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An Efficient Boron Source Activation Strategy for the Low‑Temperature Synthesis of Boron Nitride Nanotubes
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作者 Ying Wang Kai Zhang +10 位作者 Liping Ding Liyun Wu Songfeng E Qian He Nanyang Wang Hui Zuo Zhengyang Zhou Feng Ding Yue Hu Jin Zhang Yagang Yao 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期548-558,共11页
Lowering the synthesis temperature of boron nitride nanotubes(BNNTs)is crucial for their development.The primary reason for adopting a high temperature is to enable the effective activation of highmelting-point solid ... Lowering the synthesis temperature of boron nitride nanotubes(BNNTs)is crucial for their development.The primary reason for adopting a high temperature is to enable the effective activation of highmelting-point solid boron.In this study,we developed a novel approach for efficiently activating boron by introducing alkali metal compounds into the conventional MgO–B system.This approach can be adopted to form various low-melting-point AM–Mg–B–O growth systems.These growth systems have improved catalytic capability and reactivity even under low-temperature conditions,facilitating the synthesis of BNNTs at temperatures as low as 850℃.In addition,molecular dynamics simulations based on density functional theory theoretically demonstrate that the systems maintain a liquid state at low temperatures and interact with N atoms to form BN chains.These findings offer novel insights into the design of boron activation and are expected to facilitate research on the low-temperature synthesis of BNNTs. 展开更多
关键词 Boron nitride nanotubes LOW-TEMPERATURE Boron activation Density functional theory
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hBN含量对hBN/聚氨酯丙烯酸酯复合材料力学和摩擦学性能的影响
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作者 胡海霞 刘正果 《机械工程材料》 CAS CSCD 北大核心 2024年第9期74-80,共7页
采用硅烷偶联剂KH550对六方氮化硼(hBN)纳米颗粒进行表面改性处理,利用立体光刻技术制备不同质量分数(0.05%,0.10%,0.15%,0.20%)hBN改性聚氨酯丙烯酸酯(hBN/PUA)复合材料,研究了hBN含量对复合材料力学性能和干摩擦磨损性能的影响。结果... 采用硅烷偶联剂KH550对六方氮化硼(hBN)纳米颗粒进行表面改性处理,利用立体光刻技术制备不同质量分数(0.05%,0.10%,0.15%,0.20%)hBN改性聚氨酯丙烯酸酯(hBN/PUA)复合材料,研究了hBN含量对复合材料力学性能和干摩擦磨损性能的影响。结果表明:随着hBN含量的增加,复合材料的拉伸和弯曲强度均先增再降,稳定摩擦因数和磨损质量损失均先减后增;当hBN的质量分数为0.10%时,复合材料的拉伸强度和弯曲强度最大,相较于纯PUA分别提高35.87%和36.92%,稳定摩擦因数和磨损质量损失均最小,与纯PUA相比分别降低31.03%和45.83%,此时复合材料的力学性能和耐磨性能最佳。当hBN的质量分数不高于0.10%时,hBN颗粒均匀地分布在PUA基体中,阻碍裂纹扩展,因此复合材料强度和耐磨性提高;当hBN质量分数大于0.10%时,hBN颗粒发生团聚,导致应力集中,强度和耐磨性能降低。 展开更多
关键词 hbn/PUA复合材料 拉伸性能 弯曲性能 干摩擦磨损性能
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氮流量对六方氮化硼(hBN)薄膜结构和力学性能的影响
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作者 张丽红 张斌 +3 位作者 高凯雄 于元烈 唐宏亮 张俊彦 《表面技术》 EI CAS CSCD 北大核心 2024年第5期52-59,共8页
目的研究磁控溅射过程氮气(N_(2))流量对六方氮化硼(hBN)薄膜结构和力学性能的影响,为设计新型结构hBN薄膜提供新思路。方法利用中频电源磁控溅射硼靶,调节不同N_(2)流量(6、12、18、24、30、36 mL/min),沉积4 h后得到hBN薄膜,使用表征... 目的研究磁控溅射过程氮气(N_(2))流量对六方氮化硼(hBN)薄膜结构和力学性能的影响,为设计新型结构hBN薄膜提供新思路。方法利用中频电源磁控溅射硼靶,调节不同N_(2)流量(6、12、18、24、30、36 mL/min),沉积4 h后得到hBN薄膜,使用表征工具分析N_(2)流量对hBN薄膜的组成、微观结构、表面形貌以及力学性能的影响。最后使用透射电子显微镜和选区电子衍射对所制备薄膜的纳米晶粒尺寸和晶体点阵结构进行分析。结果XRD结果显示,薄膜物相主要为hBN。XPS结果说明,所制备薄膜为富硼hBN薄膜。薄膜的硬度和弹性模量随N_(2)引入量的增加呈现先下降、后上升的趋势,最大硬度可达7.21 GPa,对应弹性模量为116.78 GPa。薄膜最低的硬度值为1.2 GPa,弹性模量为32.68 GPa。薄膜弹性破坏应变(H/E*)和塑性变形抗力(H3/E*2)随N_(2)引入量的增加也呈现先上升、后下降的趋势,硬度最高薄膜对应的H/E*值为6.414×10^(-2),H3/E*2值为29.27×10^(-3)GPa,最低硬度值对应的H/E*值为3.819×10^(-2),H3/E*2值为1.77×10^(-3)GPa。透射结果显示,当N_(2)引入量从6 mL/min逐渐增加到36 mL/min时,薄膜微观结构由结晶较差的卷曲结构过渡到局部纳米晶结构,最后形成结晶性较好的卷曲结构,并再次证明所制备薄膜为hBN。结论在中频磁控溅射沉积hBN薄膜时,通过调整N_(2)流量可以有效调节薄膜的特殊组成,使结构发生转变,进而影响薄膜的力学性能。 展开更多
关键词 hbn薄膜 B靶 N_(2)流量 力学性能 卷曲结构
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Strong metal–support interaction boosts the electrocatalytic hydrogen evolution capability of Ru nanoparticles supported on titanium nitride 被引量:1
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作者 Xin Wang Xiaoli Yang +7 位作者 Guangxian Pei Jifa Yang Junzhe Liu Fengwang Zhao Fayi Jin Wei Jiang Haoxi Ben Lixue Zhang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第1期245-254,共10页
Ruthenium(Ru)has been regarded as one of the most promising alternatives to substitute Pt for catalyzing alkaline hydrogen evolution reaction(HER),owing to its inherent high activity and being the cheapest platinum-gr... Ruthenium(Ru)has been regarded as one of the most promising alternatives to substitute Pt for catalyzing alkaline hydrogen evolution reaction(HER),owing to its inherent high activity and being the cheapest platinum-group metal.Herein,based on the idea of strong metal–support interaction(SMSI)regulation,Ru/TiN catalysts with different degrees of TiN overlayer over Ru nanoparticles were fabricated,which were applied to the alkaline electrolytic water.Characterizations reveal that the TiN overlayer would gradually encapsulate the Ru nanoparticles and induce more electron transfer from Ru nanoparticles to TiN support by the Ru–N–Ti bond as the SMSI degree increased.Further study shows that the exposed Ru–TiN interfaces greatly promote the H_(2) desorption capacity.Thus,the Ru/TiN-300 with a moderate SMSI degree exhibits excellent HER performance,with an overpotential of 38 mV at 10 mA cm^(−2).Also,due to the encapsulation role of TiN overlayer on Ru nanoparticles,it displays super long-term stability with a very slight potential change after 24 h.This study provides a deep insight into the influence of the SMSI effect between Ru and TiN on HER and offers a novel approach for preparing efficient and stable HER electrocatalysts through SMSI engineering. 展开更多
关键词 electronic structure hydrogen evolution reaction RUTHENIUM strong metal-support interaction titanium nitride
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Hollow Ni Mo-based nitride heterojunction with super-hydrophilic/aerophobic surface for efficient urea-assisted hydrogen production 被引量:1
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作者 Yuying Fan Ying Gu +3 位作者 Dongxu Wang Yanqing Jiao Aiping Wu Chungui Tian 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期428-439,I0009,共13页
Hydrogen evolution reaction(HER)and urea oxidation reaction(UOR)are key reactions of the watercycling associated catalytic process/device.The design of catalysts with a super-hydrophilic/aerophobic structure and optim... Hydrogen evolution reaction(HER)and urea oxidation reaction(UOR)are key reactions of the watercycling associated catalytic process/device.The design of catalysts with a super-hydrophilic/aerophobic structure and optimized electron distribution holds great promise.Here,we have designed a threedimensional(3D)hollow Ni/NiMoN hierarchical structure with arrayed-sheet surface based on a onepot hydrothermal route for efficient urea-assisted HER based on a simple hydrothermal process.The Ni/NiMoN catalyst exhibits super-hydrophilic/aerophobic properties with a small droplet contact angle of 6.07°and an underwater bubble contact angle of 155.7°,thus facilitating an escape of bubbles from the electrodes.Density functional theory calculations and X-ray photoelectron spectroscopy results indicate the optimized electronic structure at the interface of Ni and NiMoN,which can promote the adsorption/desorption of reactants and intermediates.The virtues combining with a large specific surface area endow Ni/NiMoN with efficient catalytic activity of low potentials of 25 mV for HER and 1.33 V for UOR at10 mA cm^(-2).The coupled HER and UOR system demonstrates a low cell voltage of 1.42 V at 10 mA cm^(-2),which is approximately 209 mV lower than water electrolysis. 展开更多
关键词 Hydrogen evolution Transition metal nitrides Hollow heterojunctions Urea electrooxidation Super hydrophilic/aerophobic
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Flexible and Robust Functionalized Boron Nitride/Poly(p‑Phenylene Benzobisoxazole)Nanocomposite Paper with High Thermal Conductivity and Outstanding Electrical Insulation 被引量:1
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作者 Lin Tang Kunpeng Ruan +3 位作者 Xi Liu Yusheng Tang Yali Zhang Junwei Gu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第2期423-437,共15页
With the rapid development of 5G information technology,thermal conductivity/dissipation problems of highly integrated electronic devices and electrical equipment are becoming prominent.In this work,“high-temperature... With the rapid development of 5G information technology,thermal conductivity/dissipation problems of highly integrated electronic devices and electrical equipment are becoming prominent.In this work,“high-temperature solid-phase&diazonium salt decomposition”method is carried out to prepare benzidine-functionalized boron nitride(m-BN).Subsequently,m-BN/poly(pphenylene benzobisoxazole)nanofiber(PNF)nanocomposite paper with nacremimetic layered structures is prepared via sol–gel film transformation approach.The obtained m-BN/PNF nanocomposite paper with 50 wt%m-BN presents excellent thermal conductivity,incredible electrical insulation,outstanding mechanical properties and thermal stability,due to the construction of extensive hydrogen bonds andπ–πinteractions between m-BN and PNF,and stable nacre-mimetic layered structures.Itsλ∥andλ_(⊥)are 9.68 and 0.84 W m^(-1)K^(-1),and the volume resistivity and breakdown strength are as high as 2.3×10^(15)Ωcm and 324.2 kV mm^(-1),respectively.Besides,it also presents extremely high tensile strength of 193.6 MPa and thermal decomposition temperature of 640°C,showing a broad application prospect in high-end thermal management fields such as electronic devices and electrical equipment. 展开更多
关键词 Poly(p-phenylene-2 6-benzobisoxazole)nanofiber Boron nitride Thermal conductivity Electrical insulation
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热压烧结制备可磨耗封严Al2024/hBN复合材料及其性能
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作者 周利华 冯强 +7 位作者 何鹏江 潘超梅 罗浩 符乃科 朱杰 李志 宋信强 曾克里 《粉末冶金技术》 CAS CSCD 北大核心 2024年第4期396-402,共7页
采用热压烧结技术制备可磨耗封严Al2024/hBN复合材料,研究了球磨时间对复合材料微观组织和力学性能的影响。结果表明,通过热压烧结技术制备的Al2024/hBN复合材料具有较高的密度和硬度,分别达到2.52g·cm^(-3)和HR15Y 90以上。随着... 采用热压烧结技术制备可磨耗封严Al2024/hBN复合材料,研究了球磨时间对复合材料微观组织和力学性能的影响。结果表明,通过热压烧结技术制备的Al2024/hBN复合材料具有较高的密度和硬度,分别达到2.52g·cm^(-3)和HR15Y 90以上。随着球磨时间的增加,热压烧结样品微观组织发生显著变化,由颗粒状变为层片组织结构;摩擦系数和体积磨损量降低,最低达到0.32和2.3×10^(-3)mm^(3)·m^(-1)·N^(-1),三点弯曲力由1.2 kN提高到2.3 kN。 展开更多
关键词 Al2024/hbn 可磨耗封严 球磨 热压烧结 洛氏硬度
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基于磁控溅射法生长hBN薄膜的MSM型真空紫外探测器(特邀)
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作者 房万年 李强 +4 位作者 张启凡 陈冉升 李家兴 刘康康 云峰 《光子学报》 EI CAS CSCD 北大核心 2024年第7期21-30,共10页
针对目前大面积高质量六方氮化硼(hBN)薄膜的制备与转移存在均匀性、晶粒控制、无损转移等问题,采用射频磁控溅射技术成功在2英寸硅和蓝宝石介电衬底上沉积了hBN薄膜,拉曼光谱、X射线光电子能谱表征证实了薄膜具有明显的hBN特征。制备了... 针对目前大面积高质量六方氮化硼(hBN)薄膜的制备与转移存在均匀性、晶粒控制、无损转移等问题,采用射频磁控溅射技术成功在2英寸硅和蓝宝石介电衬底上沉积了hBN薄膜,拉曼光谱、X射线光电子能谱表征证实了薄膜具有明显的hBN特征。制备了hBN基金属-半导体-金属型光电探测器,并探究了电极材料、薄膜厚度以及叉指电极宽度和间距对探测性能的影响。优选出的Ni电极探测器具有极低的暗电流(<3 pA@100 V),对185 nm波长光具有明显光响应,响应度和比探测率分别为2.769 mA/W和2.969×10^(9)Jones。 展开更多
关键词 真空紫外探测 六方氮化硼 磁控溅射技术 金属-半导体-金属型光电探测器
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Recension of boron nitride phase diagram based on high-pressure and high-temperature experiments
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作者 Ruike Zhang Ruiang Guo +3 位作者 Qian Li Shuaiqi Li Haidong Long Duanwei He 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期450-457,共8页
Cubic boron nitride and hexagonal boron nitride are the two predominant crystalline structures of boron nitride.They can interconvert under varying pressure and temperature conditions.However,this transformation requi... Cubic boron nitride and hexagonal boron nitride are the two predominant crystalline structures of boron nitride.They can interconvert under varying pressure and temperature conditions.However,this transformation requires overcoming significant potential barriers in dynamics,which poses great difficulty in determining the c-BN/h-BN phase boundary.This study used high-pressure in situ differential thermal measurements to ascertain the temperature of h-BN/c-BN conversion within the commonly used pressure range(3-6 GPa)for the industrial synthesis of c-BN to constrain the P-T phase boundary of h-BN/c-BN in the pressure-temperature range as much as possible.Based on the analysis of the experimental data,it is determined that the relationship between pressure and temperature conforms to the following equation:P=a+1/bT.Here,P denotes the pressure(GPa)and T is the temperature(K).The coefficients are a=-3.8±0.8 GPa and b=229.8±17.1 GPa/K.These findings call into question existing high-pressure and high-temperature phase diagrams of boron nitride,which seem to overstate the phase boundary temperature between c-BN and h-BN.The BN phase diagram obtained from this study can provide critical temperature and pressure condition guidance for the industrial synthesis of c-BN,thus optimizing synthesis efficiency and product performance. 展开更多
关键词 hexagonal boron nitride phase diagram high temperature and high pressure cubic boron nitride phase transition differential thermal analysis
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Enhanced thermal conductivity and mechanical properties of boron nitride@polymethylacrylimide/epoxy composites with self-assembled stable three-dimensional network
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作者 Yang Wang Ye Fang +3 位作者 Xudong Yang Hongmin Cong Zhengbai Zhao Chao Yan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第11期230-238,共9页
Constructing a three-dimensional(3D)network of fillers with high thermal conductivity is considered to be an effective strategy to obtain ideal thermal management materials(TMMs).However,3D filler network is often dis... Constructing a three-dimensional(3D)network of fillers with high thermal conductivity is considered to be an effective strategy to obtain ideal thermal management materials(TMMs).However,3D filler network is often disrupted by the subsequent processing and forming processes,and it is difficult to incorporate high levels of fillers into lyophilized aerogels,which is a key factor limiting their widespread use.In this work,boron nitride@polymethylacrylimide/epoxy(BN@PMI/EP)composites with a stable 3D BN network were prepared by freeze-drying and hot-pressing.A water-soluble copolymer quaternary ammonium salt has been synthesized by the solution polymerization.A BN@PMI aerogel was obtained by the freeze-drying of ammonium salt and BN solution and thermal imidization.The BN@PMI aerogel has a six-membered imine ring structure that can be loaded with a high content of BN,which ensures the stability of the 3D BN network structure and facilitates the subsequent impregnation of EP in vacuum,which is one of the innovations of this work.The stable and complete 3D BN network leads to the enhancement of thermal conductivity,and the out-of-plane and in-plane thermal conductivities of BN@PMI/EP reach 1.21 W·m^(-1)·K^(-1)and 2.76 W·m^(-1)·K^(-1)at a BN mass loading of 40%,respectively.Meanwhile,the excellent mechanical properties and results of finite-element simulation and actual experiments confirm that BN@PMI/EP is a potential TMM. 展开更多
关键词 Polymethylacrylimide Heat transfer Mechanical properties Boron nitride COMPOSITES
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Tuning the crystallinity of titanium nitride on copper-embedded carbon nanofiber interlayers for accelerated electrochemical kinetics in lithium-sulfur batteries
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作者 Yinyu Xiang Liqiang Lu +4 位作者 Feng Yan Debarun Sengupta Petra Rudolf Ajay Giri Prakash Kottapalli Yutao Pei 《Carbon Energy》 SCIE EI CAS CSCD 2024年第6期40-55,共16页
The development of lithium-sulfur(Li-S)batteries is hindered by the disadvantages of shuttling of polysulfides and the sluggish redox kinetics of the conversion of sulfur species during discharge and charge.Herein,the... The development of lithium-sulfur(Li-S)batteries is hindered by the disadvantages of shuttling of polysulfides and the sluggish redox kinetics of the conversion of sulfur species during discharge and charge.Herein,the crystallinities of a titanium nitride(TiN)film on copper-embedded carbon nanofibers(Cu-CNFs)are regulated and the nanofibers are used as interlayers to resolve the aforementioned crucial issues.A low-crystalline TiN-coated Cu-CNF(L-TiN-Cu-CNF)interlayer is compared with its highly crystalline counterpart(H-TiN-Cu-CNFs).It is demonstrated that the L-TiN coating not only strengthens the chemical adsorption toward polysulfides but also greatly accelerates the electrochemical conversion of polysulfides.Due to robust carbon frameworks and enhanced kinetics,impressive highrate performance at 2 C(913 mAh g^(-1)based on sulfur)as well as remarkable cyclic stability up to 300 cycles(626 mAh g^(-1))with capacity retention of 46.5%is realized for L-TiN-Cu-CNF interlayer-configured Li-S batteries.Even under high loading(3.8 mg cm^(-2))of sulfur and relatively lean electrolyte(10μL electrolyte per milligram sulfur)conditions,the Li-S battery equipped with L-TiN-Cu-CNF interlayers delivers a high capacity of 1144 mAh g^(-1)with cathodic capacity of 4.25 mAh cm^(-2)at 0.1 C,providing a potential pathway toward the design of multifunctional interlayers for highly efficient Li-S batteries. 展开更多
关键词 CRYSTALLINITY electrochemical kinetics INTERLAYER lithium-sulfur batteries titanium nitride
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Insight into structure evolution of carbon nitrides and its energy conversion as luminescence
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作者 Hao Zhang Jingwei Zhang +4 位作者 Wenjie Chen Minjia Tao Xianguang Meng Yuanjian Zhang Guifu Zuo 《Carbon Energy》 SCIE EI CAS CSCD 2024年第2期37-60,共24页
A series of carbon nitride(CN)materials represented by graphitic carbon nitride(g-C_(3)N_(4))have been widely used in bioimaging,biosensing,and other fields in recent years due to their nontoxicity,low cost,and high l... A series of carbon nitride(CN)materials represented by graphitic carbon nitride(g-C_(3)N_(4))have been widely used in bioimaging,biosensing,and other fields in recent years due to their nontoxicity,low cost,and high luminescent quantum efficiency.What is more attractive is that the luminescent properties such as wavelength and intensity can be regulated by controlling the structure at the molecular level.Hence,it is time to summarize the related research on CN structural evolution and make a prospect on future developments.In this review,we first summarize the research history and multiple structural evolution of CN.Then,the progress of improving the luminescence performance of CN through structural evolution was discussed.Significantly,the relationship between CN structure evolution and energy conversion in the forms of photoluminescence,chemiluminescence,and electrochemiluminescence was reviewed.Finally,key challenges and opportunities such as nanoscale dispersion strategy,luminous efficiency improving methods,standardization evaluation,and macroscopic preparation of CN are highlighted. 展开更多
关键词 carbon nitride CHEMILUMINESCENCE ELECTROCHEMILUMINESCENCE energy conversion PHOTOLUMINESCENCE structural evolution
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Boron Nitride-Integrated Lithium Batteries:Exploring Innovations in Longevity and Performance
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作者 Shayan Angizi Sayed Ali Ahmad Alem +3 位作者 Mahdi Torabian Maryam Khalaj Dmitri Golberg Amir Pakdel 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第6期13-40,共28页
The current global warming,coupled with the growing demand for energy in our daily lives,necessitates the development of more efficient and reliable energy storage devices.Lithium batteries(LBs)are at the forefront of... The current global warming,coupled with the growing demand for energy in our daily lives,necessitates the development of more efficient and reliable energy storage devices.Lithium batteries(LBs)are at the forefront of emerging power sources addressing these challenges.Recent studies have shown that integrating hexagonal boron nitride(h-BN)nanomaterials into LBs enhances the safety,longevity,and electrochemical performance of all LB components,including electrodes,electrolytes,and separators,thereby suggesting their potential value in advancing eco-friendly energy solutions.This review provides an overview of the most recent applications of h-BN nanomaterials in LBs.It begins with an informative introduction to h-BN nanomaterials and their relevant properties in the context of LB applications.Subsequently,it addresses the challenges posed by h-BN and discusses existing strategies to overcome these limitations,offering valuable insights into the potential of BN nanomaterials.The review then proceeds to outline the functions of h-BN in LB components,emphasizing the molecular-level mechanisms responsible for performance improvements.Finally,the review concludes by presenting the current challenges and prospects of integrating h-BN nanomaterials into battery research. 展开更多
关键词 ELECTRODE ELECTROLYTE hexagonal boron nitride lithium battery SEPARATOR
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3D-printable Boron Nitride/Polyacrylic Hydrogel Composites with High Thermal Conductivities
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作者 DAI Jialei XUE Bingyu +5 位作者 QIAN Qi HE Wenhao ZHU Chenglong LEI Liwen WANG Kun XIE Jingjing 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第5期1303-1310,共8页
Polyacrylic acid(PAA)hydrogel composites with different hexagonal boron nitride(h-BN)fillers were synthesized and successfully 3D-printed while their thermal conductivity was systematically studied.With the content of... Polyacrylic acid(PAA)hydrogel composites with different hexagonal boron nitride(h-BN)fillers were synthesized and successfully 3D-printed while their thermal conductivity was systematically studied.With the content of h-BN increasing from 0.1 wt%to 0.3 wt%,the thermal conductivity of the 3D-printed composites has been improved.Moreover,through the shear force given by the 3D printer,a complete thermal conductivity path is obtained inside the hydrogel,which significantly improves the thermal conductivity of the h-BN hydrogel composites.The maximum thermal conductivity is 0.8808 W/(m·K),leading to a thermal conductive enhancement of 1000%,compared with the thermal conductivity of pure PAA hydrogels.This study shows that using h-BN fillers can effectively and significantly improve the thermal conductivity of hydrogelbased materials while its 3D-printable ability has been maintained. 展开更多
关键词 hydrogel composites boron nitride 3D printing thermal conductivity
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Theoretical insights into the structures and fundamental properties of pnictogen nitrides
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作者 Jingjing Wang Panlong Kong +3 位作者 Dingmei Zhang Defang Gao Zaifu Jiang Wei Dai 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期474-479,共6页
Recent experimental advancements reported a chemical reaction between antimony and nitrogen under high temperature and high pressure,yielding crystalline antimony nitride(Sb_(3)N_(5))with an orthorhombic structure.Mot... Recent experimental advancements reported a chemical reaction between antimony and nitrogen under high temperature and high pressure,yielding crystalline antimony nitride(Sb_(3)N_(5))with an orthorhombic structure.Motivated by this statement,we calculate the stability,elastic properties,electronic properties and energy density of the Cmc2_(1) structure for pnictogen nitrides X_(3)N_(5)(X=P,As,Sb,and Bi)using first-principles calculations combined with particle swarm optimization algorithms.Calculations of formation enthalpies,elastic constants and phonon spectra show that P_(3)N_(5),As_(3)N_(5) and Sb_(3)N_(5) are thermodynamically,mechanically and kinetically stable at 35 GPa,whereas Bi_(3)N_(5) is mechanically and kinetically stable but thermodynamically unstable.The computed electronic density of states shows strong covalent bonding between the N atoms and the phosphorus group atoms in the four compounds,confirmed by the calculated electronic localization function.We also calculate the energy densities for Sb_(3)N_(5) and find it to be a potentially high-energy-density material. 展开更多
关键词 pnictogen nitrides structural stability electronic property energy density
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Nanoscale cathodoluminescence spectroscopy probing the nitride quantum wells in an electron microscope
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作者 刘哲彤 刘秉尧 +8 位作者 梁冬冬 李晓梅 李晓敏 陈莉 朱瑞 徐军 魏同波 白雪冬 高鹏 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期144-149,共6页
To gain further understanding of the luminescence properties of multiquantum wells and the factors affecting them on a microscopic level,cathodoluminescence combined with scanning transmission electron microscopy and ... To gain further understanding of the luminescence properties of multiquantum wells and the factors affecting them on a microscopic level,cathodoluminescence combined with scanning transmission electron microscopy and spectroscopy was used to measure the luminescence of In_(0.15)Ga_(0.85)N five-period multiquantum wells.The lattice-composition-energy relationship was established with the help of energy-dispersive x-ray spectroscopy,and the bandgaps of In_(0.15)Ga_(0.85)N and GaN in multiple quantum wells were extracted by electron energy loss spectroscopy to understand the features of cathodoluminescence spectra.The luminescence differences between different periods of multiquantum wells and the effects of defects such as composition fluctuation and dislocations on the luminescence of multiple quantum wells were revealed.Our study establishing the direct relationship between the atomic structure of In_(x)Ga_(1-x)N multiquantum wells and photoelectric properties provides useful information for nitride applications. 展开更多
关键词 nitride multiquantum wells defect CATHODOLUMINESCENCE scanning transmission electron microscopy
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Preparation and Properties of Cu-Containing High-entropy Alloy Nitride Films by Magnetron Sputtering on Titanium Alloy
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作者 DENG Wanrong YANG Wei +5 位作者 YU Sen LAN Nan MA Xiqun WANG Liqun GAO Wei CHEN Jian 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第6期1586-1594,共9页
Magnetron sputtering deposition with regulated Cu target power was used for depositing Cu-containing high-entropy alloy nitride(Cu-(HEA)N)films on TC4 titanium alloy substrates.The microscopic morphologies,surface com... Magnetron sputtering deposition with regulated Cu target power was used for depositing Cu-containing high-entropy alloy nitride(Cu-(HEA)N)films on TC4 titanium alloy substrates.The microscopic morphologies,surface compositions,and thicknesses of the films were characterized using SEM+EDS;the anti-corrosion,wear resistance and antibacterial properties of the films in simulated seawater were investigated.The experimental results show that all four Cu-(HEA)N films are uniformly dense and contained nanoparticles.The film with Cu doping come into contact with oxygen in the air to form cuprous oxide.The corrosion resistance of the(HEA)N film without Cu doping on titanium alloy is better than the films with Cu doping.The Cu-(HEA)N film with Cu target power of 16 W shows the best wear resistance and antibacterial performance,which is attributed to the fact that Cu can reduce the coefficient of friction and exacerbate corrosion,and the formation of cuprous oxide has antibacterial properties.The findings of this study provide insights for engineering applications of TC4 in the marine field. 展开更多
关键词 titanium alloy high-entropy alloy nitride film magnetron sputtering properties
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Quantum-mechanical understanding on structure dependence of image potentials of single-walled boron nitride nanotubes
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作者 Yu Zhang Zhiman Zhang +2 位作者 Weiliang Wang Shaolin Zhang Haiming Huang 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第12期467-475,共9页
The recent discovery of field emission devices based on one-dimensional nanostructures has attracted much interest in emerging applications on next-generation flat panel displays,molecule-based sensors,and so forth.To... The recent discovery of field emission devices based on one-dimensional nanostructures has attracted much interest in emerging applications on next-generation flat panel displays,molecule-based sensors,and so forth.To achieve a comprehensive understanding of surface potentials at the nano-emitters during the tunneling process,in this study we systematically investigated the image potentials of single-walled boron nitride nanotubes with different edges,diameters and lengths in the frame of a composite first-principles calculation.The image potentials of zigzag single-walled boron nitride nanotubes are found to be dependent on the non-equivalent sides.Only the image potentials of isolated armchair single-walled boron nitride nanotube can be well fitted with the image potential of an ideal metal sphere of a size comparable to the tube diameter.On the contrary,the image potentials of zigzag and grounded armchair single-walled boron nitride nanotubes exhibit a strong length-dependence characteristic and are significantly different from that of an ideal metal sphere,which originates from the significant axial symmetry breaking of induced charge at the tip for the long tube.The correlation between the testing electron and electronic structure of single-walled boron nitride nanotube has also been discussed. 展开更多
关键词 boron nitride nanotubes quantum chemistry image potentials structure dependence
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Synthesis of boron nitride nanorod and its performance as a metalfree catalyst for oxidative desulfurization of diesel fuel
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作者 Tanaz Ghanadi Gholamreza Moradi Alimorad Rashidi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第4期120-132,共13页
In order to reduce the sulfur compounds in diesel fuel,boron nitride(BN)has been used as a novel metal-free catalyst in the present research.This nanocatalyst was synthesized via template-free approach followed by hea... In order to reduce the sulfur compounds in diesel fuel,boron nitride(BN)has been used as a novel metal-free catalyst in the present research.This nanocatalyst was synthesized via template-free approach followed by heating treatment at 900℃ in nitrogen atmosphere that the characteristics of the sample were identified by the X-ray diffraction,Fourier-transform infrared spectroscopy,Raman spectroscopy,field emission scanning electron microscopy,transmission electron microscopy,atomic force microscopy,and N2 adsorption-desorption isotherms.The results of structural and morphological analysis represented that BN has been successfully synthesized.The efficacy of the main operating parameters on the process was studied by using response surface methodology based on the Box-Behnken design method.The prepared catalyst showed high efficiency in oxidative desulfurization of diesel fuel with initial sulfur content of 8040 mg·kg^(-1)S.From statistical analysis,a significant quadratic model was obtained to predict the sulfur removal as a function of efficient parameters.The maximum efficiency of 72.4%was achieved under optimized conditions at oxidant/sulfur molar ratio of 10.2,temperature of 71℃,reaction time of 113 min,and catalyst dosage of 0.36 g.Also,the reusability of the BN was studied,and the result showed little reduction in activity of the catalyst after 10 times regeneration.Moreover,a plausible mechanism was proposed for oxidation of sulfur compounds on the surface of the catalyst.The present study shows that BN materials can be selected as promising metal-free catalysts for desulfurization process. 展开更多
关键词 DESULFURIZATION Boron nitride(BN)nanostructure Experimental design BoxeBehnken
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Effect of gamma-ray radiation on defect engineering and photocatalytic properties of boron nitride nanosheets
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作者 JIANG Zhiwen WANG Mozhen GE Xuewu 《辐射研究与辐射工艺学报》 CAS CSCD 2024年第6期67-77,共11页
The development of low-cost,abundant,and efficient non-metal catalysts has always been a research focus on photocatalytic hydrogen evolution reactions.Boron nitride nanosheet(BNNS),which is a promising non-metallic tw... The development of low-cost,abundant,and efficient non-metal catalysts has always been a research focus on photocatalytic hydrogen evolution reactions.Boron nitride nanosheet(BNNS),which is a promising non-metallic two-dimensional material,possesses remarkable properties.However,its inherently wide bandgap significantly limits their potential for visible-light-responsive catalysis,and conventional chemical methods struggle to overcome this limitation.In this study,we employed high-energy ionizing radiation to precisely regulate defect formation in BNNS at ambient temperature and pressure.The results showed that gamma-ray radiation markedly enhanced the efficiency of photocatalytic hydrogen production of the irradiated BNNS with increasing absorbed dose.The maximum hydrogen production rate of the samples reached 1033.7μmol/(g·h),which represents an increase of almost two orders of magnitude compared to commercial BNNS.The structural characterization also confirmed that the introduction of three-boron-center defects results in forming intermediate energy levels and improving the charge carrier separation efficiency of BNNS.This transformation converts BNNS from a wide bandgap semiconductor to a visible-light-responsive catalyst.This work not only provides a novel approach for the application of BNNS in visible-light photocatalysis,but also demonstrates the unique role of radiation technology in quantitatively regulating defects and improving catalytic activity. 展开更多
关键词 Boron nitride nanosheet Gamma-ray radiation Radiation effect Defect engineering PHOTOCATALYSIS
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