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Reshaping Li–Mg hybrid batteries:Epitaxial electrodeposition and spatial confinement on MgMOF substrates via the lattice‐matching strategy
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作者 Yongqin Wang Fulin Cheng +2 位作者 Jiawen Ji Chenyang Cai Yu Fu 《Carbon Energy》 SCIE EI CAS CSCD 2024年第8期248-261,共14页
The emergence of Li–Mg hybrid batteries has been receiving attention,owing to their enhanced electrochemical kinetics and reduced overpotential.Nevertheless,the persistent challenge of uneven Mg electrodeposition rem... The emergence of Li–Mg hybrid batteries has been receiving attention,owing to their enhanced electrochemical kinetics and reduced overpotential.Nevertheless,the persistent challenge of uneven Mg electrodeposition remains a significant impediment to their practical integration.Herein,we developed an ingenious approach that centered around epitaxial electrocrystallization and meticulously controlled growth of magnesium crystals on a specialized MgMOF substrate.The chosen MgMOF substrate demonstrated a robust affinity for magnesium and showed minimal lattice misfit with Mg,establishing the crucial prerequisites for successful heteroepitaxial electrocrystallization.Moreover,the incorporation of periodic electric fields and successive nanochannels within the MgMOF structure created a spatially confined environment that considerably promoted uniform magnesium nucleation at the molecular scale.Taking inspiration from the“blockchain”concept prevalent in the realm of big data,we seamlessly integrated a conductive polypyrrole framework,acting as a connecting“chain,”to interlink the“blocks”comprising the MgMOF cavities.This innovative design significantly amplified charge‐transfer efficiency,thereby increasing overall electrochemical kinetics.The resulting architecture(MgMOF@PPy@CC)served as an exceptional host for heteroepitaxial Mg electrodeposition,showcasing remarkable electrostripping/plating kinetics and excellent cycling performance.Surprisingly,a symmetrical cell incorporating the MgMOF@PPy@CC electrode demonstrated impressive stability even under ultrahigh current density conditions(10mAcm^(–2)),maintaining operation for an extended 1200 h,surpassing previously reported benchmarks.Significantly,on coupling the MgMOF@PPy@CC anode with a Mo_(6)S_(8) cathode,the assembled battery showed an extended lifespan of 10,000 cycles at 70 C,with an outstanding capacity retention of 96.23%.This study provides a fresh perspective on the rational design of epitaxial electrocrystallization driven by metal–organic framework(MOF)substrates,paving the way toward the advancement of cuttingedge batteries. 展开更多
关键词 epitaxial electrodeposition lattice‐matching strategy Li-Mg hybrid batteries MOF substrate spatial confinement
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Heavy Metal Detection in Soils by Laser Induced Breakdown Spectroscopy Using Hemispherical Spatial Confinement 被引量:6
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作者 孟德硕 赵南京 +5 位作者 马明俊 王寅 胡丽 余洋 方丽 刘文清 《Plasma Science and Technology》 SCIE EI CAS CSCD 2015年第8期632-637,共6页
Spatial confinement has great potential for Laser Induced Breakdown Spectroscopy (LIBS) instruments after it has been proven that it has the ability to enhance the LIBS signal strength and repeatability. In order to... Spatial confinement has great potential for Laser Induced Breakdown Spectroscopy (LIBS) instruments after it has been proven that it has the ability to enhance the LIBS signal strength and repeatability. In order to achieve in-situ measurement of heavy metals in farmland soils by LIBS, a hemispherical spatial confinement device is designed and used to collect plasma spectra, in which the optical fibers directly collect the breakdown spectroscopy of the soil samples. This device could effectively increase the stability of the spectrum intensity of soil. It also has other advantages, such as ease of installation, and its small and compact size. The relationship between the spectrum intensity and the laser pulse energy is studied for this device. It is found that the breakdown threshold is 160 cm-2, and when the laser fluence increases to 250 J/cm2, the spectrum intensity reaches its maximum. Four different kinds of laser pulse energy were set up and in each case the limits of detection of Cd, Cu, Ni, Pb and Zn were calculated. The results show that when the laser pulse fluence was 2.12 GW/cm2, we obtained the smallest limits of detection of these heavy metals, which are all under 10 mg/kg. This device can satisfy the needs of heavy metal in-situ detection, and in the next step it will be integrated into a portable LIBS instrument. 展开更多
关键词 laser induced breakdown spectroscopy hemispherical spatial confinement laser fiuence limit of detection
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Effect of cylindrical cavity height on laserinduced breakdown spectroscopy with spatial confinement 被引量:3
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作者 邵俊峰 王挺峰 +2 位作者 郭劲 陈安民 金明星 《Plasma Science and Technology》 SCIE EI CAS CSCD 2017年第2期89-94,共6页
In this paper, we present a study on the spatial confinement effect of laser-induced plasma with a cylindrical cavity in laser-induced breakdown spectroscopy (LIBS). The emission intensity with the spatial confineme... In this paper, we present a study on the spatial confinement effect of laser-induced plasma with a cylindrical cavity in laser-induced breakdown spectroscopy (LIBS). The emission intensity with the spatial confinement is dependent on the height of the confinement cavity. It is found that, by selecting the appropriate height of cylindrical cavity, the signal enhancement can be significantly increased. At the cylindrical cavity (diameter = 2 mm) with a height of 6 mm, the enhancement ratio has the maximum value (approximately 8.3), and the value of the relative standard deviation (RSD) (7.6%) is at a minimum, the repeatability of LIBS signal is best. The results indicate that the height of confinement cavity is very important for LIBS technique to reduce the limit of detection and improve the precision. 展开更多
关键词 LIBS spatial confinement cavity height signal enhancement
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Effect of distances between lens and sample surface on laser-induced breakdown spectroscopy with spatial confinement
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作者 Zhenhua JIANG Junfeng SHAO +4 位作者 Tingfeng WANG Jin GUO Dan ZHANG Anmin CHEN Mingxing JIN 《Plasma Science and Technology》 SCIE EI CAS CSCD 2018年第8期74-81,共8页
Spatial confinement can significantly enhance the spectral intensity of laser-induced plasma in air. It is attributed to the compression of plasma plume by the reflected shockwave. In addition,optical emission spectro... Spatial confinement can significantly enhance the spectral intensity of laser-induced plasma in air. It is attributed to the compression of plasma plume by the reflected shockwave. In addition,optical emission spectroscopy of laser-induced plasma can also be affected by the distance between lens and sample surface. In order to obtain the optimized spectral intensity, the distance must be considered. In this work, spatially confined laser-induced silicon plasma by using a Nd:YAG nanosecond laser at different distances between lens and sample surface was investigated.The laser energies were 12 mJ, 16 mJ, 20 mJ, and 24 mJ. All experiments were carried out in an atmospheric environment. The results indicated that the intensity of Si(I) 390.55 nm line firstly rose and then dropped with the increase of lens-to-sample distance. Moreover, the spectral peak intensity with spatial confinement was higher than that without spatial confinement. The enhancement ratio was approximately 2 when laser energy was 24 mJ. 展开更多
关键词 laser-induced breakdown spectroscopy LIBS spatial confinement distance of lens- to-sample signal enhancement
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Okra‑Like Multichannel TiO@NC Fibers Membrane with Spatial and Chemical Restriction on Shuttle‑Effect for Lithium–Sulfur Batteries 被引量:3
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作者 Shuai Li Jingchong Liu +9 位作者 Linlin Ma Li‑Juan Yu Lanlan Hou Dianming Li Songwei Gao Guichu Yue Zhimin Cui NüWang Xiaoxian Zhao Yong Zhao 《Advanced Fiber Materials》 SCIE EI 2023年第1期252-265,共14页
It is especially important to coordinately design the structure and composition of the host in lithium–sulfur batteries(LSBs)for improving its physicochemical adsorption and conversion of lithium polysulfide,which ca... It is especially important to coordinately design the structure and composition of the host in lithium–sulfur batteries(LSBs)for improving its physicochemical adsorption and conversion of lithium polysulfide,which can alleviate the harmful shuttle effect.Herein,a self-supporting multichannel nitrogen-doped carbon fibers membrane embedded with TiO nanoparticles(TiO@NC)was constructed as the electrode for LSBs.The inner channels and the embedded TiO nanoparticles offer spatial confinement and chemical binding for polysulfides,respectively.Moreover,the TiO nanoparticles have abundant oxygen vacancies that promote the conversion of polysulfides.In addition,the nitrogen-doped carbon skeleton can not only serve as highly conductive transportation paths for electrons,but also integrate with the inner channels to sustain the morphology and bear volume expansion during cycling processes.Therefore,the fabricated self-supporting quadruple-channel TiO@NC ultrathin fibers electrode exhibits a high initial specific capacity of 1342.8 mAh g^(-1)at 0.5 C and high-rate capability of 505.8 mAh g^(-1)at 4.0 C.In addition,it maintains 696.0 mAh g^(-1)over 500 cycles with only 0.059%capacity decay per cycle at the high current density of 2.0 C.The multichannel configuration combined with TiO nanoparticles provides a synergetic design strategy for fabricating high-performance electrodes in LSBs. 展开更多
关键词 MULTICHANNEL Electrospinning Hierarchical structure spatial confinement Chemical binding Lithium–sulfur battery
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Spatial confinement of zeolitic imidazolate framework deposits by porous carbon nanospheres for dual-atom catalyst towards high-performance oxygen reduction reaction 被引量:1
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作者 Jiayi Zhao Ping Li +6 位作者 Kaicai Fan Wenjie Wei Fenghong Lu Huimin Zhao Bin Li Lingbo Zong Lei Wang 《Nano Research》 SCIE EI CSCD 2023年第8期11464-11472,共9页
Dual atom catalysts(DACs),are promising electrocatalysts for oxygen reduction reaction(ORR)on account of the potential dual-atom active sites for the optimized adsorption of catalytic intermediates and the lower react... Dual atom catalysts(DACs),are promising electrocatalysts for oxygen reduction reaction(ORR)on account of the potential dual-atom active sites for the optimized adsorption of catalytic intermediates and the lower reaction energy barriers.Herein,spatial confinement strategy to fabricate DACs with well-defined Fe,Co dual-atom active site is proposed by implanting zeolitic imidazolate frameworks inside the pores of highly porous carbon nanospheres(Fe/Co-SAs-Nx-PCNSs).The atomically dispersed dual-atom active sites facilitate the adsorption/desorption of intermediates.Furthermore,the spatial confinement effect protects metal atoms aggregating.Benefiting from the rich accessible dual-atom active sites and boosted mass transport,we achieve remarkable ORR performance with half-wave potential up to 0.91 and 0.8 V(vs.reversible hydrogen electrode(RHE)),and long-term stability up to 10 h in both alkaline and acidic electrolytes.The remarkably enhanced ORR catalytic property of our as-developed DACs is in the rank of excellence for 1%.The as-developed rechargeable Zn-air battery(ZAB)with Fe/Co-SAs-Nx-PCNSs air cathode delivers ultrahigh power density of 216 mW·cm^(−2),outstanding specific capacity of 813 mAh·g^(−1),and promising cycling operation durability over 160 h.The flexible Zn-air battery also exhibits excellent specific capacity,cycling stability,and flexibility performance.This work opens up a new pathway for the multiscale design of efficient electrocatalysts with atomically dispersed multiple active sites. 展开更多
关键词 spatial confinement zeolitic imidazolate framework porous carbon nanospheres(PCNSs) dual-atom catalyst oxygen reduction reaction(ORR)
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Synthesis of cycloparaphenylene under spatial nanoconfinement
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作者 Jinjie Li Huixian Jin +4 位作者 Zhikun Shang Jie Wang Donglai Tian Yun Ding Aiguo Hu 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第6期298-300,共3页
Suzuki coupling reactions between symmetrical monomers were conducted in various mesoporous silica nanoreactors grafted with palladium catalysts,enabling the selective formation of[12]cycloparaphenylene precursor with... Suzuki coupling reactions between symmetrical monomers were conducted in various mesoporous silica nanoreactors grafted with palladium catalysts,enabling the selective formation of[12]cycloparaphenylene precursor with separate yield up to 25%in one-pot reactions,much higher than that in homogeneous reaction.The spatial nanoconfinement of the nanoreactors promotes the macrocyclization while limits the concomitant linear oligomer formation,offering more possibilities for the synthesis of macrocycles from symmetrical monomers in one-pot reaction. 展开更多
关键词 NANOREACTOR spatial confinement Cyclization reaction One-pot reaction Suzuki coupling reaction
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Lamella-like electrode with high Br_(2)-entrapping capability and activity enabled by adsorption and spatial confinement effects for brominebased flow battery 被引量:1
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作者 Luyin Tang Tianyu Li +1 位作者 Wenjing Lu Xianfeng Li 《Science Bulletin》 SCIE EI CSCD 2022年第13期1362-1371,M0004,共11页
Bromine-based flow batteries(Br-FBs)are well suitable for stationary energy storage owing to their high energy density and low cost.However,their power density and lifespan are limited by relatively low reaction kinet... Bromine-based flow batteries(Br-FBs)are well suitable for stationary energy storage owing to their high energy density and low cost.However,their power density and lifespan are limited by relatively low reaction kinetics of Br_(2)/Br-couple and serious self-discharge caused by bromine migration.Herein,lamella-like porous carbon nitride nanosheets(PCNS)with adsorption and spatial confinement effects are used to modify cathodes for Br-FBs.The large specific surface area and plentiful N-containing groups enable PCNS with excellent adsorption capacity,which captures bromine species into the pores on PCNS layers.The captured bromine species is subsequently confined in PCNS interlayers due to the strong interaction between bromine species and N-containing groups,thus effectively depressing bromine diffusion/migration.Moreover,the strong bromine adsorption capacity significantly improves the electrochemical activity of PCNS.Consequently,a zinc-bromine flow battery(ZBFB)employing PCNS-modified cathode achieves a high current density of 180 m A cm^(-2),with an ultra-high coulombic efficiency of 99.22%.It also exhibits better self-discharge performance and a long cycle life of 500 cycles.Furthermore,a complexing agent-free ZBFB is successfully realized based on the superior bromineentrapping/retaining capacity of the PCNS-modified cathode.Consequently,this work provides a promising strategy toward electrode modifications for high-performance and long-lifespan Br-FBs. 展开更多
关键词 Bromine-based flow battery Lamella-like electrode Bromine-entrapping capability Strong adsorption capacity spatial confinement effect
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Spatial confinement effects of laser-induced breakdown spectroscopy at reduced air pressures
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作者 Zhongqi Hao Zhiwei Deng +2 位作者 Li Liu Jiulin Shi Xingdao He 《Frontiers of Optoelectronics》 EI CSCD 2022年第2期35-44,共10页
Spatial confinement is a simple and cost-effective method for enhancing signal intensity and improving the detection sensitivity of laser-induced breakdown spectroscopy(LIBS).However,the spatial confinement effects of... Spatial confinement is a simple and cost-effective method for enhancing signal intensity and improving the detection sensitivity of laser-induced breakdown spectroscopy(LIBS).However,the spatial confinement effects of LIBS under different pressures remains a question to be studied,because the pressure of the ambient gas has a significant influence on the temporal and spatial evolution of plasma.In this study,spatial confinement effects of LIBS under a series of reduced air pressures were investigated experimentally,and the plasma characteristics under different air pressures were studied.The results show that the reduced air pressure can lead to both earlier onset and weakening of the enhancement effect of the spatial confinement on the LIBS line intensity.When the air pressure drops to 0.1 kPa,the enhancement effect of the emission intensity no longer comes from the compression of the reflected shock wave on the plasma,but from the cavity’s restriction of the plasma expansion space.In conclusion,the enhancement effect of spatial confinement technology on the LIBS is still effective when the pressure is reduced,which further expands the research and application field of spatial confinement technology. 展开更多
关键词 Laser-induced breakdown spectroscopy(LIBS) spatial confinement Plasma temperature Stark broadening
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