Article
Chemistry, Physical
Tom Galle, Daniel Spittel, Nelli Weiss, Volodymyr Shamraienko, Helena Decker, Maximilian Georgi, Rene Huebner, Nadia Metzkow, Christine Steinbach, Dana Schwarz, Vladimir Lesnyak, Alexander Eychmueller
Summary: The research transforms CdSe NPLs into PbSe NPLs suitable for optoelectronic applications through cation exchange, ligand exchange, and electronic coupling, successfully fabricating a photodetector with fast light response at low operational voltages on a commercial substrate.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Chemistry, Physical
Arun Ashokan, Paul Mulvaney
Summary: Solution-phase spectroelectrochemistry was used to study electron injection into colloidal CdSe quantum dots in THF. The results showed reversible optical changes on a time-scale of minutes, with the injection of electrons leading to quenching of photoluminescence. The number of electrons injected into the QDs depended on the electrode potential and QD size, with most injection occurring below the band edge.
CHEMISTRY OF MATERIALS
(2021)
Article
Chemistry, Physical
Jiakuan Zhang, Chuyue Li, Jiongzhao Li, Xiaogang Peng
Summary: Size- and shape-controlled CdSe/ZnSe core/shell and CdSe/ZnSe/ZnS core/shell/shell nanocrystals with zinc-blende structure are synthesized. The ligand strain between the inorganic crystal surface and organic ligands plays a key role in ZnSe epitaxy. The lattice strain between the CdSe and ZnSe affects the photoluminescence of CdSe/ZnSe/ZnS core/shell/shell QDs.
CHEMISTRY OF MATERIALS
(2023)
Article
Engineering, Electrical & Electronic
K. A. Rodriguez-Magdaleno, R. Perez-Alvarez, F. Ungan, J. C. Martinez-Orozco
Summary: In this work, we theoretically calculated the intraband absorption coefficient (IAC) between the 1s and 1p conduction band states for a spherical core/shell/shell quantum dot (CSS-QD). The effects of inner and outer shells' sizes and strain on the IAC were investigated. It was found that both strain and larger shell sizes resulted in a small redshift in the IAC. The findings highlight the importance of considering strain effects and the introduction of inner and outer shells in the design of nanostructures for controlling the IAC.
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
Jia Guo, Hualong Chen, Feng Zhang, Kaiyun Chen, S. Wageh, Ahmed A. Al-Ghamdi, Huanian Zhan, Wenlong He, Songrui Wei, Weichun Huang, Jun Liu, Han Zhang
Summary: This study successfully synthesized CdS@CdSe core-shell quantum dots and revealed their characteristics through femtosecond transient absorption studies and theoretical calculations, indicating their potential applications in optoelectronics and photovoltaics.
Article
Chemistry, Multidisciplinary
Grigor A. Mantashian, Paytsar A. Mantashyan, Hayk A. Sarkisyan, Eduard M. Kazaryan, Gabriel Bester, Sotirios Baskoutas, David B. Hayrapetyan
Summary: This study theoretically investigates exciton-related Raman scattering, interband absorption, and photoluminescence in colloidal CdSe/CdS core/shell quantum dots ensemble using numerical discretization method within the effective-mass approximation. The interband optical absorption and photoluminescence spectra for CdSe/CdS quantum dots are revealed, taking into account the size dispersion of the ensemble. Numerical calculation of the differential cross section for exciton-related Stokes-Raman scattering in CdSe/CdS quantum dots ensemble with different mean sizes is presented.
Article
Chemistry, Multidisciplinary
Rashid A. Ganeev, Andrey Zvyagin, Ivan A. Shuklov, Maksim G. Spirin, Oleg Ovchinnikov, Vladimir F. Razumov
Summary: InP@ZnS core-shell colloidal quantum dots were synthesized and characterized, with their nonlinear refraction and absorption coefficients determined using the z-scan technique. The study found saturable absorption and reverse saturable absorption phenomena in these CQDs, and demonstrated optical limiting effects within a certain intensity range. The research also discussed the thermal nature of negative nonlinear refraction in the studied species.
Article
Chemistry, Physical
Nina N. Kurus, Alexander G. Milekhin, Roman Sklyar, Bedil M. Saidzhonov, Roman B. Vasiliev, Sergei Adichtchev, Nikolai Surovtsev, Alexander Latyshev, Dietrich R. T. Zahn
Summary: The phonon spectra of core/shell CdSe/CdS nanoplatelets with different shell thicknesses were studied, revealing frequency shifts of optical modes as the shell thickness increases, which can be explained in terms of the stress state in the core and shell, as well as the influence of phonon confinement.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Multidisciplinary
Jacopo Pinna, Razieh Mehrabi Koushki, Dnyaneshwar S. Gavhane, Majid Ahmadi, Suhas Mutalik, Muhammad Zohaib, Loredana Protesescu, Bart J. Kooi, Giuseppe Portale, Maria Antonietta Loi
Summary: Nanoscale-level controlled ordering of colloidal quantum dots allows the achievement of outstanding transport properties, paving the way toward a new generation of optoelectronic devices.
ADVANCED MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Claudia Gollner, Rokas Jutas, Dominik Kreil, Dmitry N. Dirin, Simon C. Boehme, Andrius Baltuska, Maksym Kovalenko, Audrius Pugzlys
Summary: In this work, an all-optical femtosecond electro-absorption switch is presented, utilizing colloidal quantum dots, capable of high extinction contrast and transmission changes. The absence of physical artifacts allows for a simple numerical model to explain the electric field-induced electro-absorption response.
ADVANCED OPTICAL MATERIALS
(2022)
Article
Chemistry, Physical
Ja-Jung Koo, Kwang Hwan Jung, Kyungsu Park, Won Ja Min, Kyu-Sang Yu, Zee Hwan Kim, Jin-Kyu Lee
Summary: In this study, the interfacial structures of CdSe/ZnS QDs were investigated using TOF-MEIS. The results showed the existence of an alloyed layer at the interface between CdSe and ZnS in typical CdSe/ZnS QDs. The dissolution of CdSe seeds during the synthesis steps was identified as the cause of this interfacial alloying, and the ligand environment of the solvent was found to influence the shape of the interface.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Biochemical Research Methods
Olga A. Goryacheva, K. David Wegner, Aleksandr M. Sobolev, Ines Haeusler, Nikolai Gaponik, Irina Y. Goryacheva, Ute Resch-Genger
Summary: Light-emitting nanoparticles, known as quantum dots (QDs), have great potential for biosensing and bioimaging applications. However, their use in biological systems requires them to be water-dispersible without affecting their optical properties. In this study, researchers developed a new surface silanization method to preserve the optical properties of QDs and successfully prepared water-dispersible QDs.
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
(2022)
Review
Physics, Multidisciplinary
Um e Kalsoom, Rongxing Yi, Junle Qu, Liwei Liu
Summary: Recent research has shown that low-dimensional materials, such as quantum dots and core-shell quantum dots, exhibit strong nonlinear optical behavior and have potential applications in photo-electronics, photovoltaic nonlinear optics, light-emitting diode fabrication, and laser protections. Variations in core-shell shape and size, as well as the chemical composition of quantum dots, define their enhanced nonlinear optical properties. Specific nonlinear optical properties, such as nonlinear refraction, optical limiting, saturable absorption, and reverse saturable absorption of CdTe and CdSe quantum dots, along with core-shell quantum dots and their applications, were assessed in this study.
FRONTIERS IN PHYSICS
(2021)
Article
Chemistry, Physical
Bastiaan B. Salzmann, Jur de Wit, Chen Li, Daniel Arenas-Esteban, Sara Bals, Andries Meijerink, Daniel Vanmaekelbergh
Summary: This study prepared two-dimensional CdSe-PbSe heterostructures and PbSe NPLs through Pb2+-for-Cd2+ cation exchange and characterized the intermediary NCs with advanced microscopy and spectroscopy techniques. The growth of PbSe domains in CdSe NPLs occurs through the replacement of zinc blende CdSe lattice with rock salt PbSe phase while preserving the anion sublattice. Temperature-dependent emission measurements reveal size-dependent change of band gap energy and the influence of the anisotropic shape.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Optics
Yanqing Zhu, Cong Shen, Xueqing Xu, Jianhua Zou, Lei Wang, Xudong Cheng, Jingqiu Liang, Xiudi Xiao, Gang Xu
Summary: This study investigates the effect of halogen acid treatment on the luminescence properties of InP/GaP/ZnS quantum dots (QDs). It is found that hydrofluoric acid (HF) and hydrochloric acid (HCl) can improve the optical properties of QDs, while hydrobromic acid (HBr) and hydroiodic acid (HI) are not conductive to enhance the photoluminescence quantum yield (PL QY) of QDs. HF and HCl can effectively etch the oxidative layer and passivate the surface indium dangling bonds in the form of atomic ligands. The proposed charge carrier recombination model suggests that the significantly improved PL QY after acid treatment is attributed to the recombination of electron-hole pairs mainly from the conduction band and valence band. InP QDs treated with HF exhibit the best luminescence properties, with a high PL QY of 96%, offering great potential for advanced optoelectronic devices.
JOURNAL OF LUMINESCENCE
(2023)
