Query: Ultrasensitive photodetectors based on monolayer MoS2

Candidate papers:

abstract: Two dimensional materials are an emerging class of new materials with a wide range of electrical properties and potential practical applications. Although graphene is the most well studied two dimensional material, single layers of other materials, such as insulating BN (ref. 2) and semiconducting MoS2 (refs 3, 4) or WSe2 (refs 5, 6) are gaining increasing attention as promising gate insulators and channel materials for field effect transistors. Because monolayer MoS2 is a direct bandgap semiconductor due to quantum mechanical confinement, it could be suitable for applications in optoelectronic devices where the direct bandgap would allow a high absorption coefficient and efficient electron hole pair generation under photoexcitation. Here, we demonstrate ultrasensitive monolayer MoS2 phototransistors with improved device mobility and ON current. Our devices show a maximum external photoresponsivity of 880 A W( 1) at a wavelength of 561 nm and a photoresponse in the 400 680 nm range. With recent developments in large scale production techniques such as liquid scale exfoliation and chemical vapour deposition like growth, MoS2 shows important potential for applications in MoS2 based integrated optoelectronic circuits, light sensing, biomedical imaging, video recording and spectroscopy.
author_names: Oriol Lopez-Sanchez

Dominik S Lembke

M Kayci

Aleksandra Radenovic

Andras Kis
title: Ultrasensitive photodetectors based on monolayer MoS2.
venue: Nature nanotechnology
year: 2013

abstract: We studied the influence of different pre deposition surface treatments and contact materials on the photoresponse decay. We find that different surface cleaning treatments can be used to reduce the decay time. This can be explained by differences in resulting level of hydrophobicity of the functionalized SiO
author_names: Oriol Lopez-Sanchez

Dominik S Lembke

M Kayci

Aleksandra Radenovic

Andras Kis
title: Supplementary information for Ultrasensitive photodetectors based on monolayer MoS2
year: 2013

abstract: 2D transition metal dichalcogenide (2D TMD) materials and their van der Waals heterostructures (vdWHs) have inspired worldwide efforts in the fields of electronics and optoelectronics. However, photodetectors based on 2D/2D vdWHs suffer from performance limitations due to the weak optical absorption of their atomically thin nature. In this work, taking advantage of an excellent light absorption coefficient, low temperature solution processability, and long charge carrier diffusion length, all inorganic halides perovskite CsPbI3 x Br x quantum dots are integrated with monolayer MoS2 for high performance and low cost photodetectors. A favorable energy band alignment facilitating interfacial photocarrier separation and efficient carrier injection into the MoS2 layer inside the 0D 2D mixed dimensional vdWHs are confirmed by a series of optical characterizations. Owing to the synergistic effect of the photogating mechanism and the modulation of Schottky barriers, the corresponding phototransistor exhibits a high photoresponsivity of 7.7 x 104 A W 1, a specific detectivity of 5.6 x 1011 Jones, and an external quantum efficiency exceeding 107% The demonstration of such 0D 2D mixed dimensional heterostructures proposed here would open up a wide realm of opportunities for designing low cost, flexible transparent, and high performance optoelectronics.
author_names: Hualin Wu

Haonan Si

Zihan Zhang

Zhuo Kang

Pingwei Wu

Lixin Zhou

Suicai Zhang

Zheng Zhang

Qingliang Liao

Yue Zhang
title: All Inorganic Perovskite Quantum Dot Monolayer MoS2 Mixed Dimensional van der Waals Heterostructure for Ultrasensitive Photodetector
venue: Advanced science
year: 2018

abstract: Abstract Photodetectors (PD) with high detectivity, high quantum efficiency and fast response are fundamental units to achieve sensors, imagers, and many others functional optoelectronics. Here we demonstrate high performance vertical stacked 2D MoS2/CuPc heterojunction based photodetectors with high sensitivity, high external quantum efficiency and ultrafast response time. The functional p type organic thin film of CuPc was thermally evaporated on n type two dimension (2D) MoS2 monolayer to create an ideal type II heterojunction interface, where ultrafast charge transfer (CT) occur in 16 ps, followed by effective exciton separation and charge collection. As a result, photoresponse time as fast as 436 ms has been obtained for 2D MoS2/CuPc PDs, as well as a profound responsivity of 3.0 x 10 3 A/W and a detectivity of 2.0 x 1010 Jones with a peak external quantum efficiency (EQE) of 483% This work suggests a feasible route to develop ultrasensitive visible light photodetector by 2D materials.
author_names: Z -H Xu

L L Tang

S W Zhang

J Z Li

B L Liu

S C Zhao
title: 2D MoS2/CuPc heterojunction based highly sensitive photodetectors through ultrafast charge transfer
year: 2020

abstract: Two dimensional (2D) materials are a new type of materials under intense study because of their interesting physical properties and wide range of potential applications from nanoelectronics to sensing and photonics. Monolayers of semiconducting transition metal dichalcogenides MoS2 or WSe2 have been proposed as promising channel materials for field effect transistors. Their high mechanical flexibility, stability, and quality coupled with potentially inexpensive production methods offer potential advantages compared to organic and crystalline bulk semiconductors. Due to quantum mechanical confinement, the band gap in monolayer MoS2 is direct in nature, leading to a strong interaction with light that can be exploited for building phototransistors and ultrasensitive photodetectors. Here, we report on the realization of light emitting diodes based on vertical heterojunctions composed of n type monolayer MoS2 and p type silicon. Careful interface engineering allows us to realize diodes showing rectification and light emission from the entire surface of the heterojunction. Electroluminescence spectra show clear signs of direct excitons related to the optical transitions between the conduction and valence bands. Our p n diodes can also operate as solar cells, with typical external quantum efficiency exceeding 4% Our work opens up the way to more sophisticated optoelectronic devices such as lasers and heterostructure solar cells based on hybrids of 2D semiconductors and silicon.
author_names: Oriol Lopez-Sanchez

Esther Alarcon Llado

Volodymyr B Koman

Anna Fontcuberta i Morral

Aleksandra Radenovic

Andras Kis
title: Light Generation and Harvesting in a van der Waals Heterostructure
venue: ACS nano
year: 2014

abstract: Two dimensional (2D) transition metal dichalcogenides (TMDs) have been receiving tremendous attention because of their outstanding performance as nanoscale devices. Monolayer molybdenum disulfide (MoS2) is a very promising candidate for applications such as field effect transistors, chemical sensors and ultrasensitive photodetectors due to its adjustable direct band gap. It is known that structural defects, which can not be avoided during the fabrication of the material, influence drastically its optical and electronic properties[1,2] Most of the defects are due to a lack of Sulfur atoms (S defect) which have been identified as a primary reason for the observed low performance of MoS2 based photoelectric devices. However, the S defect can also be used in a positive manner, for example, to promote the hydrogen evolution reaction[3] and to vary the properties of the material for the adsorption of molecules[4] by changing the coordination number of Mo atoms.
author_names: K Wang

Beate Paulus
title: First principle investigation of functionalized transition metal dichalcogenides
year: 2019

abstract: Monolayer MoS2, a direct bandgap transition metal dichalcogenide (TMD) has attracted worldwide attention in electronics and optoelectronics. However, the performance of photodetectors based on monolayer MoS2 is restricted to a weak optical absorption, narrow absorption range, and persistent photoconductance. Herein, benefiting from an easy solution process, high light absorption coefficient, and wide absorption range, environment friendly CuInSe2 quantum dots (QDs) are hybridized with monolayer MoS2 for high performance broadband photodetectors. Owing to the favorable type II energy band alignment of MoS2/CuInSe2 QDs, the hybrid photodetector exhibits a broadband photoresponse from the ultraviolet to near infrared region, with an ultrahigh photoresponsivity of 74.8 A/W at 1064 nm, and compared with those of the pristine MoS2 device, the photoresponsivity and specific detectivity in the ultraviolet visible region were enhanced by about 30 and 20 times, respectively. Furthermore, the formed depletion region at the MoS2/CuInSe2 QDs interface can significantly increase the photoresponse speed, and the accumulated holes in the QD side induce a strong photogating effect to improve the photoresponsive characteristics of the hybrid photodetector. Our work opens up opportunities for fabricating high performance monolayer TMD based broadband photodetectors.
author_names: Tao Shen

Feng Li

Zhenyun Zhang

Lei Xu

Junjie Qi
title: High Performance Broadband Photodetector Based on Monolayer MoS2 Hybridized with Environment Friendly CuInSe2 Quantum Dots.
venue: ACS applied materials interfaces
year: 2020

abstract: Field effect transistor (FET) biosensors based on low dimensional materials present the advantages of low cost, high speed, small size, and excellent compatibility with integrated circuits (ICs) In this work, we fabricated highly sensitive FET based DNA biosensors based on chemical vapor deposition (CVD) grown monolayer MoS2 films in batches and explored their application in noninvasive prenatal testing (NIPT) for trisomy 21 syndrome. Specifically, MoS2 was functionalized with gold nanoparticles (Au NPs) of an optimized size and at an ideal density, and then, probe DNAs for the specific capture of target DNAs were immobilized on the nanoparticles. The fabricated FET biosensors are able to reliably detect target DNA fragments (chromosome 21 or 13) with a detection limit below 100 aM, a high response up to 240% and a high specificity, which satisfy the requirement for the screening of Down syndrome. In addition, a real time test was conducted to show that the biosensor clearly responds to the target DNA at concentrations as low as 1 fM. Our approach shows the potential for detecting the over expression of chromosome 21 in the peripheral blood of pregnant women and achieving Down syndrome screening.
author_names: Jingxia Liu

Xihua Chen

Qinqin Wang

Mengmeng Xiao

Donglai Zhong

Wei Sun

Guangyu Zhang

Zhiyong Zhang
title: Ultrasensitive Monolayer MoS2 Field Effect Transistor Based DNA Sensors for Screening of Down Syndrome.
venue: Nano letters
year: 2019

abstract: Abstract Two dimensional layers of metal dichalcogenides have attracted much attention because of their ultrathin thickness and potential applications in electronics and optoelectronics. In this regard, we further explore the optoelectronic properties of monolayer MoS2 synthesized by chemical vapor deposition on sapphire substrate and contacted the Au electrode by lithographie method for applications in photodetectors. The device exhibits broadband photoresponse (UV Vis NIR) a lower subthreshold swing (0.5 V) higher detectivity (1010 Jones) and superior responsivity (0.0084 A/W) We believe that this work provides important scientific insights for photoelectric response properties of emerging atomically layered 2D materials for optoelectronic applications.
author_names: Yong Heng Zhou

Heishoku An

Cheng Gao

Zhaoqiang Zheng

Bing Wang
title: UV Vis NIR photodetector based on monolayer MoS2
venue: Materials Letters
year: 2019

author_names: Louwen Zhang

Shaoli Shen

Man Li

Luying Li

Jibin Zhang

Lianwei Fan

Feng Cheng

Chen Li

Mengqin Zhu

Zhe Kang

Jun Su

Tianyou Zhai

Yihua Gao
title: Strategies for Air Stable and Tunable Monolayer MoS 2 Based Hybrid Photodetectors with High Performance by Regulating the Fully Inorganic Trihalide Perovskite Nanocrystals
venue: Advanced Optical Materials
year: 2019