A5090956533- Quantum Dots Synthesis And Properties
- Chalcogenide Semiconductor Thin Films
- Perovskite Materials and Applications
- Gold and Silver Nanoparticles Synthesis and Applications
- Nanocluster Synthesis and Applications
- Photonic Crystals and Applications
- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Photonic and Optical Devices
- Nonlinear Optical Materials Studies
- Nanoplatforms for cancer theranostics
- Nanoparticle-Based Drug Delivery
- Luminescence Properties of Advanced Materials
- Semiconductor Lasers and Optical Devices
- Essential Oils and Antimicrobial Activity
- Laser-Ablation Synthesis of Nanoparticles
- Pickering emulsions and particle stabilization
- Iron oxide chemistry and applications
- Electrowetting and Microfluidic Technologies
- Medicinal Plant Research
- Solid-state spectroscopy and crystallography
- Molecular Junctions and Nanostructures
- Photochemistry and Electron Transfer Studies
- Ocular and Laser Science Research
- Nuclear and radioactivity studies
Physikalisch-Technische Bundesanstalt
2025
Bilkent University
2015-2024
Sağlık Bilimleri Üniversitesi
2021-2024
Ghent University
2021-2024
Ministry of Health
2024
National Nanotechnology Research Center
2024
Ankara Sosyal Bilimler Üniversitesi
2021
Ankara University
2019
Nanyang Technological University
2017
Turkish Armed Forces
2016
Colloidal semiconductor quantum wells, also commonly known as nanoplatelets (NPLs), have arisen among the most promising materials for light generation and harvesting applications. Recently, NPLs been found to assemble in stacks. However, their emerging characteristics essential these applications not previously controlled or understood. In this report, we systematically investigate present excitonic properties of column-like NPL assemblies. Here, by a gradual process, show that stacking...
Here, the CdSe/CdS@CdS core/crown@shell heterostructured nanoplatelets (NPLs) resembling a platelet‐in‐box structure are developed and successfully synthesized. It is found that NPLs exhibit consistently substantially improved photoluminescence quantum yield compared to core@shell regardless of their CdSe‐core size, CdS‐crown CdS‐shell thickness. This enhancement in attributed passivation trap sites resulting from critical peripheral growth with laterally extending layer before vertical...
Colloidal semiconductor nanoplatelets (NPLs) offer important benefits in nanocrystal optoelectronics with their unique excitonic properties. For NPLs, colloidal atomic layer deposition (c-ALD) provides the ability to produce core/shell heterostructures. However, as c-ALD takes place at room temperature, this technique allows for only limited stability and low quantum yield. Here, highly stable, near-unity efficiency CdSe/ZnS NPLs are shown using hot-injection (HI) shell growth performed 573...
Abstract Surface effects in atomically flat colloidal CdSe nanoplatelets (NLPs) are significantly and increasingly important with their thickness being reduced to subnanometer level, generating strong surface related deep trap photoluminescence emission alongside the bandedge emission. Herein, synthesis of highly luminescent two‐monolayer (2ML) NPLs a systematic investigation carrier dynamics these exhibiting broad covering visible region quantum yields reaching 90% solution 85% polymer...
We proposed and showed strongly orientation-controlled Förster resonance energy transfer (FRET) to highly anisotropic CdSe nanoplatelets (NPLs). For this purpose, we developed a liquid–air interface self-assembly technique specific depositing complete monolayer of NPLs only in single desired orientation, either fully stacked (edge-up) or nonstacked (face-down), with near-unity surface coverage across large areas over 20 cm2. These NPL monolayers were employed as acceptors an working model...
We propose and demonstrate construction of highly uniform, multilayered superstructures CdSe/CdZnS core/shell colloidal nanoplatelets (NPLs) using liquid interface self-assembly. These NPLs are sequentially deposited onto a solid substrate into slabs having monolayer-precise thickness across tens cm2 areas. Because near-unity surface coverage excellent uniformity, amplified spontaneous emission (ASE) is observed from an uncharacteristically thin film 6 NPL layers, corresponding to mere 42 nm...
Metal halide perovskites are one of the most investigated materials in optoelectronics, with their lead-based counterparts being renowned for enhanced optoelectronic performance. The 3D CsPbX3 structure has set standard many studies currently attempting to substitute lead other metals while retaining properties this material. This effort led fabrication metal halides lower dimensionality, wherein particular 2D layered perovskite structures have captured attention as inspiration next...
In this study, nonradiative energy transfer was investigated in solid thin films of colloidal nanoplatelets incorporating two different vertical thicknesses.
Here, we designed and synthesized alloyed heterostructures of CdSexS1–x nanoplatelets (NPLs) using CdS coating in the lateral vertical directions for achievement highly tunable optical gain performance. By homogeneously core NPLs as a seed, prepared CdSexS1–x/CdS core/crown NPLs, where crown region is extended only direction. With sidewall passivation around inner cores, achieved enhanced photoluminescence quantum yield (PL-QY) (reaching 60%), together with increased absorption cross-section...
Here we designed and synthesized CdSe/CdSe1–xTex core/crown nanoplatelets (NPLs) with controlled crown compositions by using the core-seeded-growth approach. We confirmed uniform growth of regions well-defined shape employing transmission electron microscopy, X-ray photoelectron spectroscopy, diffraction. By precisely tuning composition CdSe1–xTex region from pure CdTe (x = 1.00) to almost CdSe doped several Te atoms 0.02), achieved tunable excitonic properties without changing thickness...
Highly efficient aqueous quantum wells are obtained from composition-tuned gradient shells with monolayer precision.
Semiconductor colloidal quantum wells (CQWs) provide anisotropic emission behavior originating from their optical transition dipole moments (TDMs). Here, solution-processed well light-emitting diodes (CQW-LEDs) of a single all-face-down oriented self-assembled monolayer (SAM) film CQWs that collectively enable supreme level IP TDMs at 92% in the ensemble are shown. This significantly enhances outcoupling efficiency 22% (of standard randomly-oriented emitters) to 34% face-down LED. As result,...
A hybrid structure of the quasi-2D colloidal semiconductor quantum wells assembled with a single layer 2D transition metal dichalcogenides offers possibility highly strong dipole-to-dipole coupling, which may enable extraordinary levels efficiency in Förster resonance energy transfer (FRET). Here, we show ultrahigh-efficiency FRET from ensemble thin films CdSe/CdS nanoplatelets (NPLs) to MoS2 monolayer. From time-resolved fluorescence spectroscopy, observed suppression photoluminescence NPLs...
We systematically studied temperature-dependent emission kinetics in solid films of solution-processed CdSe nanoplatelets (NPLs) that are either intentionally stacked or nonstacked. observed the steady-state photoluminescence (PL) intensity nonstacked NPLs considerably increases with decreasing temperature, whereas there is only a slight increase NPLs. Furthermore, PL decay time NPL ensemble comparatively much shorter than NPLs, and this result consistent at all temperatures. To account for...
We describe a study of the magneto-optical properties Ag+-doped CdSe colloidal nanoplatelets (NPLs) that were grown using novel doping technique. In this work, we used magnetic circularly polarized luminescence and circular dichroism spectroscopy to light-induced magnetism for first time in 2D solution-processed structures doped with nominally nonmagnetic Ag+ impurities. The excitonic polarization (PX) exciton Zeeman splitting (ΔEZ) recorded as function field (B) temperature (T). Both ΔEZ PX...
Abstract The realization of high‐quality lasers in microfluidic devices is crucial for numerous applications, including biological and chemical sensors flow cytometry, the development advanced lab‐on‐chip (LOC) devices. Herein, an ultralow‐threshold single‐mode laser proposed demonstrated using on‐chip cavity. CdSe/CdS@Cd x Zn 1− S core/crown@gradient‐alloyed shell colloidal semiconductor quantum wells (CQWs) dispersed toluene are employed cavity created inside a poly(dimethylsiloxane)...
We demonstrate amplified spontaneous emission (ASE) in solution with ultralow thresholds of 30 μJ/cm2 red and 44 green from engineered colloidal quantum well (CQW) heterostructures. For this purpose, CdSe/CdS core/crown CQWs, designed to hit the region, CdSe/CdS@CdxZn1–xS core/crown@gradient-alloyed shell further tuned reach region by alloying, were employed achieve high-performance ASE visible range. The net modal gain these CQWs reaches 530 cm–1 for 201 red, 2–3 orders magnitude larger...
Here, the first account of self-resonant fully-colloidal u-lasers made from colloidal quantum well (CQW) solution is reported. A deep patterning technique developed to fabricate well-defined high aspect-ratio on-chip CQW resonators grating waveguides and in-plane reflectors. CQWs patterned layers are closed-packed with sharp edges residual-free lifted-off surfaces. Additionally, method successfully applied various nanoparticles including dots metal nanoparticles. It observed that process...
For their unique optical properties, quantum dots (QDs) have been extensively used as light emitters in a number of photonic and optoelectronic applications. They even met commercialization success through implementation high-end displays with unmatched brightness color rendering. such applications, however, QDs must be shielded from oxygen water vapor, which are known to degrade properties over time. Even highly qualitative QDs, this can only achieved encapsulation between barrier layers....
Semiconductor lead halide perovskites are excellent candidates for realizing low threshold light amplification due to their tunable and highly efficient luminescence, ease of processing, strong light–matter interactions. However, most studies on optical gain have addressed bulk films, nanowires, or nanocrystals that exhibit little no size quantization. Here, we show by means a multitude spectroscopy methods small CsPbBr3 (NCs) progressive red shift the band-edge transition upon addition...
With the International Commission on Radiological Protection (ICRP) lowering annual dose limit for eye lens to 20 mSv, precise monitoring of exposure has become essential. The personal equivalent at a depth 3 mm, Hp(3), is measurement method eye. Traditional dosimetry methods primarily address lateral radiation scenarios, where approaches from left or right, necessitating rotation phantom during type testing around vertical axis. However, these do not adequately account bottom-to-top...
The outstanding opto-electronic properties of lead halide perovskites have been related to the formation polarons. Nevertheless, observation atomistic deformation brought about by one electron-hole pair in these materials has remained elusive. Here, we measure diffraction patterns single CsPbBr$_3$ quantum dots (QDs) with and without resonant excitation exciton limit using serial femtosecond crystallography (SFX). By reconstructing 3D differential pattern, observe small shifts Bragg peaks...