ORCID Profile
0000-0001-9053-5575
Current Organisations
International Iberian Nanotechnology Laboratory
,
Aaivalayam-DIRAC
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Publisher: Jenny Stanford Publishing
Date: 07-09-2017
Publisher: IOP Publishing
Date: 25-10-2016
DOI: 10.1088/0957-4484/27/46/462001
Abstract: Apart from conventional materials, the study of two-dimensional (2D) materials has emerged as a significant field of study for a variety of applications. Graphene-like 2D materials are important elements of potential optoelectronics applications due to their exceptional electronic and optical properties. The processing of these materials towards the realization of devices has been one of the main motivations for the recent development of photonics and optoelectronics. The recent progress in photonic devices based on graphene-like 2D materials, especially topological insulators (TIs) and transition metal dichalcogenides (TMDs) with the methodology level discussions from the viewpoint of state-of-the-art designs in device geometry and materials are detailed in this review. We have started the article with an overview of the electronic properties and continued by highlighting their linear and nonlinear optical properties. The production of TIs and TMDs by different methods is detailed. The following main applications focused towards device fabrication are elaborated: (1) photodetectors, (2) photovoltaic devices, (3) light-emitting devices, (4) flexible devices and (5) laser applications. The possibility of employing these 2D materials in different fields is also suggested based on their properties in the prospective part. This review will not only greatly complement the detailed knowledge of the device physics of these materials, but also provide contemporary perception for the researchers who wish to consider these materials for various applications by following the path of graphene.
Publisher: Royal Society of Chemistry (RSC)
Date: 2016
DOI: 10.1039/C5NR09111J
Abstract: Recent research on photodetectors has been mainly focused on nanostructured materials that form the building blocks of device fabrication. The selection of a suitable material with well-defined properties forms the key issue for the fabrication of photodetectors that cover different ranges of the electromagnetic spectrum. In this review, the latest progress in light detection using nanobelts, nanoribbons, nanosheets and the emerging two-dimensional (2D) materials is reviewed. Particular emphasis is placed on the detection of light by the hybrid structures of the mentioned nanostructured materials in order to enhance the efficiency of the light-matter interaction. The booming research area of black phosphorus based photo-detection is also reviewed. This review provides an overview of basic concepts and new directions towards photodetectors, and highlights potential for the future development of high performance broadband photodetectors.
Publisher: Wiley
Date: 07-08-2017
Publisher: Wiley
Date: 07-02-2017
Publisher: American Chemical Society (ACS)
Date: 14-12-2016
Abstract: Vertical heterojunctions of two two-dimensional (2D) transition metal dichalcogenides (TMDs) have attracted considerable attention recently. A variety of heterojunctions can be constructed by stacking different TMDs to form fundamental building blocks in different optoelectronic devices such as photodetectors, solar cells, and light-emitting diodes. However, these applications are significantly h ered by the challenges of large-scale production of van der Waals stacks of atomically thin materials. Here, we demonstrate scalable production of periodic patterns of few-layer WS2, MoS2, and their vertical heterojunction arrays by a thermal reduction sulfurization process. In this method, a two-step chemical vapor deposition approach was developed to effectively prevent the phase mixing of TMDs in an unpredicted manner, thus affording a well-defined interface between WS2 and MoS2 in the vertical dimension. As a result, large-scale, periodic arrays of few-layer WS2, MoS2, and their vertical heterojunctions can be produced with desired size and density. Photodetectors based on the as-produced MoS2/WS2 vertical heterojunction arrays were fabricated, and a high photoresponsivity of 2.3 A·W(-1) at an excitation wavelength of 450 nm was demonstrated. Flexible photodetector devices using MoS2/WS2 heterojunction arrays were also demonstrated with reasonable signal/noise ratio. The approach in this work is also applicable to other TMD materials and can open up the possibilities of producing a variety of vertical van der Waals heterojunctions in a large scale toward optoelectronic applications.
Publisher: American Chemical Society (ACS)
Date: 15-05-2015
Abstract: Two-dimensional layered transition metal dichalcogenides (TMDs) show intriguing potential for optoelectronic devices due to their exotic electronic and optical properties. Only a few efforts have been dedicated to large-area growth of TMDs. Practical applications will require improving the efficiency and reducing the cost of production, through (1) new growth methods to produce large size TMD monolayer with less-stringent conditions, and (2) nondestructive transfer techniques that enable multiple reuse of growth substrate. In this work, we report to employ atmospheric pressure chemical vapor deposition (APCVD) for the synthesis of large size (>100 μm) single crystals of atomically thin tungsten disulfide (WS2), a member of TMD family, on sapphire substrate. More importantly, we demonstrate a polystyrene (PS) mediated delamination process via capillary force in water which reduces the etching time in base solution and imposes only minor damage to the sapphire substrate. The transferred WS2 flakes are of excellent continuity and exhibit comparable electron mobility after several growth cycles on the reused sapphire substrate. Interestingly, the photoluminescence emission from WS2 grown on the recycled sapphire is much higher than that on fresh sapphire, possibly due to p-type doping of monolayer WS2 flakes by a thin layer of water intercalated at the atomic steps of the recycled sapphire substrate. The growth and transfer techniques described here are expected to be applicable to other atomically thin TMD materials.
Location: North Macedonia
Location: Italy
Location: Italy
No related grants have been discovered for Joice Sophia Ponraj.