM-22 and EU-1: Dependence of Catalytic Performance on the Zeolite framework structure

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JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2017年第6期17卷 3680-3688页

作者： Jing, Buqin Li, Junfen Li, Zhikai Wang, Sen Qin, Zhangfeng Fan, Weibin Wang, Jianguo Chinese Acad Sci Inst Coal Chem State Key Lab Coal Convers POB 165 Taiyuan 030001 Shanxi Peoples R China Shanxi Datong Univ Coll Chem & Environm Engn Datong 037009 Shanxi Peoples R China Univ Chinese Acad Sci Beijing 100049 Peoples R China

The conversion of methanol to olefins (MTO) was comparatively conducted over four 10-ring zeolites, viz., ZSM-5, ZSM-11, ZSM-22 and EU-1, in both continuous-flow and pulse reactors, to reveal the relation between the catalytic performance and framework structure. The results illustrate that the performance of a zeolite catalyst in MTO is closely dependent on its framework structure. Among four zeolites, ZSM-5 with three dimensional channels and intersections exhibits the highest catalytic activity and stability in MTO. In comparison with ZSM-5 and ZSM-11, ZSM-22 and EU-1 are deactivated much more rapidly due to the blockage of the pore opening. Especially, the straight channels of ZSM-11 facilitate the orderly array of butene molecules in the channels, which may promote the hydrogen transfer reaction and lead to high selectivity to butane and C5+ products, in comparison with ZSM-5. The hydrocarbon pool mechanism is also applicable in ZSM-22, though less important;the 1D straight channels in ZSM-22 are easily blocked, leading to the quick deactivation. EU-1 zeolite exhibits quite high selectivity to propene due to its large 12-ring side-pockets in which polyalkylbenzenes are formed as the hydrocarbon pool species. The insights shown in this work are conducive to the development of better MTO catalysts and reaction processes.

关键词： Methanol to Olefins ZSM-5 ZSM-22 ZSM-11 EU-1 framework structure Pulse Reaction

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framework structure on Personnel Training Mode for Tourism Management Major of Middle Vocational Undergraduate

Framework Structure on Personnel Training Mode for Tourism M...

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2015 3rd International Conference on Education,Management,Arts,Economics and Social Science(ICEMAESS 2015)

作者： Hongyan Liu College of Finance and Trade Bohai University

Vigorous development of the tourism industry provides new opportunities for the construction of Tourism Management Specialty in Colleges and universities. This paper is aimed at the problems in the cultivation of the middle vocational undergraduate tourism management major personnel training mode, to improve the quality of personnel training services. With the characteristics of the students in secondary vocational college, based on the goal of personnel cultivation and social needs, the seven framework structure is built, which is a positioning, two systems, three training, four module, five flat, six kinds of knowledge and nine skills. The successful application of the research results of this paper is of great significance in improving students’ quality, innovative training methods, strengthening students’ ability and adapting to social development.

关键词： middle vocational undergraduate tourism management major personnel training mode framework structure

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Research on framework structure for Examination Achievement Management System

Research on Framework Structure for Examination Achievement ...

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2015 2nd International Conference on Civil,Materials and Environmental Sciences(CMES 2015)

作者： Jun Yang School of Education and Sports Bohai University

Examination achievement management system is an important part of college educational administration system and plays an important role to improve the level of educational management. In view of the problem of the difficulty of software development, this article launches the research on the framework structure. First of all, this article researches basic framework structure based on Struts2, illustrates the process that Struts2 handles requests;then, this article researches 4 layer framework structure of the software and illustrates the effect of the client layer, presentation layer, business logic layer and data access layer effect;Finally, this article researches data access framework structure based on Spring JDBC, and describes the four kinds of data operation. The research results of this article can develop the examination achievement management system which adopts clear structure, easy to maintain, can also provide reference for the development of other systems.

关键词： examination achievement management system framework structure basic framework software framework data access framework

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framework structure Design on College English Assisted Instruction System

Framework Structure Design on College English Assisted Instr...

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International Conference on Mechatronics and Semiconductor Materials (ICMSCM 2013)

作者： Rui, Li Bohai Univ Coll Foreign Languages Jinzhou Peoples R China

ISBN: (纸本)9783037859391

Faculty shortage of college English teaching which is caused by the reform, limit the improvements of students' English proficiency, and an effective mechanism to resolve this contradiction is the English assisted instruction system. This paper makes research on the frame structure, aiming at the problems in the process of system development and maintenance. First, study the functional framework composed by three roles, students, teachers, administrators, based on the analysis of system function;Then, research framework, on the presentation layer, business logic layer, data access layer, so it is easy for developers to complete the business process specific in the framework;Finally, research on security framework composed by ***, ITS,.NET framework, the operating system. College English assisted instruction system, based on the construction of the framework structure, can achieve the ability of sharing teaching resources, enriching teaching mode, and improving the quality of teaching.

关键词： college English assisted instruction system framework structure functional framework technical framework security framework

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Heterogeneous interface engineering of CoPSe and FePSe3 on open frameworks for boosting highly efficient overall water splitting

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CHEMICAL ENGINEERING JOURNAL 2024年 496卷

作者： Gu, Peng Song, Yidong Fan, Yihe Liu, Jin Meng, Xin Xie, Jiahao Li, Yuxin Li, Zhouguanwei Sun, Heyuan Nie, Yao Zou, Jinlong Heilongjiang Univ Heilongjiang Prov Key Lab Environm Nanotechnol Harbin 150080 Peoples R China Heilongjiang Univ Sch Chem & Mat Sci Key Lab Funct Inorgan Mat Chem Minist Educ Peoples Republ China Harbin Peoples R China

Enhancing intrinsic activity of nanostructured heterogeneous catalysts is an effective strategy for improving electrocatalytic performance for hydrogen/oxygen evolution reactions (HER/OER), but it remains challenging. Here, phosphorus (P) and selenium (Se) atoms are incorporated into an open Co-Fe-based Prussian blue analogues to form a heterostructure consisting of CoPSe and FePSe3 via a one-step pyrolysis strategy. The CoPSe/ FePSe3 heterojunction greatly reduces the overpotential for HER (91 mV) or OER (172 mV), which is close to that of Pt/C or much better than that of RuO2, respectively. Co-doping of P and Se non-metallic atoms promotes the reaction kinetics and the exposure of active sites in the framework structure with a large specific surface area. The interactions between CoPSe and FePSe3 can eagerly promote the interfacial electron transfer to enhance HER/OER activities. The carbon skeleton can effectively avoid the fast corrosion/aggregation of the embedded CoPSe/FePSe3 heterojunctions, thereby enhancing the catalytic/structural stability for HER/OER. Importantly, for overall water splitting, the electrolyzer with CoPSe/FePSe3 catalyst only requires an overpotential of 0.35 V to achieve a long-term stability (36 h) at 10 mA cm(- 2), with Faradaic efficiencies near 100 %. This work sheds a new light on promotion of intrinsic activity of heterostructured catalysts for water splitting.

关键词： framework structure Heterostructure Interface One-step phosphoselenization Water splitting

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Preparation of the Coating on the C/C-SiC Composite from the Mo-HfSi2-SiB4 Composition by the In Situ Reaction Synthesis

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RUSSIAN METALLURGY 2024年第3期2024卷 681-689页

作者： Astapov, A. N. Belokopytova, E. S. Matulyak, A. I. Pogodin, V. A. Soldatenko, I. V. Natl Res Univ Moscow Aviat Inst Moscow 125993 Russia

The coating based on the MoSi2-MoB-HfB2 system on the substrate of the C/C-SiC composite is prepared by the in situ reaction synthesis using the slurry-roasting deposition of the powder composition at 1620 degrees C under an argon expansion pressure of similar to 1 Pa. The reaction mechanisms in the Mo-HfSi2-SiB4-C system predetermining the synthesis of secondary phases MoSi2, MoB, HfB2, and HfC are proposed. Thermodynamic calculations of possible chemical reactions are performed. Probable causes for a high porosity of the prepared coating are analyzed.

关键词： carbon-carbon composite materials (CCCM) carbon-ceramic composite materials (CCeCM) protective coating slurry reaction synthesis in situ sintering framework structure porosity

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