Small
·
2021
·Vol. 18
·期 5
·2104460
·
IF 13.281
Yanan Huang,Jianguo Si,Shuai Lin,Hongyan Lv,Wenhai Song,Ranran Zhang,Xuan Luo,Wenjian Lu,Xuebin Zhu,Yuping Sun
3D anisotropic functional properties (such as magnetic, electrical, thermal, and optical properties, etc.) in a single material are not only beneficial to the multipurpose of a material, but also helpful to enrich the regulatory dimensionality of functional materials. Herein, a colossal 3D electrical anisotropy of layered MAB-phase MoAlB single crystal is introduced and dissected. Using high-temperature metal-solution method, high-quality MoAlB single crystals are obtained and a surprisingly strong out-of-plane ( σ a / σ b = 1.43 × 10 5 , at 2 K) and in-plane ( σ a / σ c = 12.12, at 2 K) electrical anisotropies are first observed. After a series of experimental and theoretical investigations, it is demonstrated that the 3D anisotropic crystal structure and chemical bond of MoAlB result in its 3D anisotropic phonon vibration and electronic structure, influence the corresponding electron-electron as well as electron-phonon interactions, and finally give rise to its colossal 3D anisotropy of electrical conductivity. This work experimentally and theoretically proves MoAlB single crystal possessing the 3D anisotropies of crystal structure, chemical bond, phonon vibration, electronic structure, and electrical transport, but also provides a promising platform for the future design of functionalized electronic devices as well as synthesis of new and large-sized in-plane anisotropic 2D material (MoBene).
研究领域:
凝聚态物理
·
材料科学
·
功能材料
·
晶体化学
·
纳米电子学
·
低维材料
✓ 已验证
DOI
高影响因子
Small
·
2021
·Vol. 18
·期 8
·2105599
·
IF 13.281
Wuhong Xue,Qitao Jiang,Fakun Wang,Ri He,Ruixue Pang,Huali Yang,Peng Wang,Ruilong Yang,Zhicheng Zhong,Tianyou Zhai,Xiaohong Xu
2D ferroelectrics with robust polar order in the atomic-scale thickness at room temperature are needed to miniaturize ferroelectric devices and tackle challenges imposed by traditional ferroelectrics. These materials usually have polar point group structure regarding as a prerequisite of ferroelectricity. Yet, to introduce polar structure into otherwise nonpolar 2D materials for producing ferroelectricity remains a challenge. Here, by combining first-principles calculations and experimental studies, it is reported that the native Ga vacancy-defects located in the asymmetrical sites in cubic defective semiconductor α‑Ga 2 Se 3 can induce polar structure. Meanwhile, the induced polarization can be switched in a moderate energy barrier. The switched polarization is observed in 2D α‑Ga 2 Se 3 nanoflakes of ≈4 nm with a high switching temperature up to 450 K. Such polarization switching could arise from the displacement of Ga vacancy between neighboring asymmetrical sites by applying an electric field. This work removes the point group limit for ferroelectricity, expanding the range of 2D ferroelectrics into the native defective semiconductors.
研究领域:
材料科学
·
凝聚态物理
·
纳米电子学
·
功能材料
·
半导体物理
✓ 已验证
DOI
高影响因子
ACS Applied Nano Materials
·
2022
·
IF 6.14
Ying Zhang,Shasha Wang,Guojing Hu,Haoliang Huang,Bo Zheng,Yuehui Zhou,Yan Feng,Xiang Ma,Junfeng He,Yalin Lu,Meng Gu,Yu-Lun Chueh,Guorui Chen,Bin Xiang
Graphene devices are susceptible to the surrounding environment. For example, the substrate in contact with graphene influences the device performance because the carriers are confined in two-dimensional (2D) atomic thickness. However, 2D van der Waals dielectric materials used as an interface modifier can provide a path to improve the device quality. In this paper, we report enhanced mobility of up to 540 000 cm2 V–1 s–1 in monolayer graphene sandwiched between two layers of a CrOCl insulator through a dielectric shielding effect. The Shubnikov–de Haas quantum oscillation is also observed with the amplitude linearly decreasing with increasing temperature, consistent with the standard Lifshitz–Kosevich theory. More strikingly, this oscillation persists to a temperature as high as 100 K because of this enhanced mobility. Our work paves a way to improve the mobility of graphene and realize the nontrivial quantum states at high temperatures for the exploration of low-power-consumption device applications in electronics.
研究领域:
凝聚态物理
·
纳米电子学
·
量子材料
·
低功耗电子学
✓ 已验证
DOI
高影响因子
NANO LETTERS
·
2018
·
IF 12.08
Huifang Ma,Peng Chen,Bo Li,Jia Li,Ruoqi Ai,Zhengwei Zhang,Guangzhuang Sun,Kangkang Yao,Zhaoyang Lin,Bei Zhao,Ruixia Wu,Xuwan Tang,Xidong Duan,Xiangfeng Duan
The recent discovery of topological semimetals has stimulated extensive research interest due to their unique electronic properties and novel transport properties related to a chiral anomaly. However, the studies to date are largely limited to bulk crystals and exfoliated flakes. Here, we report the controllable synthesis of ultrathin two-dimensional (2D) platinum telluride (PtTe2) nanosheets with tunable thickness and investigate the thickness-dependent electronic properties. We show that PtTe2 nanosheets can be readily grown, using a chemical vapor deposition approach, with a hexagonal or triangular geometry and a lateral dimension of up to 80 μm, and the thickness of the nanosheets can be systematically tailored from over 20 to 1.8 nm by reducing the growth temperature or increasing the flow rate of the carrier gas. X-ray-diffraction, transmission-electron microscopy, and electron-diffraction studies confirm that the resulting 2D nanosheets are high-quality single crystals. Raman spectroscopic studies show characteristics Eg and A1g vibration modes at ∼109 and ∼155 cm–1, with a systematic red shift with increasing nanosheet thickness. Electrical transport studies show the 2D PtTe2 nanosheets display an excellent conductivity up to 2.5 × 106 S m–1 and show strong thickness-tunable electrical properties, with both the conductivity and its temperature dependence varying considerably with the thickness. Moreover, 2D PtTe2 nanosheets show an extraordinary breakdown current density up to 5.7 × 107 A/cm2, the highest breakdown current density achieved in 2D metallic transition-metal dichalcogenides to date.
研究领域:
凝聚态物理
·
材料科学
·
纳米电子学
·
拓扑半金属
·
二维材料
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2019
·
IF 8.456
Jiajun Chen,Kai Shao,Weihuang Yang,Weiqing Tang,Jiangpeng Zhou,Qinming He,Yaping Wu,Chunmiao Zhang,Xu Li,Xu Yang,Zhiming Wu,Junyong Kang
Two-dimensional transition-metal dichalcogenides (TMDCs) possess unique electronic and optical properties, which open up a new opportunity for atomically thin optoelectronic devices. Synthesizing large-scale monolayer TMDCs on the SiO2/Si substrate is crucial for practical applications, however, it remains a big challenge. In this work, a method which combines chemical vapor deposition (CVD) and thermal evaporation was employed to grow monolayer tungsten disulfide (WS2) crystals. Through controlling the density and the distribution of W precursors, a wafer-scale continuous uniform WS2 film was achieved, with the structural and spectral characterizations confirming a monolayer configuration and a high crystalline quality. Wafer-scale field-effect transistor arrays based on the monolayer WS2 were fabricated. The devices show superior electrical performances, and the maximal mobility is almost 1 order of magnitude higher than those of CVD-grown large-scale TMDC devices reported so far.
研究领域:
材料科学
·
纳米电子学
·
半导体器件
·
薄膜技术
✓ 已验证
DOI
高影响因子
ACS Applied Nano Materials
·
2021
·
IF 5.097
Pengtao Tang,Haibo Shu,Mingjun Yang,Mingsong Zhang,Chuangwei Sheng,Pei Liang,Dan Cao,Xiaoshuang Chen
Monolayer transition metal dichalcogenide (TMD) alloys with tunable band gaps exhibit huge potential in nanoelectronics, optoelectronics, and photonics. The scalable production of uniform atomically thin TMD alloys is a key step for the realization of their device applications but remains a large challenge so far. Here, we report oxygen-assisted chemical vapor deposition (CVD) of uniform atomically thin MoS2(1–x)Se2x semiconductor alloys via a vertical Mo-precursor supply strategy. The growth scheme leads to the formation of highly crystalline MoS2(1–x)Se2x monolayer films within a short growth time of 8 min, which benefits from a stable and homogeneous Mo-precursor feeding environment and the synergic effect of NaBr and oxygen carrier on the growth. The high-resolution spectral characterizations and density functional theory calculations demonstrate that the chemical composition of the as-grown MoS2(1–x)Se2x monolayers can be continuously tuned from x = 0 to 1, leading to the corresponding band gap being gradually changed from 1.81 to 1.55 eV. This work provides an efficient strategy to obtain large-area uniform MoS2(1–x)Se2x monolayer alloys with tunable compositions and optical properties, which is essential for driving their applications in various functional optoelectronic devices, especially for high-performance flexible photodetectors.
研究领域:
材料科学
·
纳米电子学
·
光电子学
·
光子学
·
半导体合金
·
薄膜生长
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2020
·
IF 8.758
Miaomiao Yu,Yunxia Hu,Feng Gao,Mingjin Dai,Lifeng Wang,PingAn Hu,Wei Feng
Multilayer InSe is a promising material for high-performance optoelectronic applications because of its small direct band gap and good light absorption. However, as a photoconductive photodetector, multilayer InSe photodetectors endure large dark current and high driving power. In this work, we study the electrical properties of InGaSe alloys and demonstrate the high-performance devices based on multilayer InSe–In0.24Ga0.76Se van der Waals heterojunctions (vdWHs). The electrical properties of InGaSe alloy samples strongly depend on the ratio of In to Ga, and the In0.24Ga0.76Se alloy shows a p-type transport behavior. More importantly, a multilayer InSe–In0.24Ga0.76Se vdWH device is demonstrated as a high-performance forward diode, photodiode, and self-powered photodetector (SPPD). The multilayer InSe–In0.24Ga0.76Se diode shows a high forward rectification ratio of over 103 without gate modulation at room temperature, which is superior to most of the multilayer vdWH devices. Moreover, the vdWH photodiode has a broadband photoresponse spectrum (400–1000 nm) and a high-performance photoresponse. The light switching ratio, detectivity (D*), and responsivity (R) are 103, 1012 Jones, and 49 A W–1 for 400 nm illumination, respectively. Furthermore, the vdWH SPPD also shows a sensitive photoresponse to a broadband spectrum of 400–1000 nm. Our work offers an opportunity for multilayer vdWH device applications in high-performance electronic and optoelectronic devices.
研究领域:
光电子学
·
材料科学
·
纳米电子学
·
半导体物理
·
二维材料
✓ 已验证
DOI
高影响因子
ACS Applied Nano Materials
·
2023
·
IF 5.9
Juan Gao,Qin Gao,Jiangshun Huang,Xiaoyue Feng,Xueli Geng,Haoze Li,Guoxing Wang,Bo Liang,Xueliang Chen,Yuanzhao Su,Mei Wang,Zhisong Xiao,Paul K. Chu,Anping Huang
Perovskite-based memristors have attracted much attention in synaptic simulation due to their outstanding electrical properties and promising potential in neuromorphic computing (NC). In this work, inorganic lead-free perovskite-based memristors composed of Ag/Cs3Bi2–xLixI9–2x (CBLxI)/ITO (x = 0, 0.2, 0.4, 0.6) are fabricated, and the electrical properties, such as endurance, on/off ratio, and retention time, are determined. It is found that the device with x = 0.4 shows good characteristics, such as a set voltage of −0.1 V and a retention time of 104 s. The multilevel storage performance is investigated, and multiple synaptic characteristics, such as paired-pulse facilitation (PPF), spike-voltage-dependent plasticity (SVDP), spike-width-dependent plasticity (SWDP), spike-timing-dependent plasticity (STDP), and learning–forgetting, are simulated. The conductive mechanism of the device is analyzed and discussed with an analogy to natural volcanic rocks, which also have a large surface area, high adsorption, and high chemical inertness. An artificial neural network (ANN) based on the potentiation/depression characteristics is designed and analyzed theoretically, and a pattern recognition rate of 94.25% is accomplished. The strategy and results described in this paper provide insights into the development of nonvolatile memory devices boding well for the adoption of neuromorphic computing for image recognition.
研究领域:
材料科学
·
神经形态工程
·
电子器件
·
人工智能
·
纳米电子学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2020
·
IF 8.758
Xinglai Zhang,Jing Li,Zongyi Ma,Jian Zhang,Bing Leng,Baodan Liu
Molybdenum disulfide (MoS2) as a typical two-dimensional (2D) transition-metal dichalcogenide exhibits great potential applications for the next-generation nanoelectronics such as photodetectors. However, most MoS2-based photodetectors hold obvious disadvantages including a narrow spectral response in the visible region, poor photoresponsivity, and slow response speed. Here, for the first time, we report the design of a two-dimensional MoS2/GaN van der Waals (vdWs) heterostructure photodetector consisting of few-layer p-type MoS2 and very thin n-type GaN flakes. Thanks to the good crystal quality of the 2D-GaN flake and the built-in electric field in the interface depletion region of the MoS2/GaN p–n junction, photogenerated carriers can be rapidly separated and more excitons are collected by electrodes toward the high photoresponsivity of 328 A/W and a fast response time of 400 ms under the illumination of 532 nm light, which is seven times faster than pristine MoS2 flake. Additionally, the response spectrum of the photodetector is also broadened to the UV region with a high photoresponsivity of 27.1 A/W and a fast response time of 300 ms after integrating with the 2D-GaN flake, exhibiting an advantageous synergetic effect. These excellent performances render MoS2/GaN vdWs heterostructure photodetectors as promising and competitive candidates for next-generation optoelectronic devices.
研究领域:
纳米电子学
·
光电子学
·
材料科学
·
半导体物理
·
光子学
✓ 已验证
DOI
高影响因子
ACS Applied Nano Materials
·
2018
·
IF 0
Shuhui Tao,Qian Zhang,Chunhui He,Xiangfei Lin,Ruochen Xie,Cezhou Zhao,Chun Zhao,Alexander Smogunov,Yannick J. Dappe,Richard J. Nichols,Li Yang
In this study, we have determined the electrical properties of amine- and thiol-terminated poly(p-phenylene) molecular wires bound either between two gold electrode contacts (Au/Au) or between a gold contact and a graphene electrode (Au/graphene). These different junctions were studied using a scanning tunneling microscopy (STM) and a noncontact method for forming the molecular bridges (the I(s) technique, where I = current and s = distance). We show that for these molecular targets, junctions formed with Au/Au electrodes have higher conductance than those formed with Au/graphene electrodes. The measured conductance decays exponentially with an increase in the number of phenyl rings, giving a decay constant that is similar for amine- and thiol-terminated molecular junctions with the Au/graphene system. This work reveals that poly(p-phenylene) chains present similar electronic properties when coupled to either gold or graphene electrodes, independently of whether the anchoring group is amine or thiol(ate), and that the transport properties are essentially dominated by the intrinsic molecular properties.
研究领域:
分子电子学
·
纳米电子学
·
凝聚态物理
·
表面科学
✓ 已验证
DOI
Journal of Physical Chemistry C
·
2020
·
IF 4.189
Yecheng Cheng,Pengtao Tang,Pei Liang,Xueyin Liu,Dan Cao,Xiaoshuang Chen,Haibo Shu
The rational control of the nucleation and growth kinetics to enable the high-quality growth of two-dimensional (2D) semiconducting metal chalcogenide heterostructures is a key step for the realization of their applications in nanoelectronics and optoelectronics. Here, we report a facile one-step chemical vapor deposition synthesis of 2D SnS–SnS2 heterostructures with controlled interfacial structures and stacking configurations via tuning S-precursor concentration during the growth. We demonstrate that the change of S-precursor concentration can drive growth transition from vertically stacking SnS2/SnS van der Waals heterostructures to SnS/SnS2 core–shell structures with both the lateral and vertical interfaces. Such a transition originates from a delicate competition between the nucleation of SnS and SnS2. High-resolution spectroscopy measurements and density functional theory (DFT) calculations reveal these SnS–SnS2 heterostructures with the type-II band alignment, and the measured valence and conduction band offsets are 1.33 and 0.34 eV for vertical SnS2/SnS heterostructures and 1.43 and 0.54 eV for SnS/SnS2 core–shell ones, respectively. This work provides an efficient strategy to control the growth of 2D SnS–SnS2 heterostructures for optoelectronic applications, such as photodetectors and solar cells.
研究领域:
材料科学
·
纳米电子学
·
光电子学
·
半导体异质结构
·
凝聚态物理
✓ 已验证
DOI
高影响因子
ACS Applied Electronic Materials
·
2022
·
IF 4.494
Yu Chang,Haofei Cong,Ruifu Zhou,Wenxin Zhang,Yuanbin Qin,Xuhai Liu,Fengyun Wang
Multiterminal artificial synapses constitute a vibrant research field in the hardware of artificial intelligence. Arrays consisting of one-dimensional nanowire can render artificial synapses with enhanced electrical properties, exhibiting potential for highly compact circuit integration. Herein, we fabricated three-terminal electrolyte-gated synaptic transistors based on indium zinc oxide (InZnO) nanowire arrays (NWAs) via a low-cost electrospinning technique combined with a facile nanowire transfer process. The nanowire diameter can be as narrow as 40 nm, presenting an opportunity for low-cost compact circuit integration. Moreover, based on the synaptic transistors composed of InZnO NWAs and a LiClO4 electrolyte, we obtained figures of merit of artificial synapses, such as the excitatory postsynaptic current, paired-pulse facilitation, high-pass filtering capability, and long-term potentiation. Furthermore, we systematically compared the electrical performance of NWAs with the randomly aligned InZnO nanowire networks (NWNs), and the electrical characteristics of NWA synaptic transistors are superior compared with those of the NWN counterpart. In addition, an artificial neural network for handwritten digit recognition based on the experimentally measured potentiation/depression characteristics has been simulated with a recognition accuracy of 93.1%. Our study demonstrates the opportunity to realize low-power artificial synapses with aligned nanowire arrays obtained from cost-effective fabrication techniques.
研究领域:
神经形态工程
·
纳米电子学
·
材料科学
·
人工智能硬件
·
薄膜晶体管
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）