scholarly journals Cascade surface modification of colloidal quantum dot inks enables efficient bulk homojunction photovoltaics

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Min-Jae Choi ◽  
F. Pelayo García de Arquer ◽  
Andrew H. Proppe ◽  
Ali Seifitokaldani ◽  
Jongmin Choi ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Surface Modification ◽  
Surface Chemistry ◽  
Surface Passivation ◽  
Diffusion Length ◽  
Power Conversion ◽  
Colloidal Quantum Dots ◽  
Semiconductor Materials ◽  
Colloidal Quantum Dot ◽  
Reduced Surface

AbstractControl over carrier type and doping levels in semiconductor materials is key for optoelectronic applications. In colloidal quantum dots (CQDs), these properties can be tuned by surface chemistry modification, but this has so far been accomplished at the expense of reduced surface passivation and compromised colloidal solubility; this has precluded the realization of advanced architectures such as CQD bulk homojunction solids. Here we introduce a cascade surface modification scheme that overcomes these limitations. This strategy provides control over doping and solubility and enables n-type and p-type CQD inks that are fully miscible in the same solvent with complete surface passivation. This enables the realization of homogeneous CQD bulk homojunction films that exhibit a 1.5 times increase in carrier diffusion length compared with the previous best CQD films. As a result, we demonstrate the highest power conversion efficiency (13.3%) reported among CQD solar cells.

Optical Characterization of CdSe Colloidal Quantum Dot/ MEH-PPV Polymer Nanocomposites Spin-cast on GaAs Substrates

2006 ◽  
Vol 939 ◽  
Author(s):  
Adrienne D. Stiff-Roberts ◽  
Abhishek Gupta ◽  
Zhiya Zhao
Keyword(s):  
Quantum Dots ◽  
Quantum Dot ◽  
Optoelectronic Devices ◽  
Photogenerated Electron ◽  
Polymer Nanocomposite ◽  
Colloidal Quantum Dots ◽  
Infrared Light ◽  
Gaas Substrates ◽  
Conducting Polymer Nanocomposite ◽  
Colloidal Quantum Dot

ABSTRACTThe motivation and distinct approach for this work is the use of intraband transitions within colloidal quantum dots for the detection of mid- (3-5 μm) and/or long-wave (8-14 μm) infrared light. The CdSe colloidal quantum dot/MEH-PPV conducting polymer nanocomposite material is well-suited for this application due to the ∼1.5 eV difference between the corresponding electron affinities. Therefore, CdSe colloidal quantum dots embedded in MEH-PPV should provide electron quantum confinement such that intraband transitions can occur in the conduction band. Further, it is desirable to deposit these nanocomposites on semiconductor substrates to enable charge transfer of photogenerated electron-hole pairs from the substrate to the nanocomposite. In this way, optoelectronic devices analogous to those achieved using Stranski-Krastanow quantum dots grown by epitaxy can be realized. To date, there have been relatively few investigations of colloidal quantum dot nanocomposites deposited on GaAs substrates. However, it is crucial to develop a better understanding of the optical properties of these hybrid material systems if such heterostructures are to be used for optoelectronic devices, such as infrared photodetectors. By depositing the nanocomposites on GaAs substrates featuring different doping characteristics and measuring the corresponding Fourier transform infrared absorbance, the feasibility of these intraband transitions is demonstrated at room temperature.

The effect of surface passivation on the structure of sulphur-rich PbS colloidal quantum dots for photovoltaic application

Nanoscale ◽  
2015 ◽  
Vol 7 (13) ◽  
pp. 5706-5711 ◽  
Author(s):  
Victor Malgras ◽  
Andrew Nattestad ◽  
Yusuke Yamauchi ◽  
Shi Xue Dou ◽  
Jung Ho Kim
Keyword(s):  
Quantum Dots ◽  
Structural Study ◽  
Surface Passivation ◽  
Colloidal Quantum Dots ◽  
Atmospheric Conditions ◽  
Photovoltaic Application ◽  
Pbs Quantum Dots ◽  
Effect Of Surface

In-depth structural study of methanol treated S-rich PbS quantum dots undergoing hydroxylation under atmospheric conditions.

Colloidal quantum dot ligand engineering for high performance solar cells

2016 ◽  
Vol 9 (4) ◽  
pp. 1130-1143 ◽  
Author(s):  
Ruili Wang ◽  
Yuequn Shang ◽  
Pongsakorn Kanjanaboos ◽  
Wenjia Zhou ◽  
Zhijun Ning ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Solar Cells ◽  
Quantum Dot ◽  
High Performance ◽  
Light Emitting Diodes ◽  
Optoelectronic Devices ◽  
Colloidal Quantum Dots ◽  
Solution Processed ◽  
Light Emitting ◽  
Colloidal Quantum Dot

Colloidal quantum dots (CQDs) are fast-improving materials for next-generation solution-processed optoelectronic devices such as solar cells, photocatalysis, light emitting diodes, and photodetectors.

scholarly journals Record Charge Carrier Diffusion Length in Colloidal Quantum Dot Solids via Mutual Dot-To-Dot Surface Passivation

2015 ◽  
Vol 27 (21) ◽  
pp. 3325-3330 ◽  
Author(s):  
Graham H. Carey ◽  
Larissa Levina ◽  
Riccardo Comin ◽  
Oleksandr Voznyy ◽  
Edward H. Sargent
Keyword(s):  
Quantum Dot ◽  
Charge Carrier ◽  
Surface Passivation ◽  
Diffusion Length ◽  
Carrier Diffusion ◽  
Colloidal Quantum Dot ◽  
Charge Carrier Diffusion

Surface Passivation of Luminescent Colloidal Quantum Dots with Poly(Dimethylaminoethyl methacrylate) through a Ligand Exchange Process

2004 ◽  
Vol 126 (25) ◽  
pp. 7784-7785 ◽  
Author(s):  
Xiao-Song Wang ◽  
Tieneke E. Dykstra ◽  
Mayrose R. Salvador ◽  
Ian Manners ◽  
Gregory D. Scholes ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Ligand Exchange ◽  
Surface Passivation ◽  
Exchange Process ◽  
Colloidal Quantum Dots ◽  
Dimethylaminoethyl Methacrylate

scholarly journals Phonon-assisted up-conversion photoluminescence of quantum dots

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Zikang Ye ◽  
Xing Lin ◽  
Na Wang ◽  
Jianhai Zhou ◽  
Meiyi Zhu ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Radiative Recombination ◽  
Power Conversion ◽  
Cost Effective ◽  
Colloidal Quantum Dots ◽  
Vibration Energy ◽  
Power Ratio ◽  
Radiative Recombination Rate ◽  
Temperature Dependent ◽  
Down Conversion

AbstractPhonon-assisted up-conversion photoluminescence can boost energy of an emission photon to be higher than that of the excitation photon by absorbing vibration energy (or phonons) of the emitter. Here, up-conversion photoluminescence power-conversion efficiency (power ratio between the emission and excitation photons) for CdSe/CdS core/shell quantum dots is observed to be beyond unity. Instead of commonly known defect-assisted up-conversion photoluminescence for colloidal quantum dots, temperature-dependent measurements and single-dot spectroscopy reveal the up-conversion photoluminescence and conventional down-conversion photoluminescence share the same electron-phonon coupled electronic states. Ultrafast spectroscopy results imply the thermalized excitons for up-conversion photoluminescence form within 200 fs, which is 100,000 times faster than the radiative recombination rate of the exciton. Results suggest that colloidal quantum dots can be exploited as efficient, stable, and cost-effective emitters for up-conversion photoluminescence in various applications.

scholarly journals Solution processed infrared- and thermo-photovoltaics based on 0.7 eV bandgap PbS colloidal quantum dots

Nanoscale ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 838-843 ◽  
Author(s):  
Yu Bi ◽  
Arnau Bertran ◽  
Shuchi Gupta ◽  
Iñigo Ramiro ◽  
Santanu Pradhan ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Quantum Dot ◽  
Heat Recovery ◽  
Waste Heat Recovery ◽  
Waste Heat ◽  
Solar Spectrum ◽  
Colloidal Quantum Dots ◽  
Solution Processed ◽  
Colloidal Quantum Dot

Colloidal quantum dot photovoltaics with a bandgap of 0.7 eV demonstrate potential to harness the infrared solar spectrum as well as in waste heat recovery.

scholarly journals Addition of Zn during the phosphine-based synthesis of indium phospide quantum dots: doping and surface passivation

2015 ◽  
Vol 6 ◽  
pp. 1237-1246 ◽  
Author(s):  
Natalia E Mordvinova ◽  
Alexander A Vinokurov ◽  
Oleg I Lebedev ◽  
Tatiana A Kuznetsova ◽  
Sergey G Dorofeev
Keyword(s):  
Quantum Dots ◽  
Surface Passivation ◽  
Particle Growth ◽  
Colloidal Quantum Dots ◽  
Synthetic Route ◽  
Zn Doping ◽  
Photochemical Etching ◽  
Wide Range ◽  
Dopant Atoms ◽  
First Time

Zinc-doped InP(Zn) colloidal quantum dots (QDs) with narrow size distribution and low defect concentration were grown for the first time via a novel phosphine synthetic route and over a wide range of Zn doping. We report the influence of Zn on the optical properties of the obtained quantum dots. We propose a mechanism for the introduction of Zn in the QDs and show that the incorporation of Zn atoms into the InP lattice leads to the formation of Zn acceptor levels and a luminescence tail in the red region of the spectra. Using photochemical etching with HF, we confirmed that the Zn dopant atoms are situated inside the InP nanoparticles. Moreover, doping with Zn is accompanied with the coverage of the QDs by a zinc shell. During the synthesis Zn myristate covers the QD nucleus and inhibits the particle growth. At the same time the zinc shell leads to an increase of the luminescence quantum yield through the reduction of phosphorous dangling bonds. A scenario for the growth of the colloidal InP(Zn) QDs was proposed and discussed.

Sign in / Sign up

Export Citation Format

Share Document