Optical Properties and Light-Emission Device Applications of 2-D Layered Semiconductors

Recently two-dimensional layered semiconductors with promising electronic and optical properties have opened up a new way for applications in atomically thin electronics and optoelectronics.

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Fluorescent Nanotechnology: An Evolution in Optical Sensors

Current Analytical Chemistry ◽

10.2174/1573411017666201215121420 ◽

2020 ◽

Vol 17 ◽

Author(s):

Dilawar Hassan ◽

Hadi Bakhsh ◽

Asif M. Khurram ◽

Shakeel A. Bhutto ◽

Nida S. Jalbani ◽

...

Keyword(s):

Optical Properties ◽

Optical Sensors ◽

Light Emission ◽

Environmental Contaminants ◽

Fluorescent Nanoparticles ◽

Sensing Applications ◽

Properties Of Materials ◽

Optical Properties Of Materials ◽

Fluorescent Nanomaterials

Background: The optical properties of nanomaterials have evolved enormously with the introduction of nanotechnology. The property of materials to absorb and/or emit specific wavelength has turned them into one of the most favourite candidates to be effectively utilized in different sensing applications e.g organic light emission diodes (OLEDs) sensors, gas sensors, biosensors and fluorescent sensors. These materials have been reported as a sensor in the field of tissue and cell imaging, cancer detection and detection of environmental contaminants etc. Fluorescent nanomaterials are heling in rapid and timely detection of various contaminants that greatly impact the quality of life and food, that is exposed to these contaminants. Later, all the contaminants have been investigated to be most perilous entities that momentously affect the life span of the animals and humans who use those foods which have been contaminated. Objective: In this review, we will discuss about various methods and approaches to synthesize the fluorescent nanoparticles and quantum dots (QDs) and their applications in various fields. The application will include the detection of various environmental contaminants and bio-medical applications. We will discuss the possible mode of action of the nanoparticles when used as sensor for the environmental contaminants as well as the surface modification of some fluorescent nanomaterials with anti-body and enzyme for specific detection in animal kingdom. We will also describe some RAMAN based sensors as well as some optical sensing-based nanosensors. Conclusion: Nanotechnology has enabled to play with the size, shape and morphology of materials in the nanoscale. The physical, chemical and optical properties of materials change dramatically when they are reduced to nanoscale. The optical properties can become choosy in terms of emission or absorption of wavelength in the size range and can result in production of very sensitive optical sensor. The results show that the use of fluorescent nanomaterials for the sensing purposes are helping a great deal in the sensing field.

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Optical Properties of Zinc Sulphide Thin Films Coated with Aqueous Organic Dye Extract for Solar and Optoelectronic Device Applications

Journal of Electronic Materials ◽

10.1007/s11664-021-08792-0 ◽

2021 ◽

Vol 50 (5) ◽

pp. 2576-2583

Author(s):

Uche Paul Onochie ◽

Sunday Chukwuyem Ikpeseni ◽

Anthony Egwu Igweoko ◽

Hilary Ijeoma Owamah ◽

Chinecherem Collins Aluma ◽

...

Keyword(s):

Thin Films ◽

Optical Properties ◽

Optoelectronic Device ◽

Zinc Sulphide ◽

Organic Dye ◽

Device Applications

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Green Light Emission ofZnxCd1-xSeNanocrystals Synthesized by One-Pot Method

Journal of Nanomaterials ◽

10.1155/2013/526862 ◽

2013 ◽

Vol 2013 ◽

pp. 1-9 ◽

Cited By ~ 7

Author(s):

Shu-Ru Chung ◽

Kuan-Wen Wang ◽

Hong-Shuo Chen

Keyword(s):

Particle Size ◽

Optical Properties ◽

Light Emission ◽

Green Light ◽

Particle Size Effect ◽

Partial Replacement ◽

Face Centered Cubic ◽

One Pot ◽

Zn Content ◽

High Emission

We present a facile one-pot synthesis to prepare ternaryZnxCd1-xSe(x= 0.2, 0.5, 0.8, and 1) nanocrystals (NCs) with high emission quantum yield (QY, 45~89%). The effect of Zn content (x) ofZnxCd1-xSeNCs on their physical properties is investigated. The NCs have a particle size of 3.2 nm and face centered cubic structure. However, the actual compositions of the NCs are Zn0.03Cd0.97Se, Zn0.11Cd0.89Se, and Zn0.38Cd0.62Se when Zn content is 0.2, 0.5, and 0.8, respectively. In terms of the optical properties, the emission wavelength shifts from 512 to 545 nm with increasing Zn content from 0 to 0.8 while the QY changes from 89 to 45, respectively. Partial replacement of Cd by Zn is beneficial to improve the QY of Zn0.2and Zn0.5NCs. The optical properties of ternary NCs are affected by compositional effect rather than particle size effect.

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SiC Epitaxial Layers Grown by Sublimation Method and their Electrical Properties

Materials Science Forum ◽

10.4028/www.scientific.net/msf.556-557.153 ◽

2007 ◽

Vol 556-557 ◽

pp. 153-156

Author(s):

Chi Kwon Park ◽

Gi Sub Lee ◽

Ju Young Lee ◽

Myung Ok Kyun ◽

Won Jae Lee ◽

...

Keyword(s):

Electrical Properties ◽

Epitaxial Layer ◽

Light Emission ◽

Epitaxial Layers ◽

Current Voltage ◽

Space Technique ◽

Sublimation Method ◽

Device Applications ◽

P Type ◽

Surface Morphologies

A sublimation epitaxial method, referred to as the Closed Space Technique (CST) was adopted to produce thick SiC epitaxial layers for power device applications. In this study, we aimed to systematically investigate surface morphologies and electrical properties of SiC epitaxial layers grown with varying a SiC/Al ratio in a SiC source powder during the sublimation growth using the CST method. It was confirmed that the acceptor concentration of epitaxial layer was continuously decreased with increasing the SiC/Al ratio. The blue light emission was successfully observed on a PN diode structure fabricated with the p-type SiC epitaxial layer. Furthermore, 4H-SiC MESFETs having a micron-gate length were fabricated using a lithography process and their current-voltage performances were characterized.

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