scholarly journals Timing matters: the underappreciated role of temperature ramp rate for shape control and reproducibility of quantum dot synthesis

Nanoscale ◽  
2012 ◽  
Vol 4 (12) ◽  
pp. 3625 ◽  
Author(s):  
William J. Baumgardner ◽  
Zewei Quan ◽  
Jiye Fang ◽  
Tobias Hanrath
Keyword(s):  
Quantum Dot ◽  
Shape Control ◽  
Ramp Rate ◽  
Temperature Ramp

Co-Implantation and the Role of Implant Damage in the Thermal Stability of Implanted Helium in Indium Phosphide

2000 ◽  
Vol 647 ◽  
Author(s):  
Todd W. Simpson ◽  
Ian V. Mitchell
Keyword(s):  
Thermal Stability ◽  
Elevated Temperature ◽  
Indium Phosphide ◽  
Bubble Formation ◽  
Ramp Rate ◽  
Temperature Range ◽  
Temperature Ramp ◽  
Ion Species ◽  
Thermal Stability Of

AbstractThe thermal stability of 3He implanted into single crystal indium phosphide has been studied. Helium diffuses in the 200°C-300°C temperature range unless stabilized by bubbles which trap helium up to the 400°C-500°C temperature range. The efficiency of bubble formation, as measured by the fraction of implanted helium retained to 400°C is increased by: 1) increasing the helium fluence, 2) increasing the temperature ramp rate, 3) co-implantation with a second ion species, or 4) implanting at elevated temperature. The mechanism by which these processes enhance bubble formation can be understood in terms of a model where the nucleation of bubbles occurs at elevated temperature in the presence of both lattice defects and helium atoms.

scholarly journals Deciphering the role of quantum dot size in the ultrafast charge carrier dynamics at the perovskite–quantum dot interface

2020 ◽  
Vol 8 (42) ◽  
pp. 14834-14844
Author(s):  
Piotr Piatkowski ◽  
Sofia Masi ◽  
Pavel Galar ◽  
Mario Gutiérrez ◽  
Thi Tuyen Ngo ◽  
...  
Keyword(s):  
Quantum Dot ◽  
Charge Carrier ◽  
Rate Constants ◽  
Transient Absorption ◽  
Carrier Dynamics ◽  
Carrier Transfer ◽  
Charge Carrier Dynamics ◽  
Conduction Bands

Charge-carrier transfer (CT) from the perovskite host to PbS QDs were studied using fs-transient absorption and THz techniques. The CT rate constants increase with the size of QDs due to a change in the position of valence and conduction bands in PbS QDs.

Evolutionary Shape Control During Colloidal Quantum-Dot Growth

Small ◽  
2007 ◽  
Vol 3 (3) ◽  
pp. 481-487 ◽  
Author(s):  
P. Sreekumari Nair ◽  
Karolina P. Fritz ◽  
Gregory D. Scholes
Keyword(s):  
Quantum Dot ◽  
Shape Control ◽  
Colloidal Quantum Dot

Variable Ramp Rate Breakdown Experiments and the Role of Metal Injection in Low- $k$ Dielectrics

2011 ◽  
Vol 58 (12) ◽  
pp. 4354-4360 ◽  
Author(s):  
Joel L. Plawsky ◽  
Juan Borja ◽  
Brian Williams ◽  
Michael J. Riley ◽  
William N. Gill
Keyword(s):  
Ramp Rate ◽  
Low K

Quantum Dot Solar Cells. Tuning Photoresponse through Size and Shape Control of CdSe−TiO2Architecture

2008 ◽  
Vol 130 (12) ◽  
pp. 4007-4015 ◽  
Author(s):  
Anusorn Kongkanand ◽  
Kevin Tvrdy ◽  
Kensuke Takechi ◽  
Masaru Kuno ◽  
Prashant V. Kamat
Keyword(s):  
Solar Cells ◽  
Quantum Dot ◽  
Shape Control ◽  
Size And Shape ◽  
Quantum Dot Solar Cells

scholarly journals Synthesis of Platinum Nanocrystals within Iodine Ions Mediated

2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Jiamao Li ◽  
Jingwei Hou ◽  
Yu Gong ◽  
Chengjian Xiao ◽  
Lei Yue ◽  
...  
Keyword(s):  
Shape Control ◽  
Growth Process ◽  
Growth Stage ◽  
Nucleation Stage ◽  
Platinum Nanocrystals ◽  
High Resolution Tem ◽  
Pt Nanocrystals ◽  
High Concentrations ◽  
Insight Into

A liquid-phase reducing method of synthesizing Pt nanocrystals was demonstrated, and dendrite-, cube-, and cuboctahedron-shaped Pt nanocrystals (NCs) with well-defined monomorphic were successfully synthesized through iodine ions mediated with the CTAB agent. When the KI concentration was increased to thirty times of K2PtCl4 at the nucleation stage, the high-quality Pt nanodendrites could be obtained. However, no matter how many KI were added at the growth age, only cube- and cuboctahedron-shaped Pt nanocrystals formed. The results of high-resolution TEM, EDX, and XRD indicated that the size and shape of Pt NCs could be turned by changing the concentration and time of KI. In the nucleation stage, it might be due to that some iodine ions adsorb on the surfaces of Pt NCs, which probably cause the rapid growth process resulting in the formation of Pt nanodendrites. In the growth stage, although high concentrations of I− ions could contribute to the shape control and generate bigger particles of Pt NCs, small Pt particles do not grow into dendrites. The insight into the role of I− ions in synthesis of Pt NCs reported here provided a viewpoint for clearly understanding the formation mechanism of anisotropic platinum nanostructures.

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