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1.
Single‐Layer MoS2 Nanosheets with Amplified Photoacoustic Effect for Highly Sensitive Photoacoustic Imaging of Orthotopic Brain Tumors
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Jingqin Chen Chengbo Liu Dehong Hu Feng Wang Haiwei Wu Xiaojing Gong Xin Liu Liang Song Zonghai Sheng Hairong Zheng 《Advanced functional materials》2016,26(47):8715-8725
Photoacoustic (PA) imaging, as a fast growing technology that combines the high contrast of light and large penetration depth of ultrasound, has demonstrated great potential for molecular imaging of cancer. However, PA molecular imaging of orthotopic brain tumors is still challenging, partially due to the limited options and insufficient sensitivity of available PA molecular probes. Here, the direct formation of single‐layer (S‐MoS2), few‐layer (F‐MoS2), and multi‐layer (M‐MoS2) nanosheets by the albumin‐assisted exfoliation without further surface modifications is reported. It is demonstrated that the PA effect of the MoS2 nanosheets is highly dependent on their layered nanostructures. Decreasing the number of nanosheet layers from M‐MoS2 to S‐MoS2 can both significantly enhance the near‐infrared light absorption and improve the elastic properties of the nanomaterial, resulting in greatly amplified PA effect. The in vitro experiments demonstrate that the prepared S‐MoS2 with excellent biocompatibility can be efficiently internalized into U87 glioma cells, producing strong PA signals for highly sensitive detection of brain tumor cells, with a detection limit of ≈100 cells. Intravenous administration of S‐MoS2 to both U87 subcutaneous and orthotopic tumor‐bearing mice shows highly efficient tumor retention and significantly enhanced PA contrast. Tumor tissue ≈1.5 mm below the skull can still be clearly visualized in vivo. Previous studies suggest that the fabricated S‐MoS2 with amplified PA effect have high potential to serve as an efficient nanoplatform for sensitive PA molecular imaging and hold promising prospect for translational medicine. 相似文献
2.
Phototransistors with Negative or Ambipolar Photoresponse Based on As‐Grown Heterostructures of Single‐Walled Carbon Nanotube and MoS2
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Van Tu Nguyen Woongbin Yim Sae June Park Byung Hee Son Young Chul Kim Thi Thanh Cao Yumin Sim Yoon‐Jong Moon Van Chuc Nguyen Maeng‐Je Seong Sun‐Kyung Kim Yeong Hwan Ahn Soonil Lee Ji‐Yong Park 《Advanced functional materials》2018,28(40)
A facile synthesis method for the heterostructures of single‐walled carbon nanotubes (SWCNTs) and few‐layer MoS2 is reported. The heterostructures are realized by in situ chemical vapor deposition of MoS2 on individual SWCNTs. Field effect transistors based on the heterostructures display different transfer characteristics depending on the formation of MoS2 conduction channels along SWCNTs. Under light illumination, negative photoresponse originating from charge transfer from MoS2 to SWCNT is observed while positive photoresponse is observed in MoS2 conduction channels, leading to ambipolar photoresponse in devices with both SWCNT and MoS2 channels. The heterostructure phototransistor, for negative photoresponse, exhibits high responsivity (100–1000 AW?1) at low bias voltages (0.1 V) in the visible spectrum (500–700 nm) by combining high mobility conduction channel (SWCNT) with efficient light absorber (MoS2). 相似文献
3.
Ultraviolet‐Light‐Induced Reversible and Stable Carrier Modulation in MoS2 Field‐Effect Transistors
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Arun Kumar Singh Shaista Andleeb Jai Singh Hoang Tien Dung Yongho Seo Jonghwa Eom 《Advanced functional materials》2014,24(45):7125-7132
The tuning of charge carrier concentrations in semiconductor is necessary in order to approach high performance of the electronic and optoelectronic devices. It is demonstrated that the charge‐carrier density of single‐layer (SL), bilayer (BL), and few‐layer (FL) MoS2 nanosheets can be finely and reversibly tuned with N2 and O2 gas in the presence of deep‐ultraviolet (DUV) light. After exposure to N2 gas in the presence of DUV light, the threshold voltages of SL, BL, and FL MoS2 field‐effect transistors (FETs) shift towards negative gate voltages. The exposure to N2 gas in the presence of DUV light notably improves the drain‐to‐source current, carrier density, and charge‐carrier mobility for SL, BL, and FL MoS2 FETs. Subsequently, the same devices are exposed to O2 gas in the presence of DUV light for different periods and the electrical characteristics are completely recovered after a certain time. The doping by using the combination of N2 and O2 gas with DUV light provides a stable, effective, and facile approach for improving the performance of MoS2 electronic devices. 相似文献
4.
Three‐Dimensional Structures of MoS2 Nanosheets with Ultrahigh Hydrogen Evolution Reaction in Water Reduction
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Xiumei Geng Wei Wu Ning Li Weiwei Sun Johnathan Armstrong Alaa Al‐hilo Matthew Brozak Jingbiao Cui Tar‐pin Chen 《Advanced functional materials》2014,24(39):6123-6129
The hydrogen evolution reaction in an alkaline environment using a non‐precious catalyst with much greater efficiency represents a critical challenge in research. Here, a robust and highly active system for hydrogen evolution reaction in alkaline solution is reported by developing MoS2 nanosheet arrays vertically aligned on graphene‐mediated 3D Ni networks. The catalytic activity of the 3D MoS2 nanostructures is found to increase by 2 orders of magnitude as compared to the Ni networks without MoS2. The MoS2 nanosheets vertically grow on the surface of graphene by employing tetrakis(diethylaminodithiocarbomato)molybdate(IV) as the molybdenum and sulfur source in a chemical vapor deposition process. The few‐layer MoS2 nanosheets on 3D graphene/nickel structure can maximize the exposure of their edge sites at the atomic scale and present a superior catalysis activity for hydrogen production. In addition, the backbone structure facilitates as an excellent electrode for charge transport. This precious‐metal‐free and highly efficient active system enables prospective opportunities for using alkaline solution in industrial applications. 相似文献
5.
Nonvolatile Floating‐Gate Memories Based on Stacked Black Phosphorus–Boron Nitride–MoS2 Heterostructures
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Dong Li Xiaojuan Wang Qichong Zhang Liping Zou Xiangfan Xu Zengxing Zhang 《Advanced functional materials》2015,25(47):7360-7365
Research on van der Waals heterostructures based on stacked 2D atomic crystals is intense due to their prominent properties and potential applications for flexible transparent electronics and optoelectronics. Here, nonvolatile memory devices based on floating‐gate field‐effect transistors that are stacked with 2D materials are reported, where few‐layer black phosphorus acts as channel layer, hexagonal boron nitride as tunnel barrier layer, and MoS2 as charge trapping layer. Because of the ambipolar behavior of black phosphorus, electrons and holes can be stored in the MoS2 charge trapping layer. The heterostructures exhibit remarkable erase/program ratio and endurance performance, and can be developed for high‐performance type‐switching memories and reconfigurable inverter logic circuits, indicating that it is promising for application in memory devices completely based on 2D atomic crystals. 相似文献
6.
Michael Saliba Wei Zhang Victor M. Burlakov Samuel D. Stranks Yao Sun James M. Ball Michael B. Johnston Alain Goriely Ulrich Wiesner Henry J. Snaith 《Advanced functional materials》2015,25(31):5038-5046
Organic–inorganic metal halide perovskite solar cells have emerged in the past few years to promise highly efficient photovoltaic devices at low costs. Here, temperature‐sensitive core–shell Ag@TiO2 nanoparticles are successfully incorporated into perovskite solar cells through a low‐temperature processing route, boosting the measured device efficiencies up to 16.3%. Experimental evidence is shown and a theoretical model is developed which predicts that the presence of highly polarizable nanoparticles enhances the radiative decay of excitons and increases the reabsorption of emitted radiation, representing a novel photon recycling scheme. The work elucidates the complicated subtle interactions between light and matter in plasmonic photovoltaic composites. Photonic and plasmonic schemes such as this may help to move highly efficient perovskite solar cells closer to the theoretical limiting efficiencies. 相似文献
7.
6‐Mercaptopurine‐Induced Fluorescence Quenching of Monolayer MoS2 Nanodots: Applications to Glutathione Sensing,Cellular Imaging,and Glutathione‐Stimulated Drug Delivery
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Shih‐Chiang Chen Chang‐Yu Lin Tian‐Lu Cheng Wei‐Lung Tseng 《Advanced functional materials》2017,27(41)
Molybdenum disulfide (MoS2) nanodots (NDs) with sulfur vacancies have been demonstrated to be suitable to conjugate thiolated molecules. However, thiol‐induced fluorescence quenching of MoS2 NDs has been rarely explored. In this study, 6‐mercaptopurine (6‐MP) serves as an efficient quencher for the fluorescence of monolayer MoS2 (M‐MoS2) NDs. 6‐MP molecules are chemically adsorbed at the sulfur vacancy sites of the M‐MoS2 NDs. The formed complexes trigger the efficient fluorescence quenching of the M‐MoS2 NDs due to acceptor‐excited photoinduced electron transfer. The presence of glutathione (GSH) efficiently triggers the release of 6‐MP from the M‐MoS2 NDs, thereby switching on the fluorescence of the M‐MoS2 NDs. Thus, the 6‐MP‐M‐MoS2 NDs are implemented as a platform for the sensitive and selective detection of GSH in erythrocytes and live cells. Additionally, thiolated doxorubicin (DOX‐SH)‐loaded M‐MoS2 NDs (DOX‐SH/M‐MoS2 NDs) serve as GSH‐responsive nanocarriers for DOX‐SH delivery. In vitro studies reveal that the DOX‐SH/M‐MoS2 NDs exhibit efficient uptake by HeLa cells and greater cytotoxicity than free DOX‐SH and DOX. In vivo study shows that GSH is capable of triggering the release of DOX‐SH from M‐MoS2 ND‐based nanomaterials in mice. It is revealed that the DOX‐SH/M‐MoS2 NDs can be implemented for simultaneous drug delivery and fluorescence imaging. 相似文献
8.
《Advanced functional materials》2018,28(35)
The recent discoveries of transition‐metal dichalcogenides (TMDs) as novel 2D electronic materials hold great promise to a rich variety of artificial van der Waals (vdWs) heterojunctions and superlattices. Moreover, most of the monolayer TMDs become intrinsically piezoelectric due to the lack of structural centrosymmetry, which offers them a new degree of freedom to interact with external mechanical stimuli. Here, fabrication of flexible vdWs p–n diode by vertically stacking monolayer n‐MoS2 and a few‐layer p‐WSe2 is achieved. Electrical measurement of the junction reveals excellent current rectification behavior with an ideality factor of 1.68 and photovoltaic response is realized. Performance modulation of the photodiode via piezo‐phototronic effect is also demonstrated. The optimized photoresponsivity increases by 86% when introducing a −0.62% compressive strain along MoS2 armchair direction, which originates from realigned energy‐band profile at MoS2/WSe2 interface under strain‐induced piezoelectric polarization charges. This new coupling mode among piezoelectricity, semiconducting, and optical properties in 2D materials provides a new route to strain‐tunable vdWs heterojunctions and may enable the development of novel ultrathin optoelectronics. 相似文献
9.
Virendra V. Singh Kevin Kaufmann Berta Esteban‐Fernández de Ávila Emil Karshalev Joseph Wang 《Advanced functional materials》2016,26(34):6270-6278
2D molybdenum disulfide (MoS2) is herein explored as an advanced surface material in the fabrication of powerful tubular microengines. The new catalytic self‐propelled open‐tube bilayer microengines have been fabricated using a template electrodeposition and couple the unique properties of sp2 hybridized MoS2 with highly reactive inner granular Pt catalytic structures. The MoS2/metal microengines display extremely efficient bubble propulsion, reflecting the granular structure of the inner catalytic platinum or gold layers (compared to the smooth metal surfaces of common micromotors). The efficient movement of functionalized MoS2 micromotors can address challenges imposed by slow mass transport processes involved in various applications of MoS2. The delocalized electron network of the MoS2 outer layer facilitates π–π stacking interactions and endows the tubular microengines with a diverse array of capabilities. These are demonstrated here for efficient loading and release of the drug doxorubicin, and rapid and sensitive “OFF–ON” fluorescent detection of important nucleic acids (miRNA‐21) and proteins (thrombin) using microengines modified with dye‐labeled single‐stranded DNA and aptamer, respectively. Such coupling of the attractive capabilities of 2D‐MoS2 nanosheets with rapidly moving microengines provides an opportunity to develop multifunctional micromachines for diverse biomedical applications ranging from efficient drug delivery to the detection of important bioanalytes. 相似文献
10.
Dependence of Photocurrent Enhancements in Quantum Dot (QD)‐Sensitized MoS2 Devices on MoS2 Film Properties
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John J. Gough Niall McEvoy Maria O'Brien Alan P. Bell David McCloskey John B. Boland Jonathan N. Coleman Georg S. Duesberg A. Louise Bradley 《Advanced functional materials》2018,28(13)
This report demonstrates highly efficient nonradiative energy transfer (NRET) from alloyed CdSeS/ZnS semiconductor nanocrystal quantum dots (QDs) to MoS2 films of varying layer thicknesses, including pristine monolayers, mixed monolayer/bilayer, polycrystalline bilayers, and bulk‐like thicknesses, with NRET efficiencies of over 90%. Large‐area MoS2 films are grown on Si/SiO2 substrates by chemical vapor deposition. Despite the ultrahigh NRET efficiencies there is no distinct increase in the MoS2 photoluminescence intensity. However, by studying the optoelectronic properties of the MoS2 devices before and after adding the QD sensitizing layer photocurrent enhancements as large as ≈14‐fold for pristine monolayer devices are observed, with enhancements on the order of ≈2‐fold for MoS2 devices of mixed monolayer and bilayer thicknesses. For the polycrystalline bilayer and bulk‐like MoS2 devices there is almost no increase in the photocurrent after adding the QDs. Industrially scalable techniques are specifically utilized to fabricate the samples studied in this report, demonstrating the viability of this hybrid structure for commercial photodetector or light harvesting applications. 相似文献
11.
Novel and Enhanced Optoelectronic Performances of Multilayer MoS2–WS2 Heterostructure Transistors
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Nengjie Huo Jun Kang Zhongming Wei Shu‐Shen Li Jingbo Li Su‐Huai Wei 《Advanced functional materials》2014,24(44):7025-7031
Van der Waals heterostructures designed by assembling isolated two‐dimensional (2D) crystals have emerged as a new class of artificial materials with interesting and unusual physical properties. Here, the multilayer MoS2–WS2 heterostructures with different configurations are reported and their optoelectronic properties are studied. It is shown that the new heterostructured material possesses new functionalities and superior electrical and optoelectronic properties that far exceed the one for their constituents, MoS2 or WS2. The vertical transistor exhibits a novel rectifying and bipolar behavior, and can also act as photovoltaic cell and self‐driven photodetector with photo‐switching ratio exceeding 103. The planar device also exhibits high field‐effect ON/OFF ratio (>105), high electron mobility of 65 cm2/Vs, and high photoresponsivity of 1.42 A/W compared to that in isolated multilayer MoS2 or WS2 nanoflake transistors. The results suggest that formation of MoS2–WS2 heterostructures could significantly enhance the performance of optoelectronic devices, thus open up possibilities for future nanoelectronic, photovoltaic, and optoelectronic applications. 相似文献
12.
Surface‐Shielding Nanostructures Derived from Self‐Assembled Block Copolymers Enable Reliable Plasma Doping for Few‐Layer Transition Metal Dichalcogenides
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Soonmin Yim Dong Min Sim Woon Ik Park Min‐Jae Choi Jaesuk Choi Jaebeom Jeon Kwang Ho Kim Yeon Sik Jung 《Advanced functional materials》2016,26(31):5631-5640
Precise modulation of electrical and optical properties of 2D transition metal dichalcogenides (TMDs) is required for their application to high‐performance devices. Although conventional plasma‐based doping methods have provided excellent controllability and reproducibility for bulk or relatively thick TMDs, the application of plasma doping for ultrathin few‐layer TMDs has been hindered by serious degradation of their properties. Herein, a reliable and universal doping route is reported for few‐layer TMDs by employing surface‐shielding nanostructures during a plasma‐doping process. It is shown that the surface‐protection oxidized polydimethylsiloxane nanostructures obtained from the sub‐20 nm self‐assembly of Si‐containing block copolymers can preserve the integrity of 2D TMDs and maintain high mobility while affording extensive control over the doping level. For example, the self‐assembled nanostructures form periodically arranged plasma‐blocking and plasma‐accepting nanoscale regions for realizing modulated plasma doping on few‐layer MoS2, controlling the n‐doping level of few‐layer MoS2 from 1.9 × 1011 cm?2 to 8.1 × 1011 cm?2 via the local generation of extra sulfur vacancies without compromising the carrier mobility. 相似文献
13.
Xiangming Xu Chenhui Zhang Mrinal K. Hota Zhixiong Liu Xixiang Zhang Husam N. Alshareef 《Advanced functional materials》2020,30(11)
Wafer‐scale, single‐crystalline 2D semiconductors without grain boundaries and defects are needed for developing reliable next‐generation integrated 2D electronics. Unfortunately, few literature reports exist on the growth of 2D semiconductors with single‐crystalline structure at the wafer scale. It is shown that direct sulfurization of as‐deposited epitaxial MoO2 films (especially, with thicknesses more than ≈5 nm) produces textured MoS2 films. This texture is inherited from the high density of defects present in the as‐prepared epitaxial MoO2 film. In order to eliminate the texture of the converted MoS2 films, a new capping layer annealing process (CLAP) is introduced to improve the crystalline quality of as‐deposited MoO2 films and minimize its defects. It is demonstrated that sulfurization of the CLAP‐treated MoO2 films leads to the formation of single‐crystalline MoS2 films, instead of textured films. It is shown that the single‐crystalline MoS2 films exhibit field‐effect mobility of 6.3 cm2 V?1 s?1, which is 15 times higher than that of textured MoS2. These results can be attributed to the smaller concentration of defects in the single‐crystalline films. 相似文献
14.
Yipeng An Yusheng Hou Kun Wang Shijing Gong Chunlan Ma Chuanxi Zhao Tianxing Wang Zhaoyong Jiao Heyan Wang Ruqian Wu 《Advanced functional materials》2020,30(32)
The intrinsic spin‐dependent transport properties of two types of lateral VS2|MoS2 heterojunctions are systematically investigated using first‐principles calculations, and their various nanodevices with novel properties are designed. The lateral VS2|MoS2 heterojunction diodes show a perfect rectifying effect and are promising for the applications of Schottky diodes. A large spin‐polarization ratio is observed for the A‐type device and pure spin‐mediated current is then realized. The gate voltage significantly tunes the current and rectification ratio of their field‐effect transistors. In addition, they all demonstrate a sensitive photoresponse to blue light, and could be used as photodetector and photovoltaic device. Moreover, they generate an effective thermally driven current when a temperature gratitude appears between the two terminals, suggesting them as potential thermoelectric materials. Hence, the lateral VS2|MoS2 heterojunctions show a multifunctional nature and have various potential applications in spintronics, optoelectronics, and spin caloritronics. 相似文献
15.
Ying Yu Ziheng Ji Shuai Zu Bowen Du Yimin Kang Ziwei Li Zhangkai Zhou Kebin Shi Zheyu Fang 《Advanced functional materials》2016,26(35):6394-6401
2D transition metal dichalcogenides are becoming attractive materials for novel photoelectric and photovoltaic applications due to their excellent optoelectric properties and accessible optical bandgap in the near‐infrared to visible range. Devices utilizing 2D materials integrated with metal nanostructures have recently emerged as efficient schemes for hot electron‐based photodetection. Metal‐semiconductor heterostructures with low cost, simple procedure, and fast response time are crucial for the practical applications of optoelectric devices. In this paper, template‐based sputtering method is used first to fabricate Au nanoantenna (NA)/MoS2 heterostructures with low cost, simple preparation, broad spectral response, and fast response time. Through the measurement of femtosecond pump‐probe spectroscopy, it is demonstrated that plasmon‐induced hot electron transfer takes place in the Au NA/MoS2 heterostructure on the order of 200 fs with an injected electron density of about 5.6 × 1012 cm?2. Moreover, the pump‐power‐dependent photoluminescence spectra confirm that the exciton energy of MoS2 can be enhanced, coupled, and reradiated by the Au NA. Such ultrafast plasmon‐induced hot electron transfer in the metal‐semiconductor heterostructure can enable novel 2D devices for light harvesting and photoelectric conversion. 相似文献
16.
Two‐dimensional inorganic materials are emerging as a premiere class of materials for fabricating modern electronic devices. The interest in 2D layered transition metal dichalcogenides is especially high. Particularly, 2D MoS2 is being heavily researched due to its novel functionalities and its suitability for a wide range of electronic and optoelectronic applications. In this article, the progress in mono/few layer(s) MoS2 research is reviewed by focusing primarily on the layer dependent evolution of crystal, phonon, and electronic structure. The review includes extensive detail into the methodologies adapted for single or few layer(s) MoS2 growth. Further, the review covers the versatility of 2D MoS2 for a broad range of device applications. Recent advancements in the field of van der Waals heterostructures are also highlighted at the end of the review. 相似文献
17.
Tuning the Excitonic States in MoS2/Graphene van der Waals Heterostructures via Electrochemical Gating
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Yang Li Cheng‐Yan Xu Jing‐Kai Qin Wei Feng Jia‐Ying Wang Siqi Zhang Lai‐Peng Ma Jian Cao Ping An Hu Wencai Ren Liang Zhen 《Advanced functional materials》2016,26(2):293-302
The behavior of excitons in van der Waals (vdWs) heterostructures depends on electron–electron interactions and charge transfer at the hetero‐interface. However, what still remains to be unraveled is to which extent the carrier densities of both counterparts and the band alignment in the vdWs heterostructures determine the photoluminescence properties. Here, we systematically study the photoluminescence properties of monolayer MoS2/graphene heterostructures by modulating the carrier densities and contact barrier at the interface via electrochemical gating. It is shown that the PL intensities of excitons can be tuned by more than two orders of magnitude, and a blue‐shift of the exciton peak of up to 40 meV is observed. By extracting the carrier density of MoS2 using an electric potential distribution model, and the Schottky barrier using first‐principle calculations, we find that the controllable carrier density in MoS2 plays a dominant role in the PL tuning at negative gate bias, whereas the interlayer relaxation of excitons induced by the Schottky barrier has a major contribution at positive gate bias. This is further verified by controlling the tunneling barrier and screening field across MoS2 by inserting self‐assembled monolayers (SAMs) at the interface. These findings will benefit to better understand the effect of many‐body interactions and hetero‐interfaces on the optical and optoelectronic properties in vdWs heterostructures. 相似文献
18.
Jianping Shi Yang Yang Yu Zhang Donglin Ma Wei Wei Qingqing Ji Yanshuo Zhang Xiuju Song Teng Gao Cong Li Xinhe Bao Zhongfan Liu Qiang Fu Yanfeng Zhang 《Advanced functional materials》2015,25(6):842-849
Controllable synthesis of large domain, high‐quality monolayer MoS2 is the basic premise both for exploring some fundamental physical issues, and for engineering its applications in nanoelectronics, optoelectronics, etc. Herein, by introducing H2 as carrier gas, the successful synthesis of large domain monolayer MoS2 triangular flakes on Au foils, with the edge length approaching to 80 mm is reported. The growth process is proposed to be mediated by two competitive effects with H2 acting as both a reduction promoter for efficient sulfurization of MoO3 and an etching reagent of resulting MoS2 flakes. By using low‐energy electron microscopy/diffraction, the crystal orientations and domain boundaries of MoS2 flakes directly on Au foils for the first time are further identified. These on‐site and transfer‐free characterizations should shed light on the initial growth and the aggregation of MoS2 on arbitrary substrates, further guiding the growth toward large domain flakes or monolayer films. 相似文献
19.
Fluorescent Block Copolymer‐MoS2 Nanocomposites for Real‐Time Photothermal Heating and Imaging
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Chan Ho Park Hongseok Yun Hyunseung Yang Junhyuk Lee Bumjoon J. Kim 《Advanced functional materials》2017,27(5)
Novel self‐monitoring photothermal (PT) agents are developed using optothermally responsive block copolymer‐MoS2 composites (BCP‐MoS2), which enable simultaneous PT heating and imaging of temperature profiles. In particular, upon near‐infrared light exposure, PT energy from MoS2 successfully increases local temperature and induces thermally activated conformational transitions of the BCP on MoS2. This leads to fluorescent signal changes caused by distance‐dependent Förster resonance energy transfer between the BCP and MoS2. Importantly, it is demonstrated that the use of BCP‐MoS2 for PT heating and optical mapping is fully reversible with excellent stability. The detailed mechanism of the responsive behavior of BCP‐MoS2 is elucidated by measurements of time‐resolved fluorescence and dynamic light scattering. In addition, the BCP‐MoS2 system is integrated into organogel matrices to demonstrate its potential as aportable, self‐monitoring PT system suitable for biological and environmental applications. 相似文献
20.
Yagang Yao Lorenzo Tolentino Zhongzheng Yang Xiaojuan Song Wen Zhang Yongsheng Chen Ching‐ping Wong 《Advanced functional materials》2013,23(28):3577-3583
Molybdenum disulfide (MoS2) nanosheets have been attracting increasing research interests due to their unique material properties. However, the lack of a reliable large‐scale production method impedes their practical applications. Here a facile, efficient, and scalable method for the fabrication of high‐concentration aqueous dispersion of MoS2 nanosheets using combined grinding and sonication is reported. The 26.7 ± 0.7 mg/mL concentration achieved is the highest concentration in an aqueous solution reported up to now. Grinding generates pure shear forces to detach the MoS2 layers from the bulk materials. Subsequent sonication further breaks larger crystallites into smaller crystallites, which promotes the dispersion of MoS2 nanosheets in ethanol/water solutions. The exfoliation process establishes a new paradigm in the top‐down fabrication of 2D nanosheets in aqueous solution. In the meantime, MoS2‐based sensing film produced using this approach has successfully demonstrated the feasibility of a low‐cost and efficient NH3 gas sensor using inkjet printing as a viable method. 相似文献