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Stable Au nanoparticles confined in boron nitride shells for optimizing oxidative desulfurization

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Nano Research 2023年第10期16卷 12076-12083页

作者： Linjie Lu Jing He Peiwen Wu Yang Sun Mingqing Hua Peng Cui Wenshuai Zhu Huaming Li Zhichang Liu Chunming Xu School of Chemistry and Chemical Engineering Jiangsu UniversityZhenjiang 212013China College of Chemical Engineering and Environment State Key Laboratory of Heavy Oil ProcessingChina University of Petroleum(Beijing)Beijing 102249China

Supported gold(Au)nanocatalysts have long played an important role in numerous heterogeneous ***,the dominant difficulty of poor thermodynamic stability hampers its practical ***,a core–shell structured Au nanocatalyst with Au nanoparticles(NPs)confined in boron nitride(BN)shells is proposed for enhanced thermodynamic *** two-dimensional porous structure of BN not only functions as a physical separator for the sintering resistance of Au NPs,but also provides a microchannel for catalytic reaction ***,owing to the confinement effect,a strengthened interaction between well-designed Au NPs and the BN can be expected,which further boosts the stability and catalytic *** experiments show that a proper BN shell thickness is important to maintain the balance between the sintering resistance and catalytic activity.A significantly boosted performance of 97.2%conversion in oxidative desulfurization(ODS)was obtained with a proper number of BN coating layers,outperforming the one with a thicker BN ***,the recyclability of the prepared catalyst was investigated with no obvious decrease in catalytic performance after 10 runs,greatly higher than that without a BN shell,suggesting excellent durability.

关键词： oxidative desulfurization core–shell boron nitride Au nanocatalyst confinement effect

Hydrolysis Mechanism of Borazine-derived boron nitride Pyrolysized below 1200 ℃

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Journal of Materials Science & Technology 2012年第10期28卷 956-960页

作者： Feng Cao Kun Liu Zhenyu Fang Siqing Wang National Key Laboratory of Advanced Ceramic Fibers and Composites College of Aerospace and Materials EngineeringNational University of Defense TechnologyChangsha 410073China

boron nitride （BN） powders were synthesized by pyrolysis at various temperatures to investigate the hydrolysis mechanism of borazine-derived BN pyrolysized below 1200 ℃. The BN was hydrolysized near room tem-perature at 65% or 90% relative humidity （RH） over 45 days. The long-term hydrolysis mechanism and structure evolution were investigated by a measurement of mass growth and by X-ray diffraction （XRD）, Fourier-transform infrared （FT-IR） spectroscopy, and scanning electron microscopy （SEM） analyses. The sam-ples pyrolysized below 1200 ℃ were very sensitive to moisture, and their mass growth was closely related to the pyrolysis temperature. At 25 ℃ and 65% RH, the sample pyrolysized at 400 ℃ exhibited almost 100 wt% mass growth within 8 days, while the sample pyrolysized at 1200 ℃ exhibited about 20 wt% mass growth. The XRD analysis suggested a hydrolysis mechanism that corresponded to the interlayer spacing in the BN, which was consistent with the results reported. should be directly due to the residual N-H bonds On the other hand, the instability of borazine-derived BN in the compound, as suggested by FT-IR analysis.

关键词： Borazine Pyrolysis boron nitride Hydrolysis Stability

Improving hole transfer of boron nitride quantum dots modified PDI for efficient photodegradation

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Frontiers of Chemical Science and Engineering 2023年第11期17卷 1718-1727页

作者： Shiqing Ma Chundong Peng Zeyu Jia Yanmei Feng Kai Chen Hao Ding Daimei Chen Zhong-Yong Yuan Engineering Research Center of Ministry of Education for Geological Carbon Storage and Low Carbon Utilization of Resources Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid WastesNational Laboratory of Mineral MaterialsSchool of Material Sciences and TechnologyChina University of GeosciencesBeijing 100083China School of Materials Science and Engineering Nankai UniversityTianjin 300350China Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Jiangsu Key Laboratory of Atmospheric Environment Monitoringand Pollution Control School of Environmental Science and EngineeringNanjing University of Information Science and TechnologyNanjing 210044China

In recent years,organic photocatalyst under visible-light absorption has shown significant potential for solving environmental ***,it is still a great challenge for constructing a highly active organic photocatalyst due to the low separation efficiency of photogenerated ***,an effective and robust photocatalyst perylene-3,4,9,10-tetracarboxylic diamide/boron nitride quantum dots(PDI/BNQDs),consisting of selfassemble PDI withπ–πstacking structure and BNQDs,has been constructed and researched under visible light *** PDI/BNQDs composite gradually increases organic pollutant photodegradation with the loading amount of *** 10 mL of BNQDs solution added(PDI/BNQDs-10),the organic pollutant photodegradation performance reaches a maximum,about 6.16 times higher with methylene blue and 1.68 times higher with ciprofloxacin than that of pure PDI *** enhancement is attributed to improved separation of photogenerated carriers from self-assembled PDI by BNQDs due to their preeminent ability to extract *** work is significant for the supplement of PDI supramolecular composite *** believe that this photocatalytic design is capable of expanding organic semiconductors’potential for their applications in photocatalysis.

关键词： PDI boron nitride quantum dots photocatalysis hole transfer

Layered-structure N-doped expanded-graphite/boron nitride composites towards high performance of microwave absorption

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Journal of Materials Science & Technology 2022年第18期113卷 71-81页

作者： Zhuguang Nie Yang Feng Qing Zhu Ying Xia Liping Luo Lan Ma Jie Su Xingman Hu Rumin Wang Shuhua Qi School of Chemistry and Chemical Engineering Northwestern Polytechnical UniversityXi’an 710072China

High-efficiency microwave absorbers with broadband absorption are strongly desired for electromag-netic ***,we successfully synthesized a hybrid microwave absorbing material with two-dimensional layered structure,which consisted of expanded graphite(EG)and boron nitride(BN).The introduction of BN is to regulate the conductivity of EG and also to improve the thermal stability of the composite *** ultrathin BN nano-sheets were uniformly wrapped on the EG sheets via chemi-cal vapor *** to the dielectric loss and conductive loss,the as-prepared hybrid material exhibited high performance for microwave *** effective absorbing bandwidth(reflection loss value<-10 dB)was achieved up to 9.37 GHz with the thickness of 2.4 mm in the frequency range of 5.75-6.98 GHz and 9.86-18 *** the minimum reflection loss was-51.58 dB at the thickness of 3 *** excellent performance of microwave absorption was attributed to the dielectric loss,interfacial polarization loss and optimized impedance ***,compared to pure EG,the thermal de-composition temperature of EG/BN composite materials had increased by about 100℃which was up to 714℃.Taking the advantages of high thermal stability of BN as well as the fine microwave absorbability of EG,the EG/BN composites would be applied in high-temperature microwave absorbing fields.

关键词： Layered-structure Expanded graphite boron nitride Microwave absorption

The near-Surface Region of Cubic boron nitride Single Crystal from the Li3N-hBN System

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Chinese Physics Letters 2014年第4期31卷 182-184页

作者： GUO Xiao-Fei XU Bin WEN Zhen-Xing FAN Xiao-Hong TIAN Bin School of Materials Science and Engineering Shandong University Jinan 250061 School of Materials Science and Engineering Shandong Jianzhu University Jinan 250101

Cubic boron nitride single crystals are synthesized with lithium nitride as a catalyst under high pressure and high temperature. The main phases in the near-surface region, which around the single crystal are determined as a mixture of hexagonal boron nitride （hBN）, cubic boron nitride （cBN） and lithium boron nitride （Li3BN2）. High resolution transmission electron microscopy examinations show that there exist lots of nanometer-sized cubic boron nitride nuclei in this region. The interface phase structures of cubic boron nitride crystal and its near-surface region are investigated by means of transmission electron microscopy. The growth mechanism of cubic boron nitride crystal is analyzed briefly. It is supposed that LisBN2 impels the direct conversion of hBN to cBN as a real catalyst, and cBN is homogeneously nucleated in the molten state under high pressure and high temperature.

关键词： boron nitride SINGLE crystals -- Spectra LITHIUM nitrides HIGH resolution spectroscopy NUCLEATION TRANSMISSION electron microscopy

Two-dimensional boron nitride for Electronics and Energy Applications

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Energy & Environmental Materials 2022年第1期5卷 10-44页

作者： Jiemin Wang Liangzhu Zhang Lifeng Wang Weiwei Lei Zhong-Shuai Wu School of New Energy and Materials Southwest Petroleum UniversityChengdu Sichuan 610500China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Institute for Frontier Materials Deakin UniversityWaurn Ponds CampusLocked Bag 20000Geelong Vic.3220Australia Dalian National Laboratory for Clean Energy Chinese Academy of Sciences457 Zhongshan RoadDalian 116023China

Two-dimensional(2D)boron nitride(BN),the so-called“white graphene,”has demonstrated a great potential in various fields,particularly in electronics and energy,by utilizing its wide bandgap(~5.5 eV),superior thermal stability,high thermal conductance,chemical inertness,and outstanding dielectric ***,to further optimize the performances from the view of structure-property relationship,the determinative factors such as crystallite sizes,layer thickness,dispersibility,and surface functionalities should be precisely controlled and ***,in this review,the synthesis and functionalization methods including“top-down”and“bottom-up”strategies,and non-covalent and covalent modifications for 2D BN are systematically classified and discussed at first,thus catering for the requirements of versatile ***,the progresses of 2D BN applied in the fields of microelectronics such as fieldeffect transistors and dielectric capacitors,energy domains such as thermal energy management and conversion,and batteries and supercapacitors are summarized to highlight the importance of 2D ***,these contents not only contain the state-of-the-art 2D BN composites,but also bring the current novel design of 2D BN-based microelectronic ***,the challenges and perspectives are proposed to better broaden the scope of this ***,this review will pave an all-around way for understanding,utilizing,and applying 2D BN in future electronics and energy applications.

关键词： boron nitride electronics energy functionalization nanosheets two-dimensional materials

Seeing Dirac electrons and heavy fermions in new boron nitride monolayers

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Chinese Physics B 2020年第5期29卷 454-458页

作者： Yu-Jiao Kang Yuan-Ping Chen Jia-Ren Yuan Xiao-Hong Yan Yue-E Xie School of Physics and Optoelectronics Xiangtan UniversityXiangtan 411105China Faculty of Science Jiangsu UniversityZhenjiang 212013China

Most three-dimensional(3D)and two-dimensional(2D)boron nitride(BN)structures are wide-band-gap ***,we propose two BN monolayers having Dirac points and flat bands,*** monolayer is named as 5-7 BN that consists of five-and seven-membered *** other is a Kagome BN made of triangular boron rings and nitrogen *** two structures show not only good dynamic and thermodynamic stabilities but also novel electronic *** 5-7 BN has Dirac points on the Fermi level,indicating that the structure is a typical Dirac *** Kagome BN has double flat bands just below the Fermi level,and thus there are heavy fermions in the *** flat-band-induced ferromagnetism is also *** analyze the origination of the band structures by partial density of states and projection of *** addition,a possible route to experimentally grow the two structures on some suitable substrates such as the PbO2(111)surface and the CdO(111)surface is also discussed,*** research not only extends understanding on the electronic properties of BN structures,but also may expand the applications of BN materials in 2D electronic devices.

关键词： boron nitride Dirac fermion flat band ferromagnetism

Strain Effects on Electronic Properties of boron nitride Nanoribbons

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Chinese Physics Letters 2010年第7期27卷 214-217页

作者：李金孙立忠钟建新 Laboratory for Quantum Engineering and Micro-Nano Energy Technology Xiangtan University Xiangtan 411105 Department of Physics Xiangtan University Xiangtan 411105

We investigate the strain effects on the electronic properties of boron nitride nanoribbons （BNNFts） by using firstprinciples calculations. The results show that the energy gap of BNNRs with both armchair edges （A-BNNRs） and zigzag edges （Z-BNNFts） decreases as the strain increases. As strain increases, the energy gaps of Z-BNNRs decrease rapidly as the width increases and reduce significantly to small values, which makes Z-BNNRs change from wide-gap to narrow-gap semiconductors.

关键词： boron nitride NANOSTRUCTURED materials MATERIALS -- Electric properties ENERGY gaps (Physics) STRAINS & stresses (Mechanics) SEMICONDUCTORS

Multi-step Reaction Route Developed for Improving Crystallinity of boron nitride Nanoparticles

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Chemical Research in Chinese Universities 2012年第3期28卷 387-390页

作者： TAN Miao LIAN Gang ZHANG Xiao ZHANG Shun-jie CUI De-liang WANG Qi-long State Key Laboratory of Crystal Materialst Shandong UniversityJinan 250100P.R.China School of Chemistry&Chemical Engineering Shandong UniversityJinan 250100P.R.China

A multi-step reaction route was developed to synthesize boron nitride（BN） nanoparticles via the reactionbetween NaN3 and BC13 in a benzene-thermal solution. By means of this route, the crystallinity of BN nanoparticleswas improved via increasing the reaction steps. Meanwhile, a phase transformation from hexagonal BN（hBN） or tur-bostratic BN（tBN） to cubic BN（cBN） occurred, resulting in the increase of cBN content. Moreover, the content ofcBN also slightly increased when the temperature was elevated from 265 ℃ to 280 ℃.

关键词： boron nitride Multi-step reaction route Benzene-thermal synthesis Phase transformation