Atomically thin transition metal dichalcogenides have emerged as promising candidates for sensitive photodetection. Here, we report a photoconductivity study of biased mono- and bilayer molybdenum disulfide field-effect transistors. We identify photovoltaic and photoconductive effects, which both show strong photogain. The photovoltaic effect is described as a shift in transistor threshold voltage due to charge transfer from the channel to nearby molecules, including SiO2 surface-bound water. The photoconductive effect is attributed to the trapping of carriers in band tail states in the molybdenum disulfide itself. A simple model is presented that reproduces our experimental observations, such as the dependence on incident optical power and gate voltage. Our findings offer design and engineering strategies for atomically thin molybdenum disulfide photodetectors, and we anticipate that the results are generalizable to other transition metal dichalcogenides as well.

Mechanisms of photoconductivity in atomically thin MoS2

Tunable smart mid infrared thermal control emitter based on phase change material VO2 thin film

This paper introduces a novel metamaterial absorber based on surface plasmon resonance (SPR). The absorber is capable of triple-mode perfect absorption, polarization independence, incident angle insensitivity, tunability, high sensitivity, and a high figure of merit (FOM). The structure of the absorber consists of a sandwiched stack: a top layer of single-layer graphene array with an open-ended prohibited sign type (OPST) pattern, a middle layer of thicker SiO2, and a bottom layer of the gold metal mirror (Au). The simulation of COMSOL software suggests it achieves perfect absorption at frequencies of fI = 4.04 THz, fII = 6.76 THz, and fIII = 9.40 THz, with absorption peaks of 99.404%, 99.353%, and 99.146%, respectively. These three resonant frequencies and corresponding absorption rates can be regulated by controlling the patterned graphene’s geometric parameters or just adjusting the Fermi level (EF). Additionally, when the incident angle changes between 0~50°, the absorption peaks still reach 99% regardless of the kind of polarization. Finally, to test its refractive index sensing performance, this paper calculates the results of the structure under different environments which demonstrate maximum sensitivities in three modes: SI = 0.875 THz/RIU, SII = 1.250 THz/RIU, and SIII = 2.000 THz/RIU. The FOM can reach FOMI = 3.74 RIU−1, FOMII = 6.08 RIU−1, and FOMIII = 9.58 RIU−1. In conclusion, we provide a new approach for designing a tunable multi-band SPR metamaterial absorber with potential applications in photodetectors, active optoelectronic devices, and chemical sensors.

/pdf/triple-band-surface-plasmon-resonance-metamaterial-absorber-291s0snm.pdf

Triple-Band Surface Plasmon Resonance Metamaterial Absorber Based on Open-Ended Prohibited Sign Type Monolayer Graphene

Layered black phosphorus (BP), a promising 2D material, tends to oxidize under ambient conditions While such defective BP is typically considered undesirable, defect engineering has in fact been exploited in contemporary materials to create new behaviors and functionalities In this spirit, new opportunities arising from intrinsic defect states in BP, particularly through harnessing unique photoresponse characteristics, and demonstrating three distinct optoelectronic applications are demonstrated First, the ability to distinguish between UV-A and UV-B radiations using a single material that has tremendous implications for skin health management is shown Second, the same device is utilized to show an optically stimulated mimicry of synaptic behavior opening new possibilities in neuromorphic computing Third, it is shown that serially connected devices can be used to perform digital logic operations using light The underpinning photoresponse is further translated on flexible substrates, highlighting the viability of the technology for mechanically conformable and wearable systems This demonstration paves the way toward utilizing the unexplored potential offered by defect engineering of 2D materials for applications spanning across a broad range of disciplines

Multifunctional Optoelectronics via Harnessing Defects in Layered Black Phosphorus

Ternary two-dimensional (2D) semiconductors with controllable wide bandgap, high ultraviolet (UV) absorption coefficient, and critical tuning freedom degree of stoichiometry variation have a great application prospect for UV detection. However, as-reported ternary 2D semiconductors often possess a bandgap below 3.0 eV, which must be further enlarged to achieve comprehensively improved UV, especially deep-UV (DUV), detection capacity. Herein, sub-one-unit-cell 2D monolayer BiOBr nanoflakes (≈0.57 nm) with a large size of 70 µm are synthesized for high-performance DUV detection due to the large bandgap of 3.69 eV. Phototransistors based on the 2D ultrathin BiOBr nanoflakes deliver remarkable DUV detection performance including ultrahigh photoresponsivity (Rλ , 12739.13 A W-1 ), ultrahigh external quantum efficiency (EQE, 6.46 × 106 %), and excellent detectivity (D*, 8.37 × 1012 Jones) at 245 nm with a gate voltage (Vg ) of 35 V attributed to the photogating effects. The ultrafast response (τrise = 102 µs) can be achieved by utilizing photoconduction effects at Vg of -40 V. The combination of photocurrent generation mechanisms for BiOBr-based phototransistors controlled by Vg can pave a way for designing novel 2D optoelectronic materials to achieve optimal device performance.

Large-Scale Ultrathin 2D Wide-Bandgap BiOBr Nanoflakes for Gate-Controlled Deep-Ultraviolet Phototransistors

Highly efficient quantum-dot-sensitized solar cells with composite semiconductor of ZnO nanorod and oxide inverse opal in photoanode

A semiconductor oxide composite consisting of ZnO nanorods (NRs) and ZnO inverse opal (IO) was fabricated and used in the photoanode of quantum dot-sensitized solar cells (QDSSCs). Using polystyrene spheres 500, 800, 1000, and 1500 nm in diameter as the IO template, ZnO composites and corresponding QDSSCs with ZnO IOs of different pore sizes were fabricated. The oxide composite prepared with ZnO IOs of different pore sizes showed similar micro-morphologies; however, the photovoltaic performance of the QDSSCs based on these composites varied greatly. The QDSSCs based on the ZnO composite achieved high power conversion efficiencies (PCEs) of more than 6%, and the maximum PCE was 7.26% when the ZnO IO pore diameter in the composite was 800 nm. This resulted in very high PCE values for the QDSSCs using CdS/CdSe quantum dot sensitizers. With further interface modifications of NH4F and ZnS, the QDSSC achieved an even higher PCE value of 11.38%. Subsequently, the effects of ZnO IO pore size in the composite on QDSSC performance were investigated.

An investigation of the effects of ZnO inverse opal pore size in the composite of ZnO nanorods/ZnO inverse opal on the performance of quantum dot-sensitized solar cells.

Metal chalcogenides have been considered as one kind of the most promising anodes for lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs) due to their high capacities, thermal stabilities, and low price. However, the natural poor conductivity and large volume expansion of metal chalcogenides leading to a rapid capacity deterioration seriously makes them difficult for commercial applications. A 1D carbon-source nanostructure based on electrospinning can perfectly address the issues because of its cost-effectiveness, versatility, and controllability. Herein, we present a comprehensive review of the development of a metal chalcogenide nanomaterial by electrospinning for LIBs and SIBs. By subdividing various metal chalcogenide active materials, this Review focuses on the evolution in architectonics and the component of electrospun electrode materials. Particularly, the current progress of electrospun metal oxides, metal sulfides, and metal selenides materials of LIBs and SIBs has been appropriately discussed, respectively. Finally, the outlook of electrospun metal chalcogenide materials is also given. In the near future, the high-performance metal chalcogenide anodes via electrospinning will play an effective role in the promotion and application of LIBs and SIBs. Further, other advanced energy-storage devices can also draw on the experience from the design and fabrication of electrospun hierarchical materials. 

Recent Advances in Electrospun Metal Chalcogenide Anodes for Lithium-Ion and Sodium-Ion Batteries

MoOx/Au Schottky‐Gated Field‐Effect Transistors and Their Fast Inverters

In recent years, two-dimensional (2D) materials-based fundamental preparing process such as high-quality wafer-level single crystal thin film synthesis technology and high-performance electrode preparing technology has developed rapidly. In addition, the integrated application prospect of 2D materials has been preliminarily verified, owing to the flat and clean interface between 2D materials and substrates. From the perspective of electronics and optoelectronics based on 2D materials, this paper will summarize the recent studies of integrated circuit hardware, integrated optoelectronic hardware, and hetero-integrated hardware, showing their advantages and potential application. 

https://link.springer.com/content/pdf/10.1007/s11432-023-3744-2.pdf

Two-dimensional materials-based integrated hardware

Popular Tasks used by Researchers

How can I help with your research?

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

We encountered an error while loading the panel. Please try refreshing the page.

Something went wrong

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

Anyone with the link can view this chat. You can switch it back to private anytime.

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

Xiangxiang Yu

Author Tools

Chat about Author