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1.
Qijie Liang Qixing Wang Qian Zhang Jingxuan Wei Sharon Xiaodai Lim Rui Zhu Junxiong Hu Wei Wei Chengkuo Lee ChorngHaur Sow Wenjing Zhang Andrew Thye Shen Wee 《Advanced materials (Deerfield Beach, Fla.)》2019,31(24)
Photodetection over a broad spectral range is crucial for optoelectronic applications such as sensing, imaging, and communication. Herein, a high‐performance ultra‐broadband photodetector based on PdSe2 with unique pentagonal atomic structure is reported. The photodetector responds from visible to mid‐infrared range (up to ≈4.05 µm), and operates stably in ambient and at room temperature. It promises improved applications compared to conventional mid‐infrared photodetectors. The highest responsivity and external quantum efficiency achieved are 708 A W?1 and 82 700%, respectively, at the wavelength of 1064 nm. Efficient optical absorption beyond 8 µm is observed, indicating that the photodetection range can extend to longer than 4.05 µm. Owing to the low crystalline symmetry of layered PdSe2, anisotropic properties of the photodetectors are observed. This emerging material shows potential for future infrared optoelectronics and novel devices in which anisotropic properties are desirable. 相似文献
2.
Chemical Patterning of High‐Mobility Semiconducting 2D Bi2O2Se Crystals for Integrated Optoelectronic Devices
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Jinxiong Wu Yujing Liu Zhenjun Tan Congwei Tan Jianbo Yin Tianran Li Teng Tu Hailin Peng 《Advanced materials (Deerfield Beach, Fla.)》2017,29(44)
Patterning of high‐mobility 2D semiconducting materials with unique layered structures and superb electronic properties offers great potential for batch fabrication and integration of next‐generation electronic and optoelectronic devices. Here, a facile approach is used to achieve accurate patterning of 2D high‐mobility semiconducting Bi2O2Se crystals using dilute H2O2 and protonic mixture acid as efficient etchants. The 2D Bi2O2Se crystal after chemical etching maintains a high Hall mobility of over 200 cm2 V?1 s?1 at room temperature. Centimeter‐scale well‐ordered arrays of 2D Bi2O2Se with tailorable configurations are readily obtained. Furthermore, integrated photodetectors based on 2D Bi2O2Se arrays are fabricated, exhibiting excellent air stability and high photoresponsivity of ≈2000 A W?1 at 532 nm. These results are one step towards the practical application of ultrathin 2D integrated digital and optoelectronic circuits. 相似文献
3.
Near‐Infrared Photodetectors Based on MoTe2/Graphene Heterostructure with High Responsivity and Flexibility
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Wenzhi Yu Shaojuan Li Yupeng Zhang Weiliang Ma Tian Sun Jian Yuan Kai Fu Qiaoliang Bao 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(24)
2D transition metal dichalcogenides (TMDCs) have attracted considerable attention due to their impressively high performance in optoelectronic devices. However, efficient infrared (IR) photodetection has been significantly hampered because the absorption wavelength range of most TMDCs lies in the visible spectrum. In this regard, semiconducting 2D MoTe2 can be an alternative choice owing to its smaller band gap ≈1 eV from bulk to monolayer and high carrier mobility. Here, a MoTe2/graphene heterostructure photodetector is demonstrated for efficient near‐infrared (NIR) light detection. The devices achieve a high responsivity of ≈970.82 A W?1 (at 1064 nm) and broadband photodetection (visible‐1064 nm). Because of the effective photogating effect induced by electrons trapped in the localized states of MoTe2, the devices demonstrate an extremely high photoconductive gain of 4.69 × 108 and detectivity of 1.55 × 1011 cm Hz1/2 W?1. Moreover, flexible devices based on the MoTe2/graphene heterostructure on flexible substrate also retains a good photodetection ability after thousands of times bending test (1.2% tensile strain), with a high responsivity of ≈60 A W?1 at 1064 nm at V DS = 1 V, which provides a promising platform for highly efficient, flexible, and low cost broadband NIR photodetectors. 相似文献
4.
Rujia Zou Zhenyu Zhang Qian Liu Junqing Hu Liwen Sang Meiyong Liao Wenjun Zhang 《Small (Weinheim an der Bergstrasse, Germany)》2014,10(9):1848-1856
Fabrication of a high‐temperature deep‐ultraviolet photodetector working in the solar‐blind spectrum range (190–280 nm) is a challenge due to the degradation in the dark current and photoresponse properties. Herein, β‐Ga2O3 multi‐layered nanobelts with (l00) facet‐oriented were synthesized, and were demonstrated for the first time to possess excellent mechanical, electrical properties and stability at a high temperature inside a TEM studies. As‐fabricated DUV solar‐blind photodetectors using (l00) facet‐oriented β‐Ga2O3 multi‐layered nanobelts demonstrated enhanced photodetective performances, that is, high sensitivity, high signal‐to‐noise ratio, high spectral selectivity, high speed, and high stability, importantly, at a temperature as high as 433 K, which are comparable to other reported semiconducting nanomaterial photodetectors. In particular, the characteristics of the photoresponsivity of the β‐Ga2O3 nanobelt devices include a high photoexcited current (>21 nA), an ultralow dark current (below the detection limit of 10?14 A), a fast time response (<0.3 s), a high Rλ (≈851 A/W), and a high EQE (~4.2 × 103). The present fabricated facet‐oriented β‐Ga2O3 multi‐layered nanobelt based devices will find practical applications in photodetectors or optical switches for high‐temperature environment. 相似文献
5.
Xue Yang Xi Zhou Lei Li Ning Wang Rui Hao Yanan Zhou Hua Xu Yingtao Li Guangming Zhu Zemin Zhang Junru Wang Qingliang Feng 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(28):2206590
High operating temperature (HOT) broadband photodetectors are urgently necessary for extreme condition applications in infrared-guided missiles, infrared night vision, fire safety imaging, and space exploration sensing. However, conventional photodetectors show dramatic carrier mobility decreases and carrier losses with low photoresponsivity at HOT due to the increased carrier scattering in channels at high temperatures. Herein, the HOT broadband photodetectors from room temperature to 470 K are developed for the first time by large-area black phosphorus (BP)/PtSe2 films device arrays via a depletion-enhanced photocarrier dynamics strategy. Attributed to the 2D Schottky junction at BP/PtSe2 interface and resulting in full depleted working channels, the BP/PtSe2 photodetector arrays exhibit high tolerance to carrier mobility decrease during the increasing operating temperature in a wide wavelength range from 532 to 2200 nm. Thus, the photodetector shows a state-of-the-art operating temperature at 470 K with the photo-responsivity (R) and specific detectivity (D*) of 25 A W−1 and 6.4 × 1011 Jones under 1850 nm illumination, respectively. Moreover, BP/PtSe2 photodetector arrays show high-uniformity photo-response in a large area. This work provides new strategies for high-performance broadband photodetector arrays with HOT by Schottky junction of large-area BP/PtSe2 films. 相似文献
6.
High Detectivity and Transparent Few‐Layer MoS2/Glassy‐Graphene Heterostructure Photodetectors
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Hao Xu Xiaoyu Han Xiao Dai Wei Liu Jiang Wu Juntong Zhu Dongyoung Kim Guifu Zou Kimberley A. Sablon Andrei Sergeev Zhengxiao Guo Huiyun Liu 《Advanced materials (Deerfield Beach, Fla.)》2018,30(13)
Layered van der Waals heterostructures have attracted considerable attention recently, due to their unique properties both inherited from individual two‐dimensional (2D) components and imparted from their interactions. Here, a novel few‐layer MoS2/glassy‐graphene heterostructure, synthesized by a layer‐by‐layer transfer technique, and its application as transparent photodetectors are reported for the first time. Instead of a traditional Schottky junction, coherent ohmic contact is formed at the interface between the MoS2 and the glassy‐graphene nanosheets. The device exhibits pronounced wavelength selectivity as illuminated by monochromatic lights. A responsivity of 12.3 mA W?1 and detectivity of 1.8 × 1010 Jones are obtained from the photodetector under 532 nm light illumination. Density functional theory calculations reveal the impact of specific carbon atomic arrangement in the glassy‐graphene on the electronic band structure. It is demonstrated that the band alignment of the layered heterostructures can be manipulated by lattice engineering of 2D nanosheets to enhance optoelectronic performance. 相似文献
7.
Ultrahigh‐Performance Self‐Powered Flexible Double‐Twisted Fibrous Broadband Perovskite Photodetector
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Haoxuan Sun Wei Tian Fengren Cao Jie Xiong Liang Li 《Advanced materials (Deerfield Beach, Fla.)》2018,30(21)
Self‐powered flexible photodetectors without an external power source can meet the demands of next‐generation portable and wearable nanodevices; however, the performance is far from satisfactory becuase of the limited match of flexible substrates and light‐sensitive materials with proper energy levels. Herein, a novel self‐powered flexible fiber‐shaped photodetector based on double‐twisted perovskite–TiO2–carbon fiber and CuO–Cu2O–Cu wire is designed and fabricated. The device shows an ultrahigh detectivity of 2.15 × 1013 Jones under the illumination of 800 nm light at zero bias. CuO–Cu2O electron block bilayer extends response range of perovskite from 850 to 1050 nm and suppresses dark current down to 10?11 A. The fast response speed of less than 200 ms is nearly invariable after dozens of cycles of bending at the extremely 90 bending angle, demonstrating excellent flexibility and bending stability. These parameters are comparable and even better than reported flexible and even rigid photodetectors. The present results suggest a promising strategy to design photodetectors with integrated function of self‐power, flexibility, and broadband response. 相似文献
8.
Self‐Assembled Heterostructures: Selective Growth of Metallic Nanoparticles on V2–VI3 Nanoplates
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Chaochao Dun Corey A. Hewitt Qi Li Yang Guo Qike Jiang Junwei Xu Gabriel Marcus Drew C. Schall David L. Carroll 《Advanced materials (Deerfield Beach, Fla.)》2017,29(38)
Precise control of the selective growth of heterostructures with specific composition and functionalities is an emerging and extremely challenging topic. Here, the first investigation of the difference in binding energy between a series of metal–semiconductor heterostructures based on layered V2–VI3 nanostructures is investigated by means of density functional theory. All lateral configurations show lower formation energy compared with that of the vertical ones, implying the selective growth of metal nanoparticles. The simulation results are supported by the successful fabrication of self‐assembled Ag/Cu‐nanoparticle‐decorated p‐type Sb2Te3 and n‐type Bi2Te3 nanoplates at their lateral sites through a solution reaction. The detailed nucleation–growth kinetics are well studied with controllable reaction times and precursor concentrations. Accompanied by the preserved topological structure integrity and electron transfer on the semiconductor host, exceptional properties such as dramatically increased electrical conductivity are observed thanks to the pre‐energy‐filtering effect before carrier injection. A zigzag thermoelectric generator is built using Cu/Ag‐decorated Sb2Te3 and Bi2Te3 as p–n legs to utilize the temperature gradient in the vertical direction. Synthetic approaches using similar chalcogenide nanoplates as building blocks, as well as careful control of the dopant metallic nanoparticles or semiconductors, are believed to be broadly applicable to other heterostructures with novel applications. 相似文献
9.
Solution‐Processed 3D RGO–MoS2/Pyramid Si Heterojunction for Ultrahigh Detectivity and Ultra‐Broadband Photodetection
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Peng Xiao Jie Mao Ke Ding Wenjin Luo Weida Hu Xiujuan Zhang Xiaohong Zhang Jiansheng Jie 《Advanced materials (Deerfield Beach, Fla.)》2018,30(31)
Molybdenum disulfide (MoS2), a typical 2D metal dichalcogenide (2DMD), has exhibited tremendous potential in optoelectronic device applications, especially in photodetection. However, due to the weak light absorption of planar mono‐/multilayers, limited cutoff wavelength edge, and lack of high‐quality junctions, most reported MoS2‐based photodetectors show undesirable performance. Here, a structurized 3D heterojunction of RGO–MoS2/pyramid Si is demonstrated via a simple solution‐processing method. Owing to the improved light absorption by the pyramid structure, the narrowed bandgap of the MoS2 by the imperfect crystallinity, and the enhanced charge separation/transportation by the inserted reduced graphene oxide (RGO), the assembled photodetector exhibits excellent performance in terms of a large responsivity of 21.8 A W?1, extremely high detectivity up to 3.8 × 1015 Jones (Jones = cm Hz1/2 W?1) and ultrabroad spectrum response ranging from 350 nm (ultraviolet) to 4.3 µm (midwave infrared). These device parameters represent the best results for MoS2‐based self‐driven photodetectors, and the detectivity value sets a new record for the 2DMD‐based photodetectors reported thus far. Prospectively, the design of novel 3D heterojunction can be extended to other 2DMDs, opening up the opportunities for a host of high‐performance optoelectronic devices. 相似文献
10.
Feng Zhou Ibrahim Abdelwahab Kai Leng Kian Ping Loh Wei Ji 《Advanced materials (Deerfield Beach, Fla.)》2019,31(48)
Two‐dimensional (2D) perovskites have proved to be promising semiconductors for photovoltaics, photonics, and optoelectronics. Here, a strategy is presented toward the realization of highly efficient, sub‐bandgap photodetection by employing excitonic effects in 2D Ruddlesden–Popper‐type halide perovskites (RPPs). On near resonance with 2D excitons, layered RPPs exhibit degenerate two‐photon absorption (D‐2PA) coefficients as giant as 0.2–0.64 cm MW?1. 2D RPP‐based sub‐bandgap photodetectors show excellent detection performance in the near‐infrared (NIR): a two‐photon‐generated current responsivity up to 1.2 × 104 cm2 W?2 s?1, two orders of magnitude greater than InAsSbP‐pin photodiodes; and a dark current as low as 2 pA at room temperature. More intriguingly, layered‐RPP detectors are highly sensitive to the light polarization of incoming photons, showing a considerable anisotropy in their D‐2PA coefficients (β[001]/β[011] = 2.4, 70% larger than the ratios reported for zinc‐blende semiconductors). By controlling the thickness of the inorganic quantum well, it is found that layered RPPs of (C4H9NH3)2(CH3NH3)Pb2I7 can be utilized for three‐photon photodetection in the NIR region. 相似文献
11.
Ultra‐Broadband Flexible Photodetector Based on Topological Crystalline Insulator SnTe with High Responsivity
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Jie Yang Wenzhi Yu Zhenghui Pan Qiang Yu Qing Yin Lei Guo Yanfei Zhao Tian Sun Qiaoliang Bao Kai Zhang 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(37)
Topological crystalline insulators (TCIs) are predicted to be a promising candidate material for ultra‐broadband photodetectors ranging from ultraviolet (UV) to terahertz (THz) due to its gapless surface state and narrow bulk bandgap. However, the low responsivity of TCIs‐based photodetectors limits their further applications. In this regard, a high‐performance photodetector based on SnTe, a recently developed TCI, working in a broadband wavelength range from deep UV to mid‐IR with high responsivity is reported. By taking advantage of the strong light absorption and small bandgap of SnTe, photodetectors based on the as‐grown SnTe crystalline nanoflakes as well as specific short channel length achieve a high responsivity (71.11 A W?1 at 254 nm, 49.03 A W?1 at 635 nm, 10.91 A W?1 at 1550 nm, and 4.17 A W?1 at 4650 nm) and an ultra‐broad spectral response (254–4650 nm) simultaneously. Moreover, for the first time, a durable flexible SnTe photodetector fabricated directly on a polyethylene terephthalate film is demonstrated. These results prove the great potential of TCIs as a promising material for integrated and flexible optoelectronic devices. 相似文献
12.
Chemical Intercalation of Topological Insulator Grid Nanostructures for High‐Performance Transparent Electrodes
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Yunfan Guo Jinyuan Zhou Yujing Liu Xu Zhou Fengrui Yao Congwei Tan Jinxiong Wu Li Lin Kaihui Liu Zhongfan Liu Hailin Peng 《Advanced materials (Deerfield Beach, Fla.)》2017,29(44)
2D layered nanomaterials with strong covalent bonding within layers and weak van der Waals' interactions between layers have attracted tremendous interest in recent years. Layered Bi2Se3 is a representative topological insulator material in this family, which holds promise for exploration of the fundamental physics and practical applications such as transparent electrode. Here, a simultaneous enhancement of optical transmittancy and electrical conductivity in Bi2Se3 grid electrodes by copper‐atom intercalation is presented. These Cu‐intercalated 2D Bi2Se3 electrodes exhibit high uniformity over large area and excellent stabilities to environmental perturbations, such as UV light, thermal fluctuation, and mechanical distortion. Remarkably, by intercalating a high density of copper atoms, the electrical and optical performance of Bi2Se3 grid electrodes is greatly improved from 900 Ω sq?1, 68% to 300 Ω sq?1, 82% in the visible range; with better performance of 300 Ω sq?1, 91% achieved in the near‐infrared region. These unique properties of Cu‐intercalated topological insulator grid nanostructures may boost their potential applications in high‐performance optoelectronics, especially for infrared optoelectronic devices. 相似文献
13.
High Performance and Stable All‐Inorganic Metal Halide Perovskite‐Based Photodetectors for Optical Communication Applications
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Chunxiong Bao Jie Yang Sai Bai Weidong Xu Zhibo Yan Qingyu Xu Junming Liu Wenjing Zhang Feng Gao 《Advanced materials (Deerfield Beach, Fla.)》2018,30(38)
Photodetectors are critical parts of an optical communication system for achieving efficient photoelectronic conversion of signals, and the response speed directly determines the bandwidth of the whole system. Metal halide perovskites, an emerging class of low‐cost solution‐processed semiconductors, exhibiting strong optical absorption, low trap states, and high carrier mobility, are widely investigated in photodetection applications. Herein, through optimizing the device engineering and film quality, high‐performance photodetectors based on all‐inorganic cesium lead halide perovskite (CsPbIxBr3–x), which simultaneously possess high sensitivity and fast response, are demonstrated. The optimized devices processed from CsPbIBr2 perovskite show a practically measured detectable limit of about 21.5 pW cm?2 and a fast response time of 20 ns, which are both among the highest reported device performance of perovskite‐based photodetectors. Moreover, the photodetectors exhibit outstanding long‐term environmental stability, with negligible degradation of the photoresponse property after 2000 h under ambient conditions. In addition, the resulting perovskite photodetector is successfully integrated into an optical communication system and its applications as an optical signal receiver on transmitting text and audio signals is demonstrated. The results suggest that all‐inorganic metal halide perovskite‐based photodetectors have great application potential for optical communication. 相似文献
14.
Zhi‐Qian Wu Jing‐Liang Yang Nallappagar K. Manjunath Yue‐Jiao Zhang Si‐Rui Feng Yang‐Hua Lu Jiang‐Hong Wu Wei‐Wei Zhao Cai‐Yu Qiu Jian‐Feng Li Shi‐Sheng Lin 《Advanced materials (Deerfield Beach, Fla.)》2018,30(27)
2D materials hold great potential for designing novel electronic and optoelectronic devices. However, 2D material can only absorb limited incident light. As a representative 2D semiconductor, monolayer MoS2 can only absorb up to 10% of the incident light in the visible, which is not sufficient to achieve a high optical‐to‐electrical conversion efficiency. To overcome this shortcoming, a “gap‐mode” plasmon‐enhanced monolayer MoS2 fluorescent emitter and photodetector is designed by squeezing the light‐field into Ag shell‐isolated nanoparticles–Au film gap, where the confined electromagnetic field can interact with monolayer MoS2. With this gap‐mode plasmon‐enhanced configuration, a 110‐fold enhancement of photoluminescence intensity is achieved, exceeding values reached by other plasmon‐enhanced MoS2 fluorescent emitters. In addition, a gap‐mode plasmon‐enhanced monolayer MoS2 photodetector with an 880% enhancement in photocurrent and a responsivity of 287.5 A W?1 is demonstrated, exceeding previously reported plasmon‐enhanced monolayer MoS2 photodetectors. 相似文献
15.
Sichao Du Wei Lu Ayaz Ali Pei Zhao Khurram Shehzad Hongwei Guo Lingling Ma Xuemei Liu Xiaodong Pi Peng Wang Hehai Fang Zhen Xu Chao Gao Yaping Dan Pingheng Tan Hongtao Wang Cheng‐Te Lin Jianyi Yang Shurong Dong Zhiyuan Cheng Erping Li Wenyan Yin Jikui Luo Bin Yu Tawfique Hasan Yang Xu Weida Hu Xiangfeng Duan 《Advanced materials (Deerfield Beach, Fla.)》2017,29(22)
High‐performance photodetectors operating over a broad wavelength range from ultraviolet, visible, to infrared are of scientific and technological importance for a wide range of applications. Here, a photodetector based on van der Waals heterostructures of graphene and its fluorine‐functionalized derivative is presented. It consistently shows broadband photoresponse from the ultraviolet (255 nm) to the mid‐infrared (4.3 µm) wavelengths, with three orders of magnitude enhanced responsivity compared to pristine graphene photodetectors. The broadband photodetection is attributed to the synergistic effects of the spatial nonuniform collective quantum confinement of sp2 domains, and the trapping of photoexcited charge carriers in the localized states in sp3 domains. Tunable photoresponse is achieved by controlling the nature of sp3 sites and the size and fraction of sp3/sp2 domains. In addition, the photoresponse due to the different photoexcited‐charge‐carrier trapping times in sp2 and sp3 nanodomains is determined. The proposed scheme paves the way toward implementing high‐performance broadband graphene‐based photodetectors. 相似文献
16.
Hassan Ali Yunyan Zhang Jing Tang Kai Peng Sibai Sun Yue Sun Feilong Song Attia Falak Shiyao Wu Chenjiang Qian Meng Wang Zhanchun Zuo Kui‐Juan Jin Ana M. Sanchez Huiyun Liu Xiulai Xu 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(17)
Defects are detrimental for optoelectronics devices, such as stacking faults can form carrier‐transportation barriers, and foreign impurities (Au) with deep‐energy levels can form carrier traps and nonradiative recombination centers. Here, self‐catalyzed p‐type GaAs nanowires (NWs) with a pure zinc blende (ZB) structure are first developed, and then a photodetector made from these NWs is fabricated. Due to the absence of stacking faults and suppression of large amount of defects with deep energy levels, the photodetector exhibits room‐temperature high photoresponsivity of 1.45 × 105 A W?1 and excellent specific detectivity (D*) up to 1.48 × 1014 Jones for a low‐intensity light signal of wavelength 632.8 nm, which outperforms previously reported NW‐based photodetectors. These results demonstrate these self‐catalyzed pure‐ZB GaAs NWs to be promising candidates for optoelectronics applications. 相似文献
17.
Large‐Scale Synthesis of Freestanding Layer‐Structured PbI2 and MAPbI3 Nanosheets for High‐Performance Photodetection
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Changyong Lan Ruoting Dong Ziyao Zhou Lei Shu Dapan Li SenPo Yip Johnny C. Ho 《Advanced materials (Deerfield Beach, Fla.)》2017,29(39)
Recently, due to the possibility of thinning down to the atomic thickness to achieve exotic properties, layered materials have attracted extensive research attention. In particular, PbI2, a kind of layered material, and its perovskite derivatives, CH3NH3PbI3 (i.e., MAPbI3), have demonstrated impressive photoresponsivities for efficient photodetection. Herein, the synthesis of large‐scale, high‐density, and freestanding PbI2 nanosheets is demonstrated by manipulating the microenvironment during physical vapor deposition. In contrast to conventional two‐dimensional (2D) growth along the substrate surface, the essence here is the effective nucleation of microplanes with different angles relative to the in‐plane direction of underlying rough‐surfaced substrates. When configured into photodetectors, the fabricated device exhibits a photoresponsivity of 410 mA W?1, a detectivity of 3.1 × 1011 Jones, and a fast response with the rise and decay time constants of 86 and 150 ms, respectively, under a wavelength of 405 nm. These PbI2 nanosheets can also be completely converted into MAPbI3 materials via chemical vapor deposition with an improved photoresponsivity up to 40 A W?1. All these performance parameters are comparable to those of state‐of‐the‐art layered‐material‐based photodetectors, revealing the technological potency of these freestanding nanosheets for next‐generation high‐performance optoelectronics. 相似文献
18.
Yujing Liu Min Tang Mengmeng Meng Mingzhan Wang Jinxiong Wu Jianbo Yin Yubing Zhou Yunfan Guo Congwei Tan Wenhui Dang Shaoyun Huang H. Q. Xu Yong Wang Hailin Peng 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(18)
Nanostructures of ternary topological insulator (TI) Bi2Te2Se are, in principle, advantageous to the manifestation of topologically nontrivial surface states, due to significantly enhanced surface‐to‐volume ratio compared with its bulk crystals counterparts. Herein, the synthesis of 2D Bi2Te2Se crystals on mica via the van der Waals epitaxy method is explored and systematically the growth behaviors during the synthesis process are investigated. Accordingly, 2D Bi2Te2Se crystals with domain size up to 50 µm large and thickness down to 2 nm are obtained. A pronounced weak antilocalization effect is clearly observed in the 2D Bi2Te2Se crystals at 2 K. The method for epitaxial growth of 2D ternary Bi2Te2Se crystals may inspire materials engineering toward enhanced manifestation of the subtle surface states of TIs and thereby facilitate their potential applications in next‐generation spintronics. 相似文献
19.
Generalized Scheme for High Performing Photodetectors with a p‐Type 2D Channel Layer and n‐Type Nanoparticles
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Jingyuan Jia Sumin Jeon Jaeho Jeon Jiao Xu Young Jae Song Jeong Ho Cho Byoung Hun Lee Jin Dong Song Hyung‐Jun Kim Euyheon Hwang Sungjoo Lee 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(9)
A generalized scheme for the fabrication of high performance photodetectors consisting of a p‐type channel material and n‐type nanoparticles is proposed. The high performance of the proposed hybrid photodetector is achieved through enhanced photoabsorption and the photocurrent gain arising from its effective charge transfer mechanism. In this paper, the realization of this design is presented in a hybrid photodetector consisting of 2D p‐type black phosphorus (BP) and n‐type molybdenum disulfide nanoparticles (MoS2 NPs), and it is demonstrated that it exhibits enhanced photoresponsivity and detectivity compared to pristine BP photodetectors. It is found that the performance of hybrid photodetector depends on the density of NPs on BP layer and that the response time can be reduced with increasing density of MoS2 NPs. The rising and falling times of this photodetector are smaller than those of BP photodetectors without NPs. This proposed scheme is expected to work equally well for a photodetector with an n‐type channel material and p‐type nanoparticles. 相似文献
20.
Improving All‐Inorganic Perovskite Photodetectors by Preferred Orientation and Plasmonic Effect
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Yuhui Dong Yu Gu Yousheng Zou Jizhong Song Leimeng Xu Jianhai Li Jie Xue Xiaoming Li Haibo Zeng 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(40):5622-5632
All‐inorganic perovskites have high carrier mobility, long carrier diffusion length, excellent visible light absorption, and well overlapping with localized surface plasmon resonance (LSPR) of noble metal nanocrystals (NCs). The high‐performance photodetectors can be constructed by means of the intrinsic outstanding photoelectric properties, especially plasma coupling. Here, for the first time, inorganic perovskite photodetectors are demonstrated with synergetic effect of preferred‐orientation film and plasmonic with both high performance and solution process virtues, evidenced by 238% plasmonic enhancement factor and 106 on/off ratio. The CsPbBr3 and Au NC inks are assembled into high‐quality films by centrifugal‐casting and spin‐coating, respectively, which lead to the low cost and solution‐processed photodetectors. The remarkable near‐field enhancement effect induced by the coupling between Au LSPR and CsPbBr3 photogenerated carriers is revealed by finite‐difference time‐domain simulations. The photodetector exhibits a light on/off ratio of more than 106 under 532 nm laser illumination of 4.65 mW cm?2. The photocurrent increases from 0.67 to 2.77 μA with centrifugal‐casting. Moreover, the photocurrent rises from 245.6 to 831.1 μA with Au NCs plasma enhancement, leading to an enhancement factor of 238%, which is the most optimal report among the LSPR‐enhanced photodetectors, to the best of our knowledge. The results of this study suggest that all‐inorganic perovskites are promising semiconductors for high‐performance solution‐processed photodetectors, which can be further enhanced by Au plasmonic effect, and hence have huge potentials in optical communication, safety monitoring, and biological sensing. 相似文献