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
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
Crystallography
Quinton Rice, Sangram Raut, Kyle Burney, Zygmunt Gryczynski, Ignacy Gryczynski, William W. Yu, Bagher Tabibi, Jaetae Seo
Summary: The broadband spontaneous emission of excitons in CdSe quantum dots is of great interest for spectral imaging in living organisms or in the near infrared spectral region. As the dot size decreases, the role of surface-trapped states increases, introducing new electronic transitions.
Article
Chemistry, Multidisciplinary
Katherine E. Shulenberger, Sophie C. Coppieters 't Wallant, Megan D. Klein, Alexandra R. McIsaac, Tamar Goldzak, David B. Berkinsky, Hendrik Utzat, Ulugbek Barotov, Troy Van Voorhis, Moungi G. Bawendi
Summary: A spectrally resolved correlation method was developed to study the triply excited state, enabling direct measurements of the recombination pathway for the triexciton. It was found that for core-shell CdSe-CdS nanocrystals, triexciton emission arises exclusively from the band-edge S-like state. Time-dependent density functional theory and extended particle-in-a-sphere calculations show that reduced carrier overlap induced by the core-shell heterostructure can account for the lack of emission observed from the P-like state. These results provide insights for potential control of nanocrystal luminescence using core-shell heterostructures.
Article
Chemistry, Analytical
Dongquan Leng, Jihao Zhao, Xiang Ren, Rui Xu, Lei Liu, Xuejing Liu, Yuyang Li, Qin Wei
Summary: In this study, a split-type immunoassay strategy initiated by cation exchange and altering the capacity of an electron donor was optimized, using MoSe2/CdSe as a photoelectrode substrate and silver ions as the initiator of CE. The combination of ascorbate oxidase with MSNs improved the sensor's sensitivity and reliability, resulting in a broad linear range and low detection limit when applied to neuron-specific enolase.
ANALYTICAL CHEMISTRY
(2021)
Article
Chemistry, Physical
Zefan Zhang, Christian Hilty
Summary: The reversible adsorption of CO2-derived species to graphene quantum dots in CO2 electroreduction reaction was characterized using nuclear spin hyperpolarized NMR. The study found a significant difference in the relaxation rates of bound and free species, indicating reversible binding. pH-dependent adsorption and desorption rate constants were measured, along with the average binding distance.
Article
Nanoscience & Nanotechnology
Christoph P. Theurer, Antonia Weber, Martin Richter, Markus Bender, Patrick Michel, Debkumar Rana, Krishan Kumar, Uwe Bunz, Marcus Scheele, Petra Tegeder, Frank Schreiber, Katharina Broch
Summary: Hybrid organic-inorganic nanomaterials, which combine organic semiconductors and inorganic quantum dots, show promise for opto-electronic devices in a sustainable internet of things. However, the lack of understanding of the organic-inorganic interface has been a major challenge in widespread device applications. By studying a specific system, the short-range organization and binding motif of aryleneethynylenes coupled to CdSe QDs, we have made advancements in understanding this interface and identified the incorporation of the organic ligands in between the inorganic QDs.
Article
Chemistry, Physical
A. D. Kurilov, D. N. Chausov, V. V. Osipova, R. N. Kucherov, V. V. Belyaev, Y. G. Galyametdinov
Summary: This work focuses on synthesizing highly luminescent hybrid CdSe/CdS core/shell quantum dots and doping them into a nematic liquid crystal to obtain new composites. The sizes of the quantum dot cores and additional ZnS shells are correlated with the luminescence and dielectric characteristics of the composites.
JOURNAL OF MOLECULAR LIQUIDS
(2021)
Article
Nanoscience & Nanotechnology
Matteo Barelli, Cynthia Vidal, Sergio Fiorito, Alina Myslovska, Dimitrie Cielecki, Vincenzo Aglieri, Iwan Moreels, Riccardo Sapienza, Francesco Di Stasio
Summary: This study demonstrates the controlled placement of colloidal semiconductor nanocrystals onto planar surfaces by patterning nanohole arrays in a PMMA thin film and trapping the nanocrystals into the holes. The resulting arrays contain hundreds of single-photon emitters, providing a feasible, fast, and practical method for the fabrication of nanodevices based on colloidal semiconductor nanocrystals, such as single-photon-emitting LEDs.
Article
Physics, Applied
Xi-Kai Yang, Jia-Wei Qiao, Zhi-Hao Chen, Zhen-Chuan Wen, Hang Yin, Xiao-Tao Hao
Summary: By incorporating CdSe quantum dots as a third component, this study has successfully enhanced the current density and power conversion efficiency of organic solar cells. CdSe QDs modulate charge dynamics, increase fluorescence external quantum efficiency, and enable Forster resonance energy transfer and fast charge transfer in BHJ films, resulting in improved overall device performance.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2021)
Article
Chemistry, Multidisciplinary
Hui Zhang, Xiaohu Mi, Bowen Kang, Yunkai Wu, Tingting Zhang, Pai Liu, Xiaowei Sun, Zhenglong Zhang, Ning Liu, Hongxing Xu
Summary: Colloidal nanocrystals play a significant role in optoelectronic devices and their properties can be improved through ligand modification, which can enhance charge transport and emission characteristics in LEDs.
Article
Multidisciplinary Sciences
E. D. Herbschleb, H. Kato, T. Makino, S. Yamasaki, N. Mizuochi
Summary: The authors demonstrate a non-adaptive algorithm to increase the sensing range while approaching the best sensitivity, outperforming the standard measurement concept in both sensitivity and range. They thoroughly explore this algorithm by simulation and discuss the T-2 scaling in the coherent regime, contrasting it with the T-1/2 of the standard measurement. This algorithm can be applied to any modulo-limited sensor.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Physical
Prachi Rastogi, Eva Izquierdo, Charlie Greboval, Mariarosa Cavallo, Audrey Chu, Tung Huu Dang, Adrien Khalili, Claire Abadie, Rodolphe Alchaar, Stefano Pierini, Herve Cruguel, Nadine Witkowski, James K. Utterback, Thibault Brule, Xiang Zhen Xu, Philippe Hollander, Abdelkarim Ouerghi, Bruno Gallas, Mathieu G. Silly, Emmanuel Lhuillier
Summary: Researchers have developed a new photodiode design that integrates nanocrystals into focal plane arrays, achieving efficient charge dissociation and low dark current. By introducing a thin and strongly coupled CdSe layer, the electrical performance of the diode is significantly improved.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Multidisciplinary
Gang Qiang, Aleksandr A. Golovatenko, Elena V. Shornikova, Dmitri R. Yakovlev, Anna V. Rodina, Evgeny A. Zhukov, Ina V. Kalitukha, Victor F. Sapega, Vadim Kh. Kaibyshev, Mikhail A. Prosnikov, Peter C. M. Christianen, Aleksei A. Onushchenko, Manfred Bayer
Summary: Exciton recombination dynamics and spin polarization in CdSe nanocrystals synthesized in a glass matrix were investigated using polarized photoluminescence in high magnetic fields up to 30 Tesla. The study revealed that the dynamics are accelerated by increasing temperature and magnetic field, and circularly polarized photoluminescence in magnetic fields showed several unusual appearances. The observed features were explained by a theoretical model, highlighting the competition between different recombination channels and the inhomogeneous broadening of the photoluminescence spectrum from the ensemble of nanocrystals.
Article
Chemistry, Physical
Prachi Rastogi, Eva Izquierdo, Charlie Greboval, Mariarosa Cavallo, Audrey Chu, Tung Huu Dang, Adrien Khalili, Claire Abadie, Rodolphe Alchaar, Stefano Pierini, Herve Cruguel, Nadine Witkowski, James K. Utterback, Thibault Brule, Xiang Zhen Xu, Philippe Hollander, Abdelkarim Ouerghi, Bruno Gallas, Mathieu G. Silly, Emmanuel Lhuillier
Summary: This study improved the design of nanocrystal integration into focal plane arrays by introducing a CdSe layer, significantly enhancing the electrical performance and achieving high responsivity and specific detectivity.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Multidisciplinary
Johanna C. van der Bok, P. Tim Prins, Federico Montanarella, D. Nicolette Maaskant, Floor A. Brzesowsky, Maaike M. van der Sluijs, Bastiaan B. Salzmann, Freddy T. Rabouw, Andrei Petukhov, Celso De Mello Donega, Daniel Vanmaekelbergh, Andries Meijerink
Summary: Researchers found through in situ studies that in the early stage of the CdSe nanoplatelet reaction, both isotropic nanocrystals and mini-nanoplatelets form in the absence of short-chain ligands, but most precursors are consumed in isotropic growth. The addition of acetate induces a dramatic shift towards nearly exclusive 2D growth of already existing mini-nanoplatelets. Therefore, mature nanoplatelets only grow through a subtle interplay between myristate and acetate, with the latter catalyzing fast lateral growth of the side facets of the mini-nanoplatelets.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Multidisciplinary
Adi Harchol, Yahel Barak, Kira E. Hughes, Kimberly H. Hartstein, Huygen J. Jobsis, P. Tim Prins, Celso de Mello Donega, Daniel R. Gamelin, Efrat Lifshitz
Summary: This study elucidates the recombination processes and spin properties of copper-doped CdSe/CdS and CuInS2 colloidal quantum dots (CQDs) using optically detected magnetic resonance spectroscopy. The findings support different models for the magneto-optical properties of these important materials.
Article
Chemistry, Physical
Serena Busatto, Claudia Spallacci, Johannes D. Meeldijk, Stuart Howes, Celso de Mello Donega
Summary: This study reported the room temperature synthesis of ultrathin CdTe magic-size nanowires, revealing their growth mechanism and the crucial role of primary alkylamines in the growth process.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Physical
P. Tim Prins, Dirk A. W. Spruijt, Mark J. J. Mangnus, Freddy T. Rabouw, Daniel Vanmaekelbergh, Celso de Mello Donega, Pieter Geiregat
Summary: Impurity doping of III-V colloidal quantum dots remains underexplored. This study shows that electron cooling is fast in copper-doped InP quantum dots, while hole localization is slow but still leads to efficient luminescence.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Chemistry, Multidisciplinary
Sergii Morozov, Stefano Vezzoli, Alina Myslovska, Alessio Di Giacomo, N. Asger Mortensen, Iwan Moreels, Riccardo Sapienza
Summary: Giant shell CdSe/CdS quantum dots exhibit high brightness and flexibility, with near-unity quantum yield and suppressed blinking. However, their single photon purity is reduced due to efficient multiexcitonic emission. In this study, we observed a significant blueshift in the photoluminescence biexciton spectrum of pure-phase wurtzite quantum dots. By using spectral filtering, we achieved a 2.3 times reduction in biexciton quantum yield while preserving 60% of the exciton single photon emission, leading to an improvement in purity from g2(0)=0.07±0.01 to g2(0)=0.03±0.01. Furthermore, at higher pump fluence, the spectral purification was even more effective, resulting in up to a 6.6 times reduction in g2(0) by suppressing higher order excitons and shell states with larger blueshifts.
Article
Microbiology
Catherine Cesa-Luna, Niels Geudens, Lea Girard, Vic De Roo, Hassan R. Maklad, Jose C. Martins, Monica Hofte, Rene De Mot
Summary: By mining the genomes of Pseudomonas species, we have mapped the global Pseudomonas lipopeptidome and found its impressive diversity to be linked to taxonomy of the producers. The synthesis of lipopeptides is facilitated by nonribosomal peptide synthetases (NRPSs), which assemble siderophores and lipopeptides. Our analysis also revealed that lipopeptide production is confined to the Pseudomonas fluorescens lineage and shows a correlation between NRPS and taxonomic affiliation.
Article
Chemistry, Multidisciplinary
Kevin Van Holsbeeck, Baptiste Fischer, Simon Gonzalez, Charlene Gadais, Wim Versees, Jose C. Martins, Charlotte Martin, Alexandre Wohlkoenig, Jan Steyaert, Steven Ballet
Summary: RAS proteins play a crucial role in regulating intracellular signaling networks and mutations that stabilize their active state are associated with cancer development. The study investigated the potential of developing peptide mimetics to modulate RAS signaling by mimicking the complementarity-determining region 3 (CDR3) of the regulatory guanine nucleotide exchange factor (GEF) son of sevenless 1 (SOS1). Through optimization and conformational rigidification, CDR3 mimetics with half of the maximal activation potential of Nanobody14 (Nb14) were obtained, demonstrating the feasibility of modulating protein-protein interactions through structural mimicry of a paratope.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
M. Chandra Sekhar, Gabriele Pippia, Ivo Tanghe, Beatriz Martin-Garcia, Anastasia Rousaki, Peter Vandenabeele, Pieter Schiettecatte, Iwan Moreels, Pieter Geiregat
Summary: Transition metal dichalcogenides (TMDs) are promising nanostructured semiconductors for optoelectronics and photocatalysis. This study reveals that the carrier dynamics in monolayer TMDs are dominated by fast electron trapping, while multilayered TMDs are dominated by hole trapping. Sizable exciton red shifts are found in monolayer TMDs, which can be attributed to interactions with trapped electrons and lattice heating.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Carmelita Roda, Alessio Di Giacomo, Lucia Camila Tasende Rodriguez, M. Chandra Sekhar, Jari Leemans, Zeger Hens, Pieter Geiregat, Iwan Moreels
Summary: We synthesized CdSe/CdS nanoplatelets with 3.5 monolayers, which exhibit saturated blue emission and high photoluminescence quantum efficiency (PL QE) up to 55%. Compared to core-only nanoplatelets, the PL intensity decays exponentially due to suppressed deep trapping and delayed emission. Both core-only and core/crown nanoplatelets show biexciton-mediated optical gain between 470 and 510 nm, with higher gain coefficients in crowned nanoplatelets. However, the gain lifetimes are limited to 40 ps due to residual ultrafast trapping and higher exciton densities at threshold. These findings provide guidelines for optimizing CdSe nanoplatelets for lighting and light-amplification applications.
Article
Nanoscience & Nanotechnology
Matteo Barelli, Cynthia Vidal, Sergio Fiorito, Alina Myslovska, Dimitrie Cielecki, Vincenzo Aglieri, Iwan Moreels, Riccardo Sapienza, Francesco Di Stasio
Summary: This study demonstrates the controlled placement of colloidal semiconductor nanocrystals onto planar surfaces by patterning nanohole arrays in a PMMA thin film and trapping the nanocrystals into the holes. The resulting arrays contain hundreds of single-photon emitters, providing a feasible, fast, and practical method for the fabrication of nanodevices based on colloidal semiconductor nanocrystals, such as single-photon-emitting LEDs.
Article
Chemistry, Physical
Fadi AL-Shnani, Chandra Sekhar Mutyala, Carmelita Roda, Iwan Moreels
Summary: In this work, a synthesis method for 3.5 monolayerCdTe nanoplatelets with controlled lateral dimensions was developed. The chemical reactivity of the tellurium precursor was found to play a crucial role in achieving this. The effects of additives, such as oleic acid, acetic acid, and water, on the nanoplatelet lateral dimensions and optical properties were investigated. An optimal combination of additives was obtained, resulting in a minimal nanoplatelet area. After exposure to cadmium propionate, nanoplatelets with a fluorescence quantum efficiency of up to 12% were obtained.
CHEMISTRY OF MATERIALS
(2023)
Review
Chemistry, Physical
Joanna Dehnel, Adi Harchol, Yahel Barak, Itay Meir, Faris Horani, Arthur Shapiro, Rotem Strassberg, Celso de Mello Donega, Hilmi Volkan Demir, Daniel R. Gamelin, Kusha Sharma, Efrat Lifshitz
Summary: Incorporating magnetic ions into semiconductor nanocrystals is a promising research field for manipulating spin-related properties. Various host materials and magnetic ions have been studied, and the impact of nanostructure engineering and ion selection in carrier-magnetic ion interactions is emphasized. The use of optically detected magnetic resonance spectroscopy provides valuable insights into the spin dynamics and physical parameters of the carrier-magnetic ion interactions.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Nanoscience & Nanotechnology
Ivo Tanghe, Margarita Samoli, Isabella Wagner, Servet Ataberk Cayan, Ali Hossain Khan, Kai Chen, Justin Hodgkiss, Iwan Moreels, Dries Van Thourhout, Zeger Hens, Pieter Geiregat
Summary: Colloidal quantum dots have been investigated for low-cost light emission and lasing for nearly two decades. Bulk nanocrystals of CdS show exceptional material gain, low thresholds, and long lifetimes. The findings are attributed to a strong bandgap renormalization effect. Additionally, broadband amplified spontaneous emission and lasing were demonstrated under quasi-continuous-wave conditions.
NATURE NANOTECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Gabriele Pippia, Diem Van Hamme, Beatriz Martin-Garcia, Mirko Prato, Iwan Moreels
Summary: This study focused on the synthesis of tungsten disulfide (WS2) monolayers using a colloidal method, with detailed investigation on the impact of synthesis parameters. Nanosheets with monolayer characteristics were successfully obtained after optimization, confirmed by Raman spectroscopy.
Article
Chemistry, Physical
Serena Busatto, Celso de Mello Donega
Summary: Research on magic-size colloidal nanostructures is still in its infancy, and many fundamental questions remain unanswered. The formation mechanisms and enhanced stability of these structures are complex and not yet understood. Further experimental investigations are needed to unravel these mysteries.
