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Thin Film of Perovskite Oxide with Atomic Scale p-n Junctions 被引量:1
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作者 HU Bin HUANG Ke-ke +3 位作者 HOU Chang-min YUAN Hong-ming PANG Guang-sheng FENG Shou-hua 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第3期379-381,共3页
Thin films of perovskite manganese oxide Lao.66Ca0.29K0.05MnO3(LCKMO) on Au/ITO(ITO=indium tin oxide) substrates were prepared by off-axis radio frequency magnetron sputtering and characterized by X-ray diffrac- t... Thin films of perovskite manganese oxide Lao.66Ca0.29K0.05MnO3(LCKMO) on Au/ITO(ITO=indium tin oxide) substrates were prepared by off-axis radio frequency magnetron sputtering and characterized by X-ray diffrac- tion(XRD), high-resolution transmission electron microscopy(HRTEM), and conductive atomic force microscopy (C-AFM) at room temperature. The thin films with thickness ranged from 100 nm to 300 nm basically show cubic structures with a=0.3886 nm, the same as that of the raw material used, but the structures are highly modulated. C-AFM results revealed that the atomic scale p-n junction feature of the thin films was the same as that of the single crystals. The preparation of the thin films thus further confirms the possibility of their application extending from micrometer-sized single crystals to macroscopic thin film. 展开更多
关键词 Perovskite oxide Thin film Atomic scale p-n junction
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Systematic review of mitochondrial dysfunction and oxidative stress in aging:A focus on neuromuscular junctions
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作者 Senlin Chai Ning Zhang +8 位作者 Can Cui Zhengyuan Bao Qianjin Wang Wujian Lin Ronald Man Yeung Wong Sheung Wai Law Rebecca Schönmehl Christoph Brochhausen Wing Hoi Cheung 《Neural Regeneration Research》 2026年第5期1947-1960,共14页
Mitochondrial dysfunction and oxidative stress are widely regarded as primary drivers of aging and are associated with several neurodegenerative diseases.The degeneration of motor neurons during aging is a critical pa... Mitochondrial dysfunction and oxidative stress are widely regarded as primary drivers of aging and are associated with several neurodegenerative diseases.The degeneration of motor neurons during aging is a critical pathological factor contributing to the progression of sarcopenia.However,the morphological and functional changes in mitochondria and their interplay in the degeneration of the neuromuscular junction during aging remain poorly understood.A defined systematic search of the Pub Med,Web of Science and Embase databases(last accessed on October 30,2024)was conducted with search terms including'mitochondria','aging'and'NMJ'.Clinical and preclinical studies of mitochondrial dysfunction and neuromuscular junction degeneration during aging.Twentyseven studies were included in this systematic review.This systematic review provides a summary of morphological,functional and biological changes in neuromuscular junction,mitochondrial morphology,biosynthesis,respiratory chain function,and mitophagy during aging.We focus on the interactions and mechanisms underlying the relationship between mitochondria and neuromuscular junctions during aging.Aging is characterized by significant reductions in mitochondrial fusion/fission cycles,biosynthesis,and mitochondrial quality control,which may lead to neuromuscular junction dysfunction,denervation and poor physical performance.Motor nerve terminals that exhibit redox sensitivity are among the first to exhibit abnormalities,ultimately leading to an early decline in muscle strength through impaired neuromuscular junction transmission function.Parg coactivator 1 alpha is a crucial molecule that regulates mitochondrial biogenesis and modulates various pathways,including the mitochondrial respiratory chain,energy deficiency,oxidative stress,and inflammation.Mitochondrial dysfunction is correlated with neuromuscular junction denervation and acetylcholine receptor fragmentation,resulting in muscle atrophy and a decrease in strength during aging.Physical therapy,pharmacotherapy,and gene therapy can alleviate the structural degeneration and functional deterioration of neuromuscular junction by restoring mitochondrial function.Therefore,mitochondria are considered potential targets for preserving neuromuscular junction morphology and function during aging to treat sarcopenia. 展开更多
关键词 AGING mitochondrial dysfunction neuromuscular junction oxidative stress SARCOPENIA systematic review
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Conformational bifurcation drives dual transport regimes in molecular junctions:Unsupervised machine learning insights
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作者 Yuhong Chen Ioan Bâldea +1 位作者 Elad Koren Zuoti Xie 《Smart Molecules》 2026年第1期154-164,共11页
Control over charge transport in molecular–scale devices requires a deep understanding of how minute structural changes influence electronic properties.Here,we demonstrate dual transport regimes in tunnel junctions o... Control over charge transport in molecular–scale devices requires a deep understanding of how minute structural changes influence electronic properties.Here,we demonstrate dual transport regimes in tunnel junctions of n-alk-1-yne(CnA)molecules with gold electrodes driven by conformational bifurcation—the emergence of two nearly isoenergetic(planar and skewed)molecular conformers(dihedral anglesα=180°andα≈65°at the alkyne terminus in the gas phase).Although the energy differences are small,these subtle conformational differences manifest as distinct transport behaviors,uncovered through unsupervised machine learning,which identified two junction groups:“short”and“long”chains,with distinct attenuation factors(β_(short)≈1.0 vs.β_(long)≈0.74)and contact conductances(G_(c,short)≈200μS vs.G_(c,long)≈8μS).This dramatic impact of the dihedral angle exceeds the impact of the inter-ring twist angle in biphenyl-based junctions and rivals changes induced by switching from gold to platinum electrodes or from monothiol to dithiol anchors in oligoacene and oligophenylene junctions.X-ray photoelectron spectroscopy(XPS)confirmed this bifurcation,linking the“short”and“long”groups to planar and skewed conformers,with dihedrals remarkably agreeing with the gas-phase values.This work establishes conformational bifurcation as a promising route for designing programmable nanotransport properties through anchor-group control. 展开更多
关键词 charge transport conformational bifurcation molecular electronics molecular junctions n-alk-1-ynes structure-property relationships
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Two-dimensional organic single-crystalline p-n junctions for ambipolar field transistors 被引量:1
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作者 Lu Wang Cong Wang +3 位作者 Xixia Yu Lei Zheng Xiaotao Zhang Wenping Hu 《Science China Materials》 SCIE EI CSCD 2020年第1期122-127,共6页
Two-dimensional single-crystalline p-n junctions of organic semiconductors(pn-2 DCOSs) show great potential in organic logic circuits due to their single crystal nature and excellent ambipolar charge transport. Howeve... Two-dimensional single-crystalline p-n junctions of organic semiconductors(pn-2 DCOSs) show great potential in organic logic circuits due to their single crystal nature and excellent ambipolar charge transport. However,there are only few reports on pn-2 DCOSs because it is difficult to obtain such highly ordered structure in p-n junction.Herein, a novel and effective solution processing method of secondary transfer technology based on the facile drop casting is used to fabricate devices of pn-2 DCOSs based on C8-BTBT(p-type) and TFT-CN(n-type) successfully. The high-performance ambipolar field transistors based on such ultrathin pn-2 DCOSs with several molecular layers thickness show wellbalanced ambipolar charge transport behaviors with hole mobility as high as 0.43 cm^2 V^-1 s^-1 and electron mobility up to 0.11 cm^2 V^-1 s(^-1), respectively. This work is essential for studying the intrinsic properties of organic p-n junctions and achieving high performance in organic complementary circuits. 展开更多
关键词 two-dimensional materials ambipolar field transistors p-n junctions single crystals
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Wafer-scale arrayed p-n junctions based on few-layer epitaxial GaTe 被引量:5
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作者 Xiang Yuan Lei Tang +12 位作者 Peng Wang Zhigang Chen Yichao Zou Xiaofeng Su Cheng Zhang Yanwen Liu Weiyi Wang Cong Liu Fansheng Chen Jin Zou Peng Zhou Weida Hu Faxian Xiu 《Nano Research》 SCIE EI CAS CSCD 2015年第10期3332-3341,共10页
Two-dimensional (2D) materials have attracted substantial attention in electronic and optoelectronic applications with the superior advantages of being flexible, transparent, and highly tunable. Gapless graphene exh... Two-dimensional (2D) materials have attracted substantial attention in electronic and optoelectronic applications with the superior advantages of being flexible, transparent, and highly tunable. Gapless graphene exhibits ultra-broadband and fast photoresponse while the 2D semiconducting MoS2 and GaTe exhibit high sensitivity and tunable responsivity to visible light. However, the device yield and repeatability call for further improvement to achieve large-scale uniformity. Here, we report a layer-by-layer growth of wafer-scale GaTe with a high hole mobility of 28.4 cm^2/(V.s) by molecular beam epitaxy. The arrayed p-n )unctions were developed by growing few-layer GaTe directly on fhree-inch Si wafers. The resultant diodes reveal good rectifying characteristics and a high photovoltaic external quantum efficiency up to 62% at 4.8 μW under zero bias. The photocurrent reaches saturation fast enough to capture a time constant of 22 μs and shows no sign of device degradation after 1.37 million cycles of operation. Most strikingly, such high performance has been achieved across the entire wafer, making the volume production of devices accessible. Finally, several photoimages were acquired by the GaTe/Si photodiodes with reasonable contrast and spatial resolution, demonstrating the potential of integrating the 2D materials with silicon technology for novel optoelectronic devices. 展开更多
关键词 GATE wafer-scaletwo-dimensional materials p-n junction imaging PHOTODIODE PHOTOSENSOR
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Tactile tribotronic reconfigurable p-n junctions for artificial synapses 被引量:6
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作者 Mengmeng Jia Pengwen Guo +4 位作者 Wei Wang Aifang Yu Yufei Zhang Zhong Lin Wang Junyi Zhai 《Science Bulletin》 SCIE EI CSCD 2022年第8期803-812,M0003,共11页
The emulation of biological synapses with learning and memory functions and versatile plasticity is significantly promising for neuromorphic computing systems.Here,a robust and continuously adjustable mechanoplastic s... The emulation of biological synapses with learning and memory functions and versatile plasticity is significantly promising for neuromorphic computing systems.Here,a robust and continuously adjustable mechanoplastic semifloating-gate transistor is demonstrated based on an integrated graphene/hexagonal boron nitride/tungsten diselenide van der Waals heterostructure and a triboelectric nanogenerator(TENG).The working states(p-n junction or n;-n junction)can be manipulated and switched under the sophisticated modulation of triboelectric potential derived from mechanical actions,which is attributed to carriers trapping and detrapping in the graphene layer.Furthermore,a reconfigurable artificial synapse is constructed based on such mechanoplastic transistor that can simulate typical synaptic plasticity and implement dynamic control correlations in each response mode by further designing the amplitude and duration.The artificial synapse can work with ultra-low energy consumption at 74.2 f J per synaptic event and the extended synaptic weights.Under the synergetic effect of the semifloating gate,the synaptic device can enable successive mechanical facilitation/depression,short-/long-term plasticity and learning-experience behavior,exhibiting the mechanical behavior derived synaptic plasticity.Such reconfigurable and mechanoplastic features provide an insight into the applications of energyefficient and real-time interactive neuromodulation in the future artificial intelligent system beyond von Neumann architecture. 展开更多
关键词 Reconfigurable p-n junction Semifloating-gate transistor Triboelectric potential Artificial synapses Synaptic plasticity
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P-N阻燃剂对低密度纤维板热烟释放性能的影响机制
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作者 康地 张世琰 +2 位作者 李志高 袁利萍 范友华 《建筑材料学报》 北大核心 2026年第3期347-355,共9页
为了提升纤维板的阻燃性能,以氨基三亚甲基膦酸(ATMP)、1,3,5-三(2-羟乙基)氰尿酸(THEIC)和三聚氰胺(MEL)为原料,合成了一种新型P-N阻燃剂1,3,5-三(2-羟乙基-氨基(亚甲基膦酸酯-二-亚甲基磷酸三聚氰胺盐))氰尿酸(TAM),并将其与竹纤维复... 为了提升纤维板的阻燃性能,以氨基三亚甲基膦酸(ATMP)、1,3,5-三(2-羟乙基)氰尿酸(THEIC)和三聚氰胺(MEL)为原料,合成了一种新型P-N阻燃剂1,3,5-三(2-羟乙基-氨基(亚甲基膦酸酯-二-亚甲基磷酸三聚氰胺盐))氰尿酸(TAM),并将其与竹纤维复合,通过热压工艺制备出阻燃低密度纤维板(LDF)。对TAM的化学结构进行了表征,并探讨了其添加量对LDF热解行为和阻燃性能的影响规律。结果表明:新型P-N阻燃剂TAM已成功合成,所制备的LDF具有良好阻燃性能;对比对照试样,当TAM添加量为15%时,LDF的极限氧指数达35.7%,峰值热释放速率(PHRR)降低了20.15%,总烟生成量TSP降低了84.70%,残炭率增加了66.25%;TAM在燃烧过程中通过气相稀释、自由基捕获和酸催化成炭机制,赋予纤维板优异的阻燃性能。 展开更多
关键词 纤维板 p-n阻燃剂 阻燃性能 阻燃机理
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Performance Control and Application of ZnO-Based P-N Junction Piezoelectric Devices
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作者 Xudong Shen Dongying Liu Li Zhao 《Journal of Electronic Research and Application》 2025年第1期81-87,共7页
Zinc oxide(ZnO),as a broadband gap semiconductor material,exhibits unique physical and chemical properties that make it highly suitable for optoelectronics,piezoelectric devices,and gas-sensitive sensors,showing signi... Zinc oxide(ZnO),as a broadband gap semiconductor material,exhibits unique physical and chemical properties that make it highly suitable for optoelectronics,piezoelectric devices,and gas-sensitive sensors,showing significant potential for various applications.This paper focuses on the regulation and application of ZnO-based p-n junctions and piezoelectric devices.It discusses in detail the preparation of ZnO materials,the construction of p-n junctions,the optimization of piezoelectric device performance,and its application in various fields.By employing different preparation methods and strategies,high-quality ZnO thin films can be grown,and effective control of p-type conductivity achieved.This study provides both a theoretical foundation and technical support for controlling the performance of ZnO-based piezoelectric devices,as well as paving new pathways for the broader application of ZnO materials. 展开更多
关键词 ZNO p-n junction Piezoelectric device Performance control APPLICATION
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N-dopedβ-Ga_(2)O_(3)/Si-dopedβ-Ga_(2)O_(3) linearly-graded p-n junction by a one-step integrated approach
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作者 Chenxing Liu Zhengyuan Wu +6 位作者 Hongchao Zhai Jason Hoo Shiping Guo Jing Wan Junyong Kang Junhao Chu Zhilai Fang 《Journal of Materials Science & Technology》 2025年第6期196-206,共11页
The p-n junction is the foundation building structure for manufacturing various electronic and optoelec-tronic devices.Ultrawide bandgap semiconductors are expected to overcome the limited power capability of Si-based... The p-n junction is the foundation building structure for manufacturing various electronic and optoelec-tronic devices.Ultrawide bandgap semiconductors are expected to overcome the limited power capability of Si-based electronic device,however,it is very difficult to achieve efficient bipolar doping due to the asymmetric doping effect,thereby impeding the development of p-n homojunction and related bipolar devices,especially for the Ga_(2)O_(3)-based materials and devices.Here,we demonstrate a unique one-step integrated growth of p-type N-doped(201)β-Ga_(2)O_(3)/n-type Si-doped(¯201)β-Ga_(2)O_(3)films by phase tran-sition and in-situ pre-doping of dopants,and fabrication of fullβ-Ga_(2)O_(3)linearly-graded p-n homojunc-tion diode from them.The fullβ-Ga_(2)O_(3)p-n homojunction diode possesses a large built-in potential of 4.52 eV,a high operation electric field>2.90 MV/cm in the reverse-bias regime,good longtime-stable rectifying behaviors with a rectification ratio of 104,and a high-speed switching and good surge robust-ness with a weak minority-carrier charge storage.Our work opens the way to the fabrication of Ga_(2)O_(3)-based p-n homojunction,lays the foundation for fullβ-Ga_(2)O_(3)-based bipolar devices,and paves the way for the novel fabrication of p-n homojunction for wide-bandgap oxides. 展开更多
关键词 β-Ga_(2)O_(3)films in-situ pre-doping Linearly-graded p-n junction Forward and reverse characteristics Built-in potential
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Photo-enhanced Co single-atom catalyst with a staggered p-n heterojunction:unraveling its high oxygen catalytic performance in zinc-air batteries and fuel cells 被引量:1
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作者 Zhaodi Wang Yang Zhang +8 位作者 Junxuan Zhang Nengneng Xu Tuo Lu Biyan Zhuang Guicheng Liu Woochul Yang Hao Lei Binglun Tian Jinli Qiao 《Chinese Journal of Catalysis》 2025年第6期311-321,共11页
The sluggish kinetics of the oxygen reduction reaction(ORR)and high over potential of oxygen evolution reaction(OER)are big challenges in the development of high-performance zinc-air batteries(ZABs)and fuel cells.In t... The sluggish kinetics of the oxygen reduction reaction(ORR)and high over potential of oxygen evolution reaction(OER)are big challenges in the development of high-performance zinc-air batteries(ZABs)and fuel cells.In this work,we report a rational design and a simple fabrication strategy of a photo-enhanced Co single-atom catalyst(SAC)comprising g-C3N4 coupled with cobalt-nitrogen-doped hierarchical mesoporous carbon(Co-N/MPC),forming a staggered p-n heterojunction that effectively improves charge separation and enhances electrocatalytic activity.The incorporation of Co SACs and g-C3N4 synergistically optimizes the photogenerated electron-hole pair separation,significantly boosting the intrinsic ORR-OER duplex activity.Under illumination,g-C_(3)N_(4)@Co-N/MPC exhibits an outstanding ORR half-wave potential(E1/2)of 0.841 V(vs.RHE)in 0.1 mol L^(–1)KOH and a low OER overpotential of 497.4 mV(vs.RHE)at 10 mA cm^(–2)in 1 mol L^(–1)KOH.Notably,the catalyst achieves an exceptional peak power density of 850.7 mW cm^(–2)in ZABs and of 411 mW cm^(–2)even in H_(2)-air fuel cell.In addition,g-C_(3)N_(4)@Co-N/MPC-based ZABs also show remarkable cycling stability exceeding 250 h.The advanced photo-induced charge separation at the p-n heterojunction facilitates faster electron transfer kinetics,and the mass transport owing to hierarchical mesoporous structure of Co-N-C,thereby reducing the overpotential and enhancing the overall energy conversion efficiency.This work provides a new perspective on designing next-generation of single-atom dispersed oxygen reaction catalysts,paving the way for high-performance photo-enhanced energy storage and conversion systems. 展开更多
关键词 Co single-atom Hierarchical mesoporous carbon Photo-enhancement p-n Heterojunction Oxygen catalytic reaction
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Achieving Large Six Non-Volatile States via Monolayer Homologous Multiferroic MoPtGe_(2)S_(6)in van der Waals Tunnel Junctions 被引量:1
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作者 Ruixia Yang Xujin Zhang +3 位作者 Jianhua Xiao Zhi Yan Fang Wang Xiaohong Xu 《Chinese Physics Letters》 2025年第7期251-262,共12页
Multiferroic tunnel junctions(MFTJs),which combine tunneling magnetoresistance(TMR)and electroresistance(TER)efects,have emerged as key candidates for data storage.Two-dimensional van der Waals(vdW)MFTJs,in particular... Multiferroic tunnel junctions(MFTJs),which combine tunneling magnetoresistance(TMR)and electroresistance(TER)efects,have emerged as key candidates for data storage.Two-dimensional van der Waals(vdW)MFTJs,in particular,are promising spintronic devices for the post-Moore era.However,these vdW MFTJs are typically based on multiferroics composed of ferromagnetic and ferroelectric materials or multilayer magnetic materials with sliding ferroelectricity,which increases device fabrication complexity.In this work,we design a vdW MFTJ using bilayer MoPtGe_(2)S_(6),a material with homologous multiferroicity in each monolayer,combined with symmetric PtTe_(2)electrodes.Using frst-principles calculations based on density functional theory and nonequilibrium Green's functions,we theoretically explore the spin-polarized electronic transport properties of this MFTJ.By controlling the ferroelectric and ferromagnetic polarization directions of bilayer MoPtGe_(2)S_(6),the MFTJ can exhibit six distinct non-volatile resistance states,with maximum TMR(137%)and TER(1943%)ratios.Under biaxial strain,TMR and TER can increase to 265%and 4210%,respectively.The TER ratio also increases to 2186%under a 0.1 V bias voltage.Remarkably,the MFTJ exhibits a pronounced spin-fltering and a signifcant negative diferential resistance efect.These fndings not only highlight the potential of monolayer multiferroic MoPtGe_(2)S_(6)for MFTJs but also ofer valuable theoretical insights for future experimental investigations. 展开更多
关键词 multiferroic tunnel junctions mftjs which multiferroic tunnel junctions data storagetwo dimensional tunneling magnetoresistance tmr multilayer magnetic materials sliding ferroelectricitywhich spintronic devices monolayer moptge s
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Mode-conversion-based silicon photonic modulator loaded by a combination of lateral and interleaved p-n junctions 被引量:1
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作者 Omid Jafari Sasan Zhalehpour +1 位作者 Wei Shi and Sophie LaRochelle 《Photonics Research》 SCIE EI CAS CSCD 2021年第4期471-476,共6页
We experimentally demonstrate a silicon photonic modulator that can be loaded with a combination of lateral and interleaved p-n junctions to enhance its phase modulation.We use an asymmetric Bragg grating to introduce... We experimentally demonstrate a silicon photonic modulator that can be loaded with a combination of lateral and interleaved p-n junctions to enhance its phase modulation.We use an asymmetric Bragg grating to introduce mode conversion in the active area,allowing the modulator to operate in reflection without introducing additional on-chip loss.With a compact footprint(phase shifter length of 290μm),the modulator demonstrates a modulation speed up to 45 Gb/s with a bit error rate below the 7% forward-error-correction(FEC)threshold(up to 55 Gb/s with 20% FEC),and a low power consumption of 226 fJ/bit. 展开更多
关键词 Gb/s MODULATOR junctions
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氮掺杂石墨烯量子点-NaBiO_(3)/BiOCl p-n异质结光催化剂的制备及可见光催化降解罗丹明B的性能研究
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作者 王津津 伍素云 +3 位作者 刘水林 刘宁 孙爱明 唐新德 《环境科学学报》 北大核心 2026年第2期146-157,共12页
在环境光催化中,提高光生载流子分离效率从而提高光催化性能仍然具有挑战性.本研究通过简单的离子蚀刻和原位沉积方法开发了N掺杂石墨烯量子点(NGQDs)-NaBiO_(3)/BiOCl(NNBC)p-n异质结光催化剂,其在光生电子/空穴对的分离方面表现出优... 在环境光催化中,提高光生载流子分离效率从而提高光催化性能仍然具有挑战性.本研究通过简单的离子蚀刻和原位沉积方法开发了N掺杂石墨烯量子点(NGQDs)-NaBiO_(3)/BiOCl(NNBC)p-n异质结光催化剂,其在光生电子/空穴对的分离方面表现出优异的性能,并对罗丹明B(RhB)显示出显著增强的可见光降解活性,这主要归因于NaBiO_(3)和BiOCl形成的p-n异质结以及NGQDs的强电子转移/存储能力.在NNBC可见光降解RhB的过程中,超氧化自由基和光生空穴为主要活性物种,线性氧是次要活性物种.此外,NNBC复合材料优异的光催化活性和高光稳定性使得其在污染物降解方面具有广阔的应用潜力.本研究为提高商品化的NaBiO_(3)·2H_(2)O在环境应用中的光催化效率提供了一种新的策略. 展开更多
关键词 NGQDs-NaBiO_(3)/BiOCl(NNBC) p-n异质结光催化剂 罗丹明B(RhB) 光催化降解机理 可见光
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Colossal magnetoresistive p-n junctions of perovskite oxide La_(0.9)Sr_(0.1)MnO_3/SrNb_(0.01)Ti_(0.99)O_3 被引量:2
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作者 L Huibin, DAI Souyu, CHEN Zhenghao, YAN Lei, ZHOU Yueliang & YANG Guozhen Laboratory of Optical Physics, Institute of Physics & Center for Condensed Matter Physics, Chinese Academy of Sciences, 100080 Beijing, China 《Chinese Science Bulletin》 SCIE EI CAS 2003年第13期1328-1330,共3页
We have successfully fabricated the colossal magnetoresistive (CMR) p-n junctions of perovskite oxide La0.9Sr0.1MnO3/SrNb0.01Ti0.99O3 (LSMO/SNTO) with laser molecular beam epitaxy. The I-V characteristics of the LSMO/... We have successfully fabricated the colossal magnetoresistive (CMR) p-n junctions of perovskite oxide La0.9Sr0.1MnO3/SrNb0.01Ti0.99O3 (LSMO/SNTO) with laser molecular beam epitaxy. The I-V characteristics of the LSMO/SNTO p-n junctions as a function of applied magnetic field (05 T) were studied between 100 and 300 K. We found that the p-n junction exhibited the CMR behavior. The CMR ratio rR/R0 (rR = RH - R0) is positive in magnetic fields below 0.13 T and at high temperature, while it displays a negative CMR near 100 K and in magnetic fields over 0.13 T. The CMR ratio values are 8% at 0.1 T and 13% at 5 T and 300 K, 40% at 0.1 T and 150 K, 10% at 0.13 T and 60% at 5 T and 100 K. The CMR behavior of the p-n junction is different from those of the LaMnO3 compound family. 展开更多
关键词 巨磁电阻 钙钛矿氧化物 LSMO/SNTO CMR 激光分子束外延 超导体
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Effect of side group on mechanically induced conductance switching in 4,40-dipyridyl-based single-molecule junctions
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作者 Zhen Wan Chang-Feng Zheng +5 位作者 Lin Liu Yun-Long Ge Guang-Ping Zhang Shuai Qiu Hui Wang Zong-Liang Li 《Chinese Physics B》 2025年第8期678-684,共7页
The forming processes of 4,40-dipyridyl-based single-molecule junctions and mechanically induced conductance switching as well as the side-group effects are systematically investigated by applying the ab initio-based ... The forming processes of 4,40-dipyridyl-based single-molecule junctions and mechanically induced conductance switching as well as the side-group effects are systematically investigated by applying the ab initio-based adiabatic geometric optimization method and the one-dimensional transmission combined with three-dimensional correction approximation(OTCTCA)method.The numerical results show that for the 4,40-dipyridyl with a p-conjugated phenyl-phosphoryl or diphenylsilyl side group,the pyridyl vertically anchors on the second atomic layer of the pyramid-shaped Au tip electrode at small inter-electrode distances by laterally pushing the apical Au atom aside,which induces stronger pyridyl-electrode coupling and high-conductance state of the formed junctions.As the inter-electrode distance increases,the pyridyl shifts to the apical Au atom of the tip electrode.This apical Au atom introduces additional scatterings to the tunneling electrons and significantly decreases the conductance of the junctions.Furthermore,for the 4,40-dipyridyl with a phenyl-phosphoryl side group,the probability of manifesting the high-conductance state is decreased due to the oxygen atom reducing the probability of the pyridyl adsorbing on the second layer of Au tip electrode.In contrast,for the 4,40-dipyridyl with a nonconjugated cyclohexyl-phosphoryl side group,the steric hindrance from the bulky cyclohexyl group leads the molecule to preferentially form the O-Au contact,which prevents both the high conductance and mechanically induced conductance switching of the junction.Our results provide a theoretical understanding of the side-group effects on electronic transport properties of single-molecule junctions,offering an alternative explanation for the experimental observations. 展开更多
关键词 single-molecule junction electron transport properties conductance switching side-group effects
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Plasmonic tandem heterojunctions enable high-efficiency charge transfer for broad spectrum photocatalytic hydrogen production
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作者 Wenxuan Chen Xiu-Qing Qiao +6 位作者 Guo Hui Bojing Sun Dongfang Hou Meidi Wang Xueqian Wu Tao Wu Dong-Sheng Li 《Journal of Energy Chemistry》 2025年第1期710-720,共11页
Rational engineering of semiconductor photocatalysts for efficient hydrogen production is of great significance but still challenging,primarily due to the limitations in charge transfer kinetics.Herein,a fascinating p... Rational engineering of semiconductor photocatalysts for efficient hydrogen production is of great significance but still challenging,primarily due to the limitations in charge transfer kinetics.Herein,a fascinating plasmonic tandem heterojunction with the hc-CdS/Mo_(2)C@C heterostructure is aimfully prepared for effectively promoting the charge separation kinetics of the CdS photocatalyst via the synergistic strategy of phase junction,Schottky junction,and photothermal effect.The difference in atomic configuration between cubic-CdS (c-CdS) and hexagonal-CdS (h-CdS) leads to effective charge separation through a typical Ⅱ charge transfer mechanism,and plasmonic Schottky junction further extracts the electrons in the hc-CdS phase junction to realize gradient charge transfer.Besides,the photothermal effect of Mo_(2)C@C helps to expand the light absorption,accelerate charge transfer kinetics,and reduce the hydrogen evolution energy barrier.The carbon layer provides a fast channel for charge transfer and protects the photocatalyst from photocorrosion.As a result,the optimized hc-CMC photocatalyst exhibits a significantly high photocatalytic H_(2)production activity of 28.63 mmol/g/h and apparent quantum efficiency of 61.8%,surpassing most of the reported photocatalysts.This study provides a feasible strategy to enhance the charge transfer kinetics and photocatalytic activity of CdS by constructing plasmonic tandem heterogeneous junctions. 展开更多
关键词 HETEROjunctions Mo_(2)C LSPR PHOTOCATALYST Phase junction Schottkyjunction Photothermal effect
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Design of shortcuts to adiabaticity for Bose-Einstein condensate dynamics in soliton Josephson junctions
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作者 Jingru Wu Chengyu Han Qian Kong 《Communications in Theoretical Physics》 2025年第3期130-139,共10页
This article primarily establishes a two-soliton system and employs the Lewis-Riesenfeld invariant inverse control method to achieve shortcuts to adiabaticity(STA)technology.We study an atomic soliton Josephson juncti... This article primarily establishes a two-soliton system and employs the Lewis-Riesenfeld invariant inverse control method to achieve shortcuts to adiabaticity(STA)technology.We study an atomic soliton Josephson junctions(SJJs)device and subsequently compare and analyze it with atomic bosonic Josephson junctions.Moreover,we use higher-order expressions of the auxiliary equations to optimize the results and weaken the detrimental effect of the sloshing amplitude.We find that in the adiabatic shortcut evolution of two systems with time-containing tunnelling rates,the SJJs system is more robust over a rather short time evolution.In comparison with linear ramping,the STA technique is easier to achieve with the precise modulation of the quantum state in the SJJs system. 展开更多
关键词 soliton josephson junctions shortcuts to adiabaticity double-well potential inverse engineering amplitude shaking
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Optimization of Skyrmionic Magnetic Tunnel Junctions
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作者 Mengqi Zhao Aitian Chen +5 位作者 Enlong Liu Le Zhao Shasha Wang Shikun He Xixiang Zhang Wanjun Jiang 《Chinese Physics Letters》 2025年第4期153-165,共13页
Magnetic skyrmions are recognized as potential information carriers for building the next-generation spintronic memory and logic devices.Towards functional device applications,efficient electrical detection of skyrmio... Magnetic skyrmions are recognized as potential information carriers for building the next-generation spintronic memory and logic devices.Towards functional device applications,efficient electrical detection of skyrmions at room temperature is one of the most important prerequisites. 展开更多
关键词 skyrmionic magnetic tunnel junctions spintronic memory information carriers OPTIMIZATION electrical detection skyrmions functional device magnetic skyrmions
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TiO_(2)Electron Transport Layer with p-n Homojunctions for Efficient and Stable Perovskite Solar Cells
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作者 Wenhao Zhao Pengfei Guo +8 位作者 Jiahao Wu Deyou Lin Ning Jia Zhiyu Fang Chong Liu Qian Ye Jijun Zou Yuanyuan Zhou Hongqiang Wang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第10期1-14,共14页
Low-temperature processed electron transport layer(ETL)of TiO_(2)that is widely used in planar perovskite solar cells(PSCs)has inherent low carrier mobility,resulting in insufficient photogenerated elec-tron transport... Low-temperature processed electron transport layer(ETL)of TiO_(2)that is widely used in planar perovskite solar cells(PSCs)has inherent low carrier mobility,resulting in insufficient photogenerated elec-tron transport and thus recombination loss at buried interface.Herein,we demonstrate an effective strategy of laser embedding of p-n homojunctions in the TiO_(2)ETL to accelerate electron transport in PSCs,through localized build-in electric fields that enables boosted electron mobility by two orders of magnitude.Such embedding is found significantly helpful for not only the enhanced crystallization quality of TiO_(2)ETL,but the fabrication of perovskite films with larger-grain and the less-trap-states.The embedded p-n homojunction enables also the modulation of interfacial energy level between perovskite layers and ETLs,favoring for the reduced voltage deficit of PSCs.Benefiting from these merits,the formamidinium lead iodide(FAPbI_(3))PSCs employing such ETLs deliver a champion efficiency of 25.50%,along with much-improved device stability under harsh conditions,i.e.,maintain over 95%of their initial efficiency after operation at maximum power point under continuous heat and illumination for 500 h,as well as mixed-cation PSCs with a champion efficiency of 22.02%and over 3000 h of ambient storage under humidity stability of 40%.Present study offers new possibilities of regulating charge transport layers via p-n homojunction embedding for high performance optoelectronics. 展开更多
关键词 Electron transport layer p-n homojunction Electron mobility Buried interface Perovskite solar cells
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Interfacial design and thermoelectric properties of C_(3)N_(4)-C_(20) molecular junctions based on quantum interference
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作者 Shutao Hu Meng Qian +1 位作者 Gang Zhang Bei Zhang 《Chinese Physics B》 2025年第6期109-115,共7页
Quantum interference effect serves as a critical strategy for addressing incorrect energy level alignment between frontier molecular orbitals and electrodes in molecular junctions. Weak-coupling structures offer an ef... Quantum interference effect serves as a critical strategy for addressing incorrect energy level alignment between frontier molecular orbitals and electrodes in molecular junctions. Weak-coupling structures offer an effective approach to suppress phonon thermal conductance. The thermoelectric properties of pure C_(3)N_(4) nanoribbon devices and C_(3)N_(4)-C_(20) molecular junctions are systematically investigated based on density functional theory(DFT) combined with nonequilibrium Green's function(NEGF) formalism. The results show that pure C_(3)N_(4) nanoribbon devices have superior charge transport capabilities and excellent Seebeck coefficients. A remarkable thermoelectric figure of merit(ZT = 0.98)is achieved near 0.09 e V. The pronounced scattering effect induced by embedding a C_(20) molecule in the center of the C_(3)N_(4) nanoribbon significantly suppresses phonon transport. A maximum ZT value of 1.68 is observed at 0.987 e V. The electron mobility of C_(3)N_(4)-C_(20)-par is effectively increased due to quantum interference effect which greatly improves the alignment between the C_(20) molecule's frontier orbital energy level and C_(3)N_(4) electrodes. The C_(3)N_(4)-C_(20)-van der Waals(vd W) molecular junction allows very few phonons to pass through the C_(20) molecule from the left electrode to the right electrode. As a result, the C_(3)N_(4)-C_(20)-vd W junction achieves an excellent ZT value of 3.82 near the Femi level. 展开更多
关键词 quantum interference effect C_(3)N_(4)-C_(20)molecular junctions thermoelectric properties first-principles theory
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