共查询到20条相似文献，搜索用时 15 毫秒
1.
Various photodetectors showing extremely high photoresponsivity have been frequently reported, but many of these photodetectors could not avoid the simultaneous amplification of dark current. A gate‐controlled graphene–silicon Schottky junction photodetector that exhibits a high on/off photoswitching ratio (≈104), a very high photoresponsivity (≈70 A W−1), and a low dark current in the order of µA cm−2 in a wide wavelength range (395–850 nm) is demonstrated. The photoresponsivity is ≈100 times higher than that of existing commercial photodetectors, and 7000 times higher than that of graphene‐field‐effect transistor‐based photodetectors, while the dark current is similar to or lower than that of commercial photodetectors. This result can be explained by a unique gain mechanism originating from the difference in carrier transport characteristics of silicon and graphene. 相似文献
2.
3.
4.
Qundong Fu Chao Zhu Xiaoxu Zhao Xingli Wang Apoorva Chaturvedi Chao Zhu Xiaowei Wang Qingsheng Zeng Jiadong Zhou Fucai Liu Beng Kang Tay Hua Zhang Stephen J. Pennycook Zheng Liu 《Advanced materials (Deerfield Beach, Fla.)》2019,31(1)
2D materials are considered as intriguing building blocks for next‐generation optoelectronic devices. However, their photoresponse performance still needs to be improved for practical applications. Here, ultrasensitive 2D phototransistors are reported employing chemical vapor deposition (CVD)‐grown 2D Bi2O2Se transferred onto silicon substrates with a noncorrosive transfer method. The as‐transferred Bi2O2Se preserves high quality in contrast to the serious quality degradation in hydrofluoric‐acid‐assisted transfer. The phototransistors show a responsivity of 3.5 × 104 A W?1, a photoconductive gain of more than 104, and a time response in the order of sub‐millisecond. With back gating of the silicon substrate, the dark current can be reduced to several pA. This yields an ultrahigh sensitivity with a specific detectivity of 9.0 × 1013 Jones, which is one of the highest values among 2D material photodetectors and two orders of magnitude higher than that of other CVD‐grown 2D materials. The high performance of the phototransistor shown here together with the developed unique transfer technique are promising for the development of novel 2D‐material‐based optoelectronic applications as well as integrating with state‐of‐the‐art silicon photonic and electronic technologies. 相似文献
5.
Vinh Quang Dang Tran Quang Trung Do‐Il Kim Le Thai Duy Byeong‐Ung Hwang Doo‐Won Lee Bo‐Yeong Kim Le Duc Toan Nae‐Eung Lee 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(25):3054-3065
Ultraviolet (UV) photodetectors based on ZnO nanostructure/graphene (Gr) hybrid‐channel field‐effect transistors (FETs) are investigated under illumination at various incident photon intensities and wavelengths. The time‐dependent behaviors of hybrid‐channel FETs reveal a high sensitivity and selectivity toward the near‐UV region at the wavelength of 365 nm. The devices can operate at low voltage and show excellent selectivity, high responsivity (RI ), and high photoconductive gain (G). The change in the transfer characteristics of hybrid‐channel FETs under UV light illumination allows to detect both photovoltage and photocurrent. The shift of the Dirac point (V Dirac) observed during UV exposure leads to a clearer explanation of the response mechanism and carrier transport properties of Gr, and this phenomenon permits the calculation of electron concentration per UV power density transferred from ZnO nanorods and ZnO nanoparticles to Gr, which is 9 × 1010 and 4 × 1010 per mW, respectively. The maximum values of RI and G infer from the fitted curves of RI and G versus UV intensity are 3 × 105 A W?1 and 106, respectively. Therefore, the hybrid‐channel FETs studied herein can be used as UV sensing devices with high performance and low power consumption, opening up new opportunities for future optoelectronic devices. 相似文献
6.
Cong Wang Xiaochen Ren Chunhui Xu Beibei Fu Ruihao Wang Xiaotao Zhang Rongjin Li Hongxiang Li Huanli Dong Yonggang Zhen Shengbin Lei Lang Jiang Wenping Hu 《Advanced materials (Deerfield Beach, Fla.)》2018,30(16)
Organic field‐effect transistors and near‐infrared (NIR) organic phototransistors (OPTs) have attracted world's attention in many fields in the past decades. In general, the sensitivity, distinguishing the signal from noise, is the key parameter to evaluate the performance of NIR OPTs, which is decided by responsivity and dark current. 2D single crystal films of organic semiconductors (2DCOS) are promising functional materials due to their long‐range order in spite of only few molecular layers. Herein, for the first time, air‐stable 2DCOS of n‐type organic semiconductors (a furan‐thiophene quinoidal compound, TFT‐CN) with strong absorbance around 830 nm, by the facile drop‐casting method on the surface of water are successfully prepared. Almost millimeter‐sized TFT‐CN 2DCOS are obtained and their thickness is below 5 nm. A competitive field‐effect electron mobility (1.36 cm2 V?1 s?1) and high on/off ratio (up to 108) are obtained in air. Impressively, the ultrasensitive NIR phototransistors operating at the off‐state exhibit a very low dark current of ≈0.3 pA and an ultrahigh detectivity (D*) exceeding 6 × 1014 Jones because the devices can operate in full depletion at the off‐state, superior to the majority of the reported organic‐based NIR phototransistors. 相似文献
7.
8.
Melinda Mohl Anne‐Riikka Rautio Georgies Alene Asres Milinda Wasala Prasanna Dnyaneshwar Patil Saikat Talapatra Krisztian Kordas 《Advanced Materials Interfaces》2020,7(13)
Layered transition metal chalcogenides possess properties that not only open up broad fundamental scientific enquiries but also indicate that a myriad of applications can be developed by using these materials. This is also true for tungsten‐based chalcogenides which can provide an assortment of structural forms with different electronic flairs as well as chemical activity. Such emergence of tungsten based chalcogenides as advanced forms of materials lead several investigators to believe that a tremendous opportunity lies in understanding their fundamental properties, and by utilizing that knowledge the authors may create function specific materials through structural tailoring, defect engineering, chemical modifications as well as by combining them with other layered materials with complementary functionalities. Indeed several current scientific endeavors have indicated that an incredible potential for developing these materials for future applications development in key technology sectors such as energy, electronics, sensors, and catalysis are perhaps viable. This review article is an attempt to capture this essence by providing a summary of key scientific investigations related to various aspects of synthesis, characterization, modifications, and high value applications. Finally, some open questions and a discussion on imminent research needs and directions in developing tungsten based chalcogenide materials for future applications are presented. 相似文献
9.
Jian Guo Yuan Liu Yue Ma Enbo Zhu Shannon Lee Zixuan Lu Zipeng Zhao Changhao Xu Sung‐Joon Lee Hao Wu Kirill Kovnir Yu Huang Xiangfeng Duan 《Advanced materials (Deerfield Beach, Fla.)》2018,30(21)
The family of 2D semiconductors (2DSCs) has grown rapidly since the first isolation of graphene. The emergence of each 2DSC material brings considerable excitement for its unique electrical, optical, and mechanical properties, which are often highly distinct from their 3D counterparts. To date, studies of 2DSC are majorly focused on group IV (e.g., graphene, silicene), group V (e.g., phosphorene), or group VIB compounds (transition metal dichalcogenides, TMD), and have inspired considerable effort in searching for novel 2DSCs. Here, the first electrical characterization of group IV–V compounds is presented by investigating few‐layer GeAs field‐effect transistors. With back‐gate device geometry, p‐type behaviors are observed at room temperature. Importantly, the hole carrier mobility is found to approach 100 cm2 V?1 s?1 with ON–OFF ratio over 105, comparable well with state‐of‐the‐art TMD devices. With the unique crystal structure the few‐layer GeAs show highly anisotropic optical and electronic properties (anisotropic mobility ratio of 4.8). Furthermore, GeAs based transistor shows prominent and rapid photoresponse to 1.6 µm radiation with a photoresponsivity of 6 A W?1 and a rise and fall time of ≈3 ms. This study of group IV–V 2DSC materials greatly expands the 2D family, and can enable new opportunities in functional electronics and optoelectronics based on 2DSCs. 相似文献
10.
Jia Liu Fengjing Liu Haining Liu Rui Hou Junyi Yue Jinzhong Cai Zhisheng Peng Julienne Impundu Liming Xie Yong Jun Li Lianfeng Sun 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(3)
Metal halide perovskite has attracted enhanced interest for its diverse electronic and optoelectronic applications. However, the fabrication of micro‐ or nanoscale crystalline perovskite functional devices remains a great challenge due to the fragility, solvent, and heat sensitivity of perovskite crystals. Here, a strategy is proposed to fabricate electronic and optoelectronic devices by directly growing perovskite crystals on microscale metallic structures in liquid phase. The well‐contacted perovskite/metal interfaces ensure these heterostructures serve as high‐performance field effect transistors (FETs) and excellent photodetector devices. When serving as an FET, the on/off ratio is as large as 106 and the mobility reaches up to ≈2.3 cm2 V?1 s?1. A photodetector is displayed with high photoconductive switching ratio of ≈106 and short response time of ≈4 ms. Furthermore, the photoconductive response is proved to be band‐bending‐assisted separation of photoexcited carriers at the Schottky barrier of the silver and p‐type perovskites. 相似文献
11.
12.
13.
Yi Rang Lim Jin Kyu Han Seong Ku Kim Young Bum Lee Yeoheung Yoon Seong Jun Kim Bok Ki Min Yooseok Kim Cheolho Jeon Sejeong Won Jae‐Hyun Kim Wooseok Song Sung Myung Sun Sook Lee Ki‐Seok An Jongsun Lim 《Advanced materials (Deerfield Beach, Fla.)》2018,30(5)
A facile methodology for the large‐scale production of layer‐controlled MoS2 layers on an inexpensive substrate involving a simple coating of single source precursor with subsequent roll‐to‐roll‐based thermal decomposition is developed. The resulting 50 cm long MoS2 layers synthesized on Ni foils possess excellent long‐range uniformity and optimum stoichiometry. Moreover, this methodology is promising because it enables simple control of the number of MoS2 layers by simply adjusting the concentration of (NH4)2MoS4. Additionally, the capability of the MoS2 for practical applications in electronic/optoelectronic devices and catalysts for hydrogen evolution reaction is verified. The MoS2‐based field effect transistors exhibit unipolar n‐channel transistor behavior with electron mobility of 0.6 cm2 V?1 s?1 and an on‐off ratio of ≈10³. The MoS2‐based visible‐light photodetectors are fabricated in order to evaluate their photoelectrical properties, obtaining an 100% yield for active devices with significant photocurrents and extracted photoresponsivity of ≈22 mA W?1. Moreover, the MoS2 layers on Ni foils exhibit applicable catalytic activity with observed overpotential of ≈165 mV and a Tafel slope of 133 mV dec?1. Based on these results, it is envisaged that the cost‐effective methodology will trigger actual industrial applications, as well as novel research related to 2D semiconductor‐based multifaceted applications. 相似文献
14.
Xiujuan Zhang Wei Deng Ruofei Jia Xiaohong Zhang Jiansheng Jie 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(27)
Development of high‐performance organic electronic and optoelectronic devices relies on high‐quality semiconducting crystals that have outstanding charge transport properties and long exciton diffusion length and lifetime. To achieve integrated device applications, it is a prerequisite to precisely locate the organic semiconductor crystals (OSCCs) to form a specifically patterned structure. Well‐patterned OSCCs can not only reduce leakage current and cross‐talk between neighboring devices, but also facilely integrate with other device elements and their corresponding interconnects. In this Review, general strategies for the patterning of OSCCs are summarized, and the advantages and limitations of different patterning methods are discussed. Discussion is focused on an advanced strategy for the high‐resolution and wafer‐scale patterning of OSCC by a surface microstructure‐assisted patterning method. Furthermore, the recent progress on OSCC pattern‐based integrated circuities is highlighted. Finally, the research challenges and directions of this young field are also presented. 相似文献
15.
16.
Beibei Fu Cong Wang Yantao Sun Jiarong Yao Yu Wang Fayuan Ge Fangxu Yang Zheyuan Liu Yanfeng Dang Xiaotao Zhang Xiangfeng Shao Rongjin Li Wenping Hu 《Advanced materials (Deerfield Beach, Fla.)》2019,31(35)
2D molecular crystals (2DMCs) have attracted considerable attention because of their unique optoelectronic properties and potential applications. Taking advantage of the solution processability of organic semiconductors, solution self‐assembly is considered an effective way to grow large‐area 2DMCs. However, this route is largely blocked because a precise molecular design towards 2DMCs is missing and little is known about the relationship between 2D solution self‐assembly and molecular structure. A “phase separation” molecular design strategy towards 2DMCs is proposed and layer‐by‐layer growth of millimeter‐sized monolayer or few‐layer 2DMCs is realized. High‐performance organic phototransistors are constructed based on the 2DMCs with unprecedented photosensitivity (2.58 × 107), high responsivity (1.91 × 104 A W?1), and high detectivity (4.93 × 1015 Jones). This “phase separation” molecular design strategy provides a guide for the design and synthesis of novel organic semiconductors that self‐assemble into large‐area 2DMCs for advanced organic (opto)electronics. 相似文献
17.
18.
19.