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Strong synergy between physical and chemical properties:Insight into optimization of atomically dispersed oxygen reduction catalysts 被引量:4
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作者 Yifan Zhang Linsheng Liu +4 位作者 Yuxuan Li Xueqin Mu Shichun Mu Suli Liu Zhihui Dai 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期36-49,共14页
Atomically dispersed catalysts exhibit significant influence on facilitating the sluggish oxygen reduction reaction(ORR)kinetics with high atom economy,owing to remarkable attributes including nearly 100%atomic utiliz... Atomically dispersed catalysts exhibit significant influence on facilitating the sluggish oxygen reduction reaction(ORR)kinetics with high atom economy,owing to remarkable attributes including nearly 100%atomic utilization and exceptional catalytic functionality.Furthermore,accurately controlling atomic physical properties including spin,charge,orbital,and lattice degrees of atomically dispersed catalysts can realize the optimized chemical properties including maximum atom utilization efficiency,homogenous active centers,and satisfactory catalytic performance,but remains elusive.Here,through physical and chemical insight,we review and systematically summarize the strategies to optimize atomically dispersed ORR catalysts including adjusting the atomic coordination environment,adjacent electronic orbital and site density,and the choice of dual-atom sites.Then the emphasis is on the fundamental understanding of the correlation between the physical property and the catalytic behavior for atomically dispersed catalysts.Finally,an overview of the existing challenges and prospects to illustrate the current obstacles and potential opportunities for the advancement of atomically dispersed catalysts in the realm of electrocatalytic reactions is offered. 展开更多
关键词 atomically dispersed catalysts Coordination environment Electronic orbitals Inter-site distance effect Oxygen reduction reaction
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Synthesis and Modulation of Low-Dimensional Transition Metal Chalcogenide Materials via Atomic Substitution 被引量:1
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作者 Xuan Wang Akang Chen +3 位作者 XinLei Wu Jiatao Zhang Jichen Dong Leining Zhang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期49-94,共46页
In recent years,low-dimensional transition metal chalcogenide(TMC)materials have garnered growing research attention due to their superior electronic,optical,and catalytic properties compared to their bulk counterpart... In recent years,low-dimensional transition metal chalcogenide(TMC)materials have garnered growing research attention due to their superior electronic,optical,and catalytic properties compared to their bulk counterparts.The controllable synthesis and manipulation of these materials are crucial for tailoring their properties and unlocking their full potential in various applications.In this context,the atomic substitution method has emerged as a favorable approach.It involves the replacement of specific atoms within TMC structures with other elements and possesses the capability to regulate the compositions finely,crystal structures,and inherent properties of the resulting materials.In this review,we present a comprehensive overview on various strategies of atomic substitution employed in the synthesis of zero-dimensional,one-dimensional and two-dimensional TMC materials.The effects of substituting elements,substitution ratios,and substitution positions on the structures and morphologies of resulting material are discussed.The enhanced electrocatalytic performance and photovoltaic properties of the obtained materials are also provided,emphasizing the role of atomic substitution in achieving these advancements.Finally,challenges and future prospects in the field of atomic substitution for fabricating low-dimensional TMC materials are summarized. 展开更多
关键词 Transition metal chalcogenides atomic substitution Ion exchange Low-dimensional materials Controllable synthesis
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A frequency servo SoC with output power stabilization loop technology for miniaturized atomic clocks 被引量:1
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作者 Hongyang Zhang Xinlin Geng +3 位作者 Zonglin Ye Kailei Wang Qian Xie Zheng Wang 《Journal of Semiconductors》 EI CAS CSCD 2024年第6期13-22,共10页
A frequency servo system-on-chip(FS-SoC)featuring output power stabilization technology is introduced in this study for high-precision and miniaturized cesium(Cs)atomic clocks.The proposed power stabilization loop(PSL... A frequency servo system-on-chip(FS-SoC)featuring output power stabilization technology is introduced in this study for high-precision and miniaturized cesium(Cs)atomic clocks.The proposed power stabilization loop(PSL)technique,incorporating an off-chip power detector(PD),ensures that the output power of the FS-SoC remains stable,mitigating the impact of power fluctuations on the atomic clock's stability.Additionally,a one-pulse-per-second(1PPS)is employed to syn-chronize the clock with GPS.Fabricated using 65 nm CMOS technology,the measured phase noise of the FS-SoC stands at-69.5 dBc/Hz@100 Hz offset and-83.9 dBc/Hz@1 kHz offset,accompanied by a power dissipation of 19.7 mW.The Cs atomic clock employing the proposed FS-SoC and PSL obtains an Allan deviation of 1.7×10^(-11) with 1-s averaging time. 展开更多
关键词 CMOS technology atomic clock phase-locked loop output power stabilization 1PPS
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Atomically dispersed Ni electrocatalyst for superior urea-assisted water splitting 被引量:1
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作者 Fang Luo Shuyuan Pan +3 位作者 Yuhua Xie Chen Li Yingjie Yu Zehui Yang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期1-6,I0002,共7页
Urea oxidation reaction(UOR) has been selected as substitution for oxygen evolution reaction ascribing to its low thermodynamic voltage as well as utilization of nickel as electrocatalyst.Herein,we report the formatio... Urea oxidation reaction(UOR) has been selected as substitution for oxygen evolution reaction ascribing to its low thermodynamic voltage as well as utilization of nickel as electrocatalyst.Herein,we report the formation of nickel single atoms(Ni-SAs) as exceptional bifunctional electrocatalyst toward UOR and hydrogen evolution reaction(HER) in urea-assisted water splitting.In UOR catalysis,Ni-SAs perform a superior catalytic performance than Ni-NP/NC and Pt/C ascribing to the formation of HOO-Ni-N_(4) structure evidenced by in-situ Raman spectroscopy,corresponding to a boosted mass activity by 175-fold at 1.4 V vs.RHE than Ni-NP/NC.Furthermore,Ni-SAs requires only 450 mV overpotential to obtain HER current density of 500 mA cm^(-2).136 mA cm^(-2) is achieved in urea-assisted water splitting at1.7 V for Ni-SAs,boosted by 5.7 times than Pt/C-IrO_(2) driven water splitting. 展开更多
关键词 Urea oxidation reaction Hydrogen evolution reaction Nickel single atoms Water splitting
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Building Feedback-Regulation System Through Atomic Design for Highly Active SO_(2)Sensing 被引量:1
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作者 Xin Jia Panzhe Qiao +8 位作者 Xiaowu Wang Muyu Yan Yang Chen Bao-Li An Pengfei Hu Bo Lu Jing Xu Zhenggang Xue Jiaqiang Xu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第7期343-357,共15页
Reasonably constructing an atomic interface is pronouncedly essential for surface-related gas-sensing reaction.Herein,we present an ingen-ious feedback-regulation system by changing the interactional mode between sing... Reasonably constructing an atomic interface is pronouncedly essential for surface-related gas-sensing reaction.Herein,we present an ingen-ious feedback-regulation system by changing the interactional mode between single Pt atoms and adjacent S species for high-efficiency SO_(2)sensing.We found that the single Pt sites on the MoS_(2)surface can induce easier volatiliza-tion of adjacent S species to activate the whole inert S plane.Reversely,the activated S species can provide a feedback role in tailoring the antibonding-orbital electronic occupancy state of Pt atoms,thus creating a combined system involving S vacancy-assisted single Pt sites(Pt-Vs)to synergistically improve the adsorption ability of SO_(2)gas molecules.Further-more,in situ Raman,ex situ X-ray photoelectron spectroscopy testing and density functional theory analysis demonstrate the intact feedback-regulation system can expand the electron transfer path from single Pt sites to whole Pt-MoS_(2)supports in SO_(2)gas atmosphere.Equipped with wireless-sensing modules,the final Pt1-MoS_(2)-def sensors array can further realize real-time monitoring of SO_(2)levels and cloud-data storage for plant growth.Such a fundamental understanding of the intrinsic link between atomic interface and sensing mechanism is thus expected to broaden the rational design of highly effective gas sensors. 展开更多
关键词 Feedback-regulation system atomic interface SO_(2)sensor Single-atom sensing mechanism Intelligent-sensing array
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Precise construction of RuPt dual single-atomic sites to optimize oxygen electrocatalytic behaviors for high-performance Zn-air batteries
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作者 Xiaolin Hu Zhenkun Wu Chaohe Xu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期520-528,I0011,共10页
The development of redox bifunctional electrocatalysts with high performance,low cost,and long lifetimes is essential for achieving clean energy goals.This study proposed an atom capture strategy for anchoring dual si... The development of redox bifunctional electrocatalysts with high performance,low cost,and long lifetimes is essential for achieving clean energy goals.This study proposed an atom capture strategy for anchoring dual single atoms(DSAs)in a zinc-zeolitic imidazolate framework(Zn-ZIF),followed by calcination under an N_(2) atmosphere to synthesize ruthenium-platinum DSAs supported on a nitrogendoped carbon substrate(RuPt DSAs-NC).Theoretical calculations showed that the degree of Ru 5dxz-~*O 2p_x orbital hybridization was high when^(*)O was adsorbed at the Ru site,indicating enhanced covalent hybridization of metal sites and oxygen ligands,which benefited the adsorption of intermediate species.The presence of the RuPtN_6 active center optimized the absorption-desorption behavior of intermediates,improving the electrocatalytic performance of the oxygen reduction reaction(ORR)and the oxygen evolution reaction(DER),RuPt DSAs-NC exhibited a 0.87 V high half-wave potential and a 268 mV low overpotential at 10 mA cm^(-2)in an alkaline environment.Furthermore,rechargeable zinc-air batteries(ZABs)achieved a peak power density of 171 MW cm^(-2).The RuPt DSAs-NC demonstrated long-term cycling for up to 500 h with superior round-trip efficiency.This study provided an effective structural design strategy to construct DSAs active sites for enhanced electrocata lytic performance. 展开更多
关键词 Dual single atoms catalysts atom capture Oxygen reduction reaction Oxygen evolution reaction Rechargeable Zn-air batteries
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Atomic layer deposition in advanced display technologies:from photoluminescence to encapsulation
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作者 Rong Chen Kun Cao +4 位作者 Yanwei Wen Fan Yang Jian Wang Xiao Liu Bin Shan 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第2期65-82,共18页
Driven by the growing demand for next-generation displays,the development of advanced luminescent materials with exceptional photoelectric properties is rapidly accelerating,with such materials including quantum dots ... Driven by the growing demand for next-generation displays,the development of advanced luminescent materials with exceptional photoelectric properties is rapidly accelerating,with such materials including quantum dots and phosphors,etc.Nevertheless,the primary challenge preventing the practical application of these luminescent materials lies in meeting the required durability standards.Atomic layer deposition(ALD)has,therefore,been employed to stabilize luminescent materials,and as a result,flexible display devices have been fabricated through material modification,surface and interface engineering,encapsulation,cross-scale manufacturing,and simulations.In addition,the appropriate equipment has been developed for both spatial ALD and fluidized ALD to satisfy the low-cost,high-efficiency,and high-reliability manufacturing requirements.This strategic approach establishes the groundwork for the development of ultra-stable luminescent materials,highly efficient light-emitting diodes(LEDs),and thin-film packaging.Ultimately,this significantly enhances their potential applicability in LED illumination and backlighted displays,marking a notable advancement in the display industry. 展开更多
关键词 atomic layer deposition DISPLAY LUMINESCENT ENCAPSULATION
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Tailoring local structures of atomically dispersed copper sites for highly selective CO_(2) electroreduction
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作者 Kyung‐Jong Noh Byoung Joon Park +5 位作者 Ying Wang Yejung Choi Sang‐Hoon You Yong‐Tae Kim Kug‐Seung Lee Jeong Woo Han 《Carbon Energy》 SCIE EI CAS CSCD 2024年第4期79-90,共12页
Atomically‐dispersed copper sites coordinated with nitrogen‐doped carbon(Cu–N–C)can provide novel possibilities to enable highly selective and active electrochemical CO_(2) reduction reactions.However,the construc... Atomically‐dispersed copper sites coordinated with nitrogen‐doped carbon(Cu–N–C)can provide novel possibilities to enable highly selective and active electrochemical CO_(2) reduction reactions.However,the construction of optimal local electronic structures for nitrogen‐coordinated Cu sites(Cu–N_(4))on carbon remains challenging.Here,we synthesized the Cu–N–C catalysts with atomically‐dispersed edge‐hosted Cu–N_(4) sites(Cu–N_(4)C_(8))located in a micropore between two graphitic sheets via a facile method to control the concentration of metal precursor.Edge‐hosted Cu–N_(4)C_(8) catalysts outperformed the previously reported M–N–C catalysts for CO_(2)‐to‐CO conversion,achieving a maximum CO Faradaic efficiency(FECO)of 96%,a CO current density of–8.97 mA cm^(–2) at–0.8 V versus reversible hydrogen electrode(RHE),and over FECO of 90%from–0.6 to–1.0 V versus RHE.Computational studies revealed that the micropore of the graphitic layer in edge‐hosted Cu–N_(4)C_(8) sites causes the d‐orbital energy level of the Cu atom to shift upward,which in return decreases the occupancy of antibonding states in the*COOH binding.This research suggests new insights into tailoring the locally coordinated structure of the electrocatalyst at the atomic scale to achieve highly selective electrocatalytic reactions. 展开更多
关键词 atomic local structure density functional theory electrochemical CO_(2)reduction metal nitrogen‐doped carbon single‐atom catalyst
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Methanol steam reforming for hydrogen production driven by an atomically precise Cu catalyst
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作者 Weigang Hu Haoqi Liu +7 位作者 Yuankun Zhang Jiawei Ji Guangjun Li Xiao Cai Xu Liu Wen Wu Xu Weiping Ding Yan Zhu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第7期1079-1084,共6页
Plasmon-induced hot-electron transfer from metal nanostructures is being intensely pursed in current photocatalytic research,however it remains elusive whether molecular-like metal clusters with excitonic behavior can... Plasmon-induced hot-electron transfer from metal nanostructures is being intensely pursed in current photocatalytic research,however it remains elusive whether molecular-like metal clusters with excitonic behavior can be used as light-harvesting materials in solar energy utilization such as photocatalytic methanol steam reforming.In this work,we report an atomically precise Cu_(13)cluster protected by dual ligands of thiolate and phosphine that can be viewed as the assembly of one top Cu atom and three Cu_(4)tetrahedra.The Cu_(13)H_(10)(SR)_(3)(PR’_(3))_(7)(SR=2,4-dichlorobenzenethiol,PR’_(3)=P(4-FC_(6)H_(4))_(3))cluster can give rise to highly efficient light-driven activity for methanol steam reforming toward H_(2)production. 展开更多
关键词 NANOCLUSTER PHOTOCATALYSIS Methanol steam reforming atomically precise Copper catalyst
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Unveiling the early stage evolution of local atomic structures in the crystallization process of a metallic glass
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作者 马琳 杨晓东 +2 位作者 杨锋 周鑫嘉 武振伟 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期58-64,共7页
The early stage evolution of local atomic structures in a multicomponent metallic glass during its crystallization process has been investigated via molecular dynamics simulation.It is found that the initial thermal s... The early stage evolution of local atomic structures in a multicomponent metallic glass during its crystallization process has been investigated via molecular dynamics simulation.It is found that the initial thermal stability and earliest stage evolution of the local atomic clusters show no strong correlation with their initial short-range orders,and this leads to an observation of a novel symmetry convergence phenomenon,which can be understood as an atomic structure manifestation of the ergodicity.Furthermore,in our system we have quantitatively proved that the crucial factor for the thermal stability against crystallization exhibited by the metallic glass is not the total amount of icosahedral clusters,but the degree of global connectivity among them. 展开更多
关键词 metallic glass CRYSTALLIZATION molecular dynamics simulation local atomic clusters
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Atomic transport dynamics in crossed optical dipole trap
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作者 彭鹏 张正熙 +5 位作者 樊耀塬 殷国玲 毛德凯 陈徐宗 熊炜 周小计 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期293-301,共9页
We study the dynamical evolution of cold atoms in crossed optical dipole trap theoretically and experimentally. The atomic transport process is accompanied by two competitive kinds of physical mechanics, atomic loadin... We study the dynamical evolution of cold atoms in crossed optical dipole trap theoretically and experimentally. The atomic transport process is accompanied by two competitive kinds of physical mechanics, atomic loading and atomic loss.The loading process normally is negligible in the evaporative cooling experiment on the ground, while it is significant in preparation of ultra-cold atoms in the space station. Normally, the atomic loading process is much weaker than the atomic loss process, and the atomic number in the central region of the trap decreases monotonically, as reported in previous research. However, when the atomic loading process is comparable to the atomic loss process, the atomic number in the central region of the trap will initially increase to a maximum value and then slowly decrease, and we have observed the phenomenon first. The increase of atomic number in the central region of the trap shows the presence of the loading process, and this will be significant especially under microgravity conditions. We build a theoretical model to analyze the competitive relationship, which coincides with the experimental results well. Furthermore, we have also given the predicted evolutionary behaviors under different conditions. This research provides a solid foundation for further understanding of the atomic transport process in traps. The analysis of loading process is of significant importance for preparation of ultra-cold atoms in a crossed optical dipole trap under microgravity conditions. 展开更多
关键词 cold atom crossed optical dipole trap transport process
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The penetration depth of atomic radicals in tubes with catalytic surface properties
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作者 Domen PAUL Miran MOZETIC +3 位作者 Rok ZAPLOTNIK Alenka VESEL Gregor PRIMC Denis DONLAGIC 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第7期157-164,共8页
Catalysis of molecular radicals is often performed in interesting experimental configurations.One possible configuration is tubular geometry.The radicals are introduced into the tubes on one side,and stable molecules ... Catalysis of molecular radicals is often performed in interesting experimental configurations.One possible configuration is tubular geometry.The radicals are introduced into the tubes on one side,and stable molecules are exhausted on the other side.The penetration depth of radicals depends on numerous parameters,so it is not always feasible to calculate it.This article presents systematic measurements of the penetration depth of oxygen atoms along tubes made from nickel,cobalt,and copper.The source of O atoms was a surfatron-type microwave plasma.The initial density of O atoms depended on the gas flow and was 0.7×10^(21)m^(-3),2.4×10^(21)m^(-3),and 4.2×10^(21)m^(-3)at the flow rates of 50,300,and 600 sccm,and pressures of 10,35,and 60 Pa,respectively.The gas temperature remained at room temperature throughout the experiments.The dissociation fraction decreased exponentially along the length of the tubes in all cases.The penetration depths for well-oxidized nickel were 1.2,1.7,and 2.4 cm,respectively.For cobalt,they were slightly lower at 1.0,1.3,and 1.6 cm,respectively,while for copper,they were 1.1,1.3,and 1.7 cm,respectively.The results were explained by gas dynamics and heterogeneous surface association.These data are useful in any attempt to estimate the loss of molecular fragments along tubes,which serve as catalysts for the association of various radicals to stable molecules. 展开更多
关键词 oxygen plasma penetration depth CATALYSIS heterogeneous surface recombination atom loss
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Dependence of Rydberg-atom-based sensor performance on different Rydberg atom populations in one atomic-vapor cell
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作者 武博 姚佳伟 +2 位作者 吴逢川 安强 付云起 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期365-370,共6页
The atomic-vapor cell is a vital component for Rydberg atomic microwave sensors,and impacts on overall capability of Rydberg sensors.However,the conventional analysis approach on effect of vapor-cell length contains t... The atomic-vapor cell is a vital component for Rydberg atomic microwave sensors,and impacts on overall capability of Rydberg sensors.However,the conventional analysis approach on effect of vapor-cell length contains two implicit assumptions,that is,the same atomic population density and buffer gas pressure,which make it unable to accurately capture actual response about effect of Rydberg-atom-based sensor performance on different Rydberg atom populations.Here,utilizing a stepped cesium atomic-vapor cell with five different dimensions at the same atomic population density and buffer gas pressure,the height and full width at half maximum of electromagnetically induced transparency(EIT)signal,and the sensitivity of the atomic superheterodyne sensor are comprehensively investigated under conditions of the same Rabi frequencies(saturated laser power).It is identified that EIT signal height is proportional to the cell length,full width at half maximum and sensitivity grow with the increment of cell length to a certain extent.Employing the coherent integration signal theory and atomic linear expansion coefficient method,theoretical analysis of the EIT height and sensitivity are further investigated.The results could shed new light on understanding and design of ultrahigh-sensitivity Rydberg atomic microwave sensors and find promising applications in quantum measurement,communication,and imaging. 展开更多
关键词 Rydberg atom population Rydberg-atom-based receiver stepped atomic-vapor cell
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Atomically Dispersed Ruthenium Catalysts with Open Hollow Structure for Lithium-Oxygen Batteries
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作者 Xin Chen Yu Zhang +5 位作者 Chang Chen Huinan Li Yuran Lin Ke Yu Caiyun Nan Chen Chen 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第2期154-164,共11页
Lithium–oxygen battery with ultrahigh theoretical energy density is considered a highly competitive next-generation energy storage device,but its practical application is severely hindered by issues such as difficult... Lithium–oxygen battery with ultrahigh theoretical energy density is considered a highly competitive next-generation energy storage device,but its practical application is severely hindered by issues such as difficult decomposition of discharge products at present.Here,we have developed N-doped carbon anchored atomically dispersed Ru sites cathode catalyst with open hollow structure(h-RuNC)for Lithium–oxygen battery.On one hand,the abundance of atomically dispersed Ru sites can effectively catalyze the formation and decomposition of discharge products,thereby greatly enhancing the redox kinetics.On the other hand,the open hollow structure not only enhances the mass activity of atomically dispersed Ru sites but also improves the diffusion efficiency of catalytic molecules.Therefore,the excellent activity from atomically dispersed Ru sites and the enhanced diffusion from open hollow structure respectively improve the redox kinetics and cycling stability,ultimately achieving a high-performance lithium–oxygen battery. 展开更多
关键词 atomically dispersed Open hollow structure Discharge product LITHIUM Oxygen battery
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Atomically dispersed calcium as solid strong base catalyst with high activity and stability
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作者 Xiang-Bin Shao Zhi-Wei Xing +5 位作者 Si-Yu Liu Ke-Xin Miao Shi-Chao Qi Song-Song Peng Xiao-Qin Liu Lin-Bing Sun 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第10期1619-1626,共8页
Solid strong base catalysts are highly attractive for diverse reactions owing to their advantages of neglectable corrosion,facile separation,and environmental friendliness.However,their widespread applications are imp... Solid strong base catalysts are highly attractive for diverse reactions owing to their advantages of neglectable corrosion,facile separation,and environmental friendliness.However,their widespread applications are impeded by basic components aggregation and low stability.In this work,we fabricate single calcium atoms on graphene(denoted as Ca1/G)by use of a redox strategy for the first time,producing solid strong base catalyst with high activity and stability.The precursor Ca(NO_(3))_(2)is first reduced to CaO at 400℃ by the support graphene,forming CaO/G with conventional basic sites,and the subsequent reduction at 850℃results in the generation of Ca1/G with atomically dispersed Ca.Various characterizations reveal that Ca single atoms are anchored on graphene in tetra-coordination(Ca-C_(2)-N_(2))where N is in situ doped from Ca(NO_(3))_(2).The atomically dispersed Ca,along with their anchoring on the support,endow Ca1/G with high activity and stability toward the transesterification reaction of ethylene carbonate with methanol.The turnover frequency value reaches 128.0 h^(-1)on Ca1/G,which is much higher than the traditional counterpart CaO/G and various reported solid strong bases(2.9-46.2 h^(-1)).Moreover,the activity of Ca1/G is well maintained during 5 cycles,while 60%of activity is lost for the conventional analogue CaO/G due to the leaching of Ca. 展开更多
关键词 Solid strong base Single Ca atoms Heterogeneous catalysts TRANSESTERIFICATION REACTION
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Atomically Substitutional Engineering of Transition Metal Dichalcogenide Layers for Enhancing Tailored Properties and Superior Applications
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作者 Zhaosu Liu Si Yin Tee +1 位作者 Guijian Guan Ming‑Yong Han 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第5期248-284,共37页
Transition metal dichalcogenides(TMDs)are a promising class of layered materials in the post-graphene era,with extensive research attention due to their diverse alternative elements and fascinating semiconductor behav... Transition metal dichalcogenides(TMDs)are a promising class of layered materials in the post-graphene era,with extensive research attention due to their diverse alternative elements and fascinating semiconductor behavior.Binary MX2 layers with different metal and/or chalcogen elements have similar structural parameters but varied optoelectronic properties,providing opportunities for atomically substitutional engineering via partial alteration of metal or/and chalcogenide atoms to produce ternary or quaternary TMDs.The resulting multinary TMD layers still maintain structural integrity and homogeneity while achieving tunable(opto)electronic properties across a full range of composition with arbitrary ratios of introduced metal or chalcogen to original counterparts(0–100%).Atomic substitution in TMD layers offers new adjustable degrees of freedom for tailoring crystal phase,band alignment/structure,carrier density,and surface reactive activity,enabling novel and promising applications.This review comprehensively elaborates on atomically substitutional engineering in TMD layers,including theoretical foundations,synthetic strategies,tailored properties,and superior applications.The emerging type of ternary TMDs,Janus TMDs,is presented specifically to highlight their typical compounds,fabrication methods,and potential applications.Finally,opportunities and challenges for further development of multinary TMDs are envisioned to expedite the evolution of this pivotal field. 展开更多
关键词 Transition metal dichalcogenides atomic substitution Tailored structure Tunable bandgap Enhanced applications
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Improved Efficiency and Stability of Organic Solar Cells by Interface Modification Using Atomic Layer Deposition of Ultrathin Aluminum Oxide
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作者 Ai Lan Yiqun Li +8 位作者 Huiwen Zhu Jintao Zhu Hong Lu Hainam Do Yifan Lv Yonghua Chen Zhikuan Chen Fei Chen Wei Huang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第3期282-290,共9页
The interfacial contacts between the electron transporting layers(ETLs)and the photoactive layers are crucial to device performance and stability for OSCs with inverted architecture.Herein,atomic layer deposition(ALD)... The interfacial contacts between the electron transporting layers(ETLs)and the photoactive layers are crucial to device performance and stability for OSCs with inverted architecture.Herein,atomic layer deposition(ALD)fabricated ultrathin Al_(2)O_(3)layers are applied to modify the ETLs/active blends(PM6:BTP-BO-4F)interfaces of OSCs,thus improving device performance.The ALD-Al_(2)O_(3)thin layers on ZnO significantly improved its surface morphology,which led to the decreased work function of ZnO and reduced recombination losses in devices.The simultaneous increase in open-circuit voltage(V_(OC)),short-circuit current density(J_(SC))and fill factor(FF)were achieved for the OSCs incorporated with ALD-Al_(2)O_(3)interlayers of a certain thickness,which produced a maximum PCE of 16.61%.Moreover,the ALD-Al_(2)O_(3)interlayers had significantly enhanced device stability by suppressing degradation of the photoactive layers induced by the photocatalytic activity of ZnO and passivating surface defects of ZnO that may play the role of active sites for the adsorption of oxygen and moisture. 展开更多
关键词 atomic layer deposition interface modification organic solar cells STABILITY
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Optimal preparation of Bose and Fermi atomic gas mixtures of ^(87)Rb and ^(40)K in a crossed optical dipole trap
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作者 丁培波 单标 +5 位作者 赵宇航 杨雅婧 陈良超 孟增明 王鹏军 黄良辉 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期356-361,共6页
We report on the optimal production of the Bose and Fermi mixtures with ^(87) Rb and ^(40)K in a crossed optical dipole trap(ODT).We measure the atomic number and lifetime of the mixtures in combination of the spin st... We report on the optimal production of the Bose and Fermi mixtures with ^(87) Rb and ^(40)K in a crossed optical dipole trap(ODT).We measure the atomic number and lifetime of the mixtures in combination of the spin state |F=9/2,m_(F)=9/2> of^(40)K and |1,1>of ^(87) Rb in the ODT,which is larger and longer compared with the combination of the spin state |9/2,9/2> of^(40)K and 12,2) of ^(87)Rb in the ODT.We observe the atomic numbers of ^(87)Rb and ^(40)K shown in each stage of the sympathetic cooling process while gradually reducing the depth of the optical trap.By optimizing the relative loading time of atomic mixtures in the MOT,we obtain the large atomic number of ^(40)K(~6 ×10^(6)) or the mixtures of atoms with an equal number(~1.6 × 10^(6)) at the end of evaporative cooling in the ODT.We experimentally investigate the evaporative cooling in an enlarged volume of the ODT via adding a third laser beam to the crossed ODT and found that more atoms(8 × 10^(6)) and higher degeneracy(T/T_(F)=0.25) of Fermi gases are obtained.The ultracold atomic gas mixtures pave the way to explore phenomena such as few-body collisions and the Bose-Fermi Hubbard model,as well as for creating ground-state molecules of ^(87)Rb^(40)K. 展开更多
关键词 optical dipole trap Bose and Fermi gas mixtures atomic lifetime
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Implementation of sub-100 nm vertical channel-all-around(CAA) thin-film transistor using thermal atomic layer deposited IGZO channel
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作者 Yuting Chen Xinlv Duan +9 位作者 Xueli Ma Peng Yuan Zhengying Jiao Yongqing Shen Liguo Chai Qingjie Luan Jinjuan Xiang Di Geng Guilei Wang Chao Zhao 《Journal of Semiconductors》 EI CAS CSCD 2024年第7期40-44,共5页
In-Ga-Zn-O(IGZO) channel based thin-film transistors(TFT), which exhibit high on-off current ratio and relatively high mobility, has been widely researched due to its back end of line(BEOL)-compatible potential for th... In-Ga-Zn-O(IGZO) channel based thin-film transistors(TFT), which exhibit high on-off current ratio and relatively high mobility, has been widely researched due to its back end of line(BEOL)-compatible potential for the next generation dynamic random access memory(DRAM) application. In this work, thermal atomic layer deposition(TALD) indium gallium zinc oxide(IGZO) technology was explored. It was found that the atomic composition and the physical properties of the IGZO films can be modulated by changing the sub-cycles number during atomic layer deposition(ALD) process. In addition, thin-film transistors(TFTs) with vertical channel-all-around(CAA) structure were realized to explore the influence of different IGZO films as channel layers on the performance of transistors. Our research demonstrates that TALD is crucial for high density integration technology, and the proposed vertical IGZO CAA-TFT provides a feasible path to break through the technical problems for the continuous scale of electronic equipment. 展开更多
关键词 In-Ga-Zn-O(IGZO) thermal atomic layer deposition vertical channel thin-film transistor
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Performance optimization of a SERF atomic magnetometer based on flat-top light beam
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作者 袁子琪 唐钧剑 +1 位作者 林树东 翟跃阳 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期330-336,共7页
We explore the impact of pumping beams with different transverse intensity profiles on the performance of the spinexchange relaxation-free(SERF) atomic magnetometers(AMs). We conduct experiments comparing the traditio... We explore the impact of pumping beams with different transverse intensity profiles on the performance of the spinexchange relaxation-free(SERF) atomic magnetometers(AMs). We conduct experiments comparing the traditional Gaussian optically-pumped AM with that utilizing the flat-top optically-pumped(FTOP) method. Our findings reveal that the FTOP-based approach outperforms the conventional method, exhibiting a larger response, a narrower magnetic resonance linewidth, and a superior low-frequency noise performance. Specifically, the use of FTOP method leads to a 16% enhancement in average sensitivity within 1 Hz–30 Hz frequency range. Our research emphasizes the significance of achieving transverse polarization uniformity in AMs, providing insights for future optimization efforts and sensitivity improvements in miniaturized magnetometers. 展开更多
关键词 atomic magnetometer(AM) spin-exchange relaxation-free(SERF) flat-top light beam performance optimization
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