Solution Synthesis, Surface Passivation, Optical Properties, Biomedical Applications, and Cytotoxicity of Silicon and Germanium Nanocrystals

ChemPlusChem ◽  
2016 ◽  
Vol 82 (1) ◽  
pp. 60-73 ◽  
Author(s):  
Benjamin F. P. McVey ◽  
Sujay Prabakar ◽  
Justin J. Gooding ◽  
Richard D. Tilley
Keyword(s):  
Optical Properties ◽  
Biomedical Applications ◽  
Surface Passivation ◽  
Solution Synthesis ◽  
Germanium Nanocrystals ◽  
Silicon And Germanium

Investigation of the Surface Passivation Effect on the Optical Properties of CsPbBr3 Perovskite Quantum Dots

2021 ◽  
Vol 23 ◽  
pp. 100948
Author(s):  
Saif M.H. Qaid ◽  
Hamid M. Ghaithan ◽  
Bandar Ali Al-Asbahi ◽  
Abdullah S. Aldwayyan
Keyword(s):  
Quantum Dots ◽  
Optical Properties ◽  
Surface Passivation ◽  
Perovskite Quantum Dots

ZnO Nanoparticles, Nanorods, Hexagonal Plates and Nanosheets Produced by Polyol Route and the Effect of Surface Passivation by Acetate Molecules on Optical Properties

2019 ◽  
Vol 48 (10) ◽  
pp. 6437-6445
Author(s):  
Eduardo F. Barbosa ◽  
Jaqueline A. Coelho ◽  
Edna R. Spada ◽  
Daniel R. B. Amorim ◽  
Livia M. C. Souza ◽  
...  
Keyword(s):  
Optical Properties ◽  
Zno Nanoparticles ◽  
Surface Passivation ◽  
Effect Of Surface

Suppression of Halide Migration and Immobile Ionic Surface Passivation for Blue Perovskite Light-Emitting Diodes

2022 ◽  
Author(s):  
Chan Beom Park ◽  
Yun Seop Shin ◽  
Yung Jin Yoon ◽  
Hyungsu Jang ◽  
Jung Geon Son ◽  
...  
Keyword(s):  
Optical Properties ◽  
Light Emitting Diodes ◽  
Surface Passivation ◽  
Optoelectronic Properties ◽  
Light Emitting ◽  
Perovskite Nanocrystals

Cs-based perovskite nanocrystals (PeNCs) have been considered to be superb emitters for perovskite light-emitting diodes (PeLEDs) due to their remarkable optoelectronic properties. Still, poor optical properties are mainly attributed to...

scholarly journals Synthesis, Surface Modification and Purification of Silicon and Germanium Quantum Dots for Biological Applications

2021 ◽  
Author(s):  
◽  
Amane Shiohara
Keyword(s):  
Quantum Dots ◽  
Optical Properties ◽  
Silica Nanoparticles ◽  
Microemulsion System ◽  
Biological Applications ◽  
Silicon Quantum Dots ◽  
Surface Molecules ◽  
Silicon And Germanium ◽  
Germanium Quantum Dots ◽  
Oxygen Atoms

<p>Quantum dots have applications in biomedical fields such as bio-imaging and drug delivery systems. This thesis describes research on silicon and germanium nanoparticles (quantum dots) synthesis and surface modification for biological applications. Purification methods of these quantum dots were also explored. In chapter 6 the application of silica nanoparticles into dry eye diagnosis was studied. The purpose of this research is to contribute the application of nanotechnology into biological fields. The crystalinity of the quantum dots was characterised by Transmission Electron Microscopy (TEM) and Selected Area Electron Diffraction analysis (SAED). The molecules on the surface of the quantum dots were characterised by Fourier Transform Infrared spectroscopy (FTIR) and Nuclear Magnetic Resonance (NMR).  Silicon quantum dots were synthesised with a microemulsion system and various types of molecules were attached on the surface of the silicon quantum dots. However, some of the capping molecules which have oxygen atoms tend to form bonds between oxygen and silicon. Therefore, in the later chapter (chapter 4) various chemical reactions were conducted on the molecules attached to the silicon quantum dots. The silicon quantum dots were capped with diene molecules and one of the double bonds was left on the terminal end. The terminal end double bonds were converted to the functional groups which contain oxygen atoms to form peptide bonds. In this way it was confirmed that it can reduce the risk of oxygen atoms to be attached on the surface of the silicon quantum dots. The molecules on the surface of the silicon quantum dots were characterised mainly by FTIR and ¹H NMR. Optical properties and cyto-toxicity of these silicon quantum dots were also measured and analysed depending on the surface molecules.  Two synthetic approaches were taken to produce germanium quantum dots. The first approach was the microemulsion system at room temperature. Different combinations of the surfactant and capping molecules were tested. For the second approach, high temperature bench top system was applied. In this method the bio-friendly molecules which have high boiling points were chosen as capping agents. The surface molecules were characterised by FTIR spectroscopy.  In chapter 6 the synthesis of dye molecules conjugated silica nanoparticles was described. The purpose of this research is to produce biologically safe nanoparticles which can be applied in dry eye diagnosis. Three different dyes were used to conjugate with the silica nanoparticles. Only fluorescein isothiocyanate (FITC) succeeded in conjugating with the nanoparticles. Optical properties of this sample were measured and compared with the free dye molecule. Also the sample was applied in human eyes to analyse the tear film layer.  An overall conclusion and future plans for the research were given in the last chapter.In this chapter, ideas of overcoming the problems and improving the techniques conducted in the research were described.</p>

Optical Properties of Germanium Nanocrystals

1999 ◽  
Vol 175 (1) ◽  
pp. 23-31 ◽  
Author(s):  
M. Palummo ◽  
G. Onida ◽  
R. Del Sole
Keyword(s):  
Optical Properties ◽  
Germanium Nanocrystals

Upconversion lanthanide nanomaterials: basics introduction, synthesis approaches, mechanism and application in photodetector and photovoltaic devices

2021 ◽  
Author(s):  
Baharak Mehrdel ◽  
Ali Nikbakht ◽  
Azlan Abdul Aziz ◽  
Mahmood S. Jameel ◽  
Mohammed Ali Dheyab ◽  
...  
Keyword(s):  
Optical Properties ◽  
Near Infrared ◽  
Surface Passivation ◽  
Upconversion Emission ◽  
High Energy ◽  
Photovoltaic Devices ◽  
Plasmonic Enhancement ◽  
Host Matrix ◽  
Emission Enhancement ◽  
Improved Performance

Abstract Upconversion (UC) of lanthanide-doped nanostructure has the unique ability to convert low energy infrared (IR) light to high energy photons, which has significant potential for energy conversion applications. This review concisely discusses the basic concepts and fundamental theories of lanthanide nanostructures, synthesis techniques, and enhancement methods of upconversion for photovoltaic and for near-infrared (NIR) photodetector application. In addition, a few examples of lanthanide-doped nanostructures with improved performance were discussed, with particular emphasis on upconversion emission enhancement using coupling plasmon. The use of UC materials has been shown to significantly improve the NIR light-harvesting properties of photovoltaic devices and photocatalytic materials. However, the inefficiency of UC emission also prompted the need for additional modification of the optical properties of UC material. This improvement entailed the proper selection of the host matrix and optimization of the sensitizer and activator concentrations, followed by subjecting the UC material to surface-passivation, plasmonic enhancement, or doping. As expected, improving the optical properties of UC materials can lead to enhanced efficiency of photodetectors and photovoltaic devices.

Sign in / Sign up

Export Citation Format

Share Document