Article
Chemistry, Multidisciplinary
Linda Sistemich, Phillip Galonska, Jan Stegemann, Julia Ackermann, Sebastian Kruss
Summary: Single-walled carbon nanotubes (SWCNTs) are versatile building blocks for biosensors that can respond to analytes by a change in fluorescence. However, intensity-based signals are easily affected by external factors. In this study, we demonstrate the use of fluorescence lifetime imaging microscopy (FLIM) to overcome this issue and utilize SWCNT-based sensors for detecting dopamine.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Nanoscience & Nanotechnology
Jiangcai Wang, Huan Liu, Xiangmin Hu, Yuanshuang Liu, Dameng Liu
Summary: This study directly observed atomic-scale defect-accelerated energy transfer (ET) in MoS2/hBN/WS2 heterostructures using fluorescence lifetime imaging microscopy. By controlling defect density, the ET rate and time could be regulated.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Optics
Pavel Peterka, Artur O. Slobodeniuk, Tomas Novotny, Pawan Suthar, Miroslav Bartos, Frantisek Trojanek, Petr Maly, Martin Kozak
Summary: We experimentally investigate nonperturbative high harmonic generation (HHG) in monolayer MoS2 in the ultraviolet spectral region driven by mid-infrared light. The HHG is influenced by pre-excitation of the monolayer using resonant and near-resonant pulses. The presence of pre-excited carriers suppresses HHG due to ultrafast dephasing caused by electron-electron scattering. Near-resonant excitation with photon energy below the exciton transition shows a fast component in the suppression of HHG yield, which is a consequence of momentum scattering at carriers excited by two-photon transition.
Article
Spectroscopy
Anchal Sharma, Harshita Rastogi, Kalyan Sundar Ghosh
Summary: The chaperone activity of human alpha A-crystallin (HAA) against aggregation of human gamma D-crystallin (HGD) was enhanced by gold nanoparticles (AuNPs), and the interactions between HAA and AuNPs were studied using fluorescence and circular dichroism spectroscopic techniques.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2022)
Review
Chemistry, Multidisciplinary
Jianjian Zhang, Lulu Ning, Ziling Zeng, Kanyi Pu
Summary: Photoacoustic imaging in the NIR-II window offers deeper penetration and lower background noise compared to the NIR-I window. Contrast agents can be used to visualize biological processes at greater depths, and further development of activatable probes shows promise for biomarker detection in biomedical research. Potential challenges and prospects in the field of NIR-II PAI contrast agents are also discussed.
TRENDS IN CHEMISTRY
(2021)
Article
Chemistry, Physical
Ana-Maria Craciun, Laurentiu Susu, Monica Baia
Summary: The intrinsic photoluminescence properties of gold nanorods coated with gelatin were studied using innovative fluorescence spectroscopy combined with fluorescence lifetime imaging microscopy. The study revealed interesting aspect ratio-dependent two-photon excited photoluminescence emission, with a lifetime of around 100 ps. The effect of laser excitation power and wavelength on the photoluminescence performance was evaluated, highlighting the potential application of gelatin-coated gold nanorods as contrast agents for label-free two-photon fluorescence imaging.
JOURNAL OF MOLECULAR STRUCTURE
(2021)
Article
Chemistry, Multidisciplinary
Ho Jin Jang, Jun Yeob Lee
Summary: The device lifetime of exciplex organic light-emitting diodes was extended by almost four times through control of the p-type material content by mimicking the host-dopant system. The major pathway to stabilize the exciplex devices was suppression of triplet exciton loss by strong intermolecular interaction and concentration quenching. dispersing p-type material in the bipolar n-type material was effective to elongate the device lifetime of the exciplex based organic light-emitting diodes.
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
(2021)
Article
Chemistry, Physical
Zhi-Di Li, Hao-Sen Kang, Ming-Yang Long, Jing-Chuan Liu, Tao Zhou, Dan Zhu, Liang Ma, Si-Jing Ding, Li Zhou
Summary: In this study, structure-adjustable Au nanodumbbells were prepared and used for plasmon-enhanced surface-enhanced Raman scattering (SERS) and second-harmonic generation (SHG). The results showed that the Au nanodumbbells exhibited better performance in enhancing Raman signals compared to Au nanorods, and double-resonantly enhanced SHG was achieved by precisely adjusting the end size of the nanodumbbells.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Multidisciplinary
Alexandr Popov, Elena Orlovskaya, Artem Shaidulin, Ekaterina Vagapova, Elena Timofeeva, Leonid Dolgov, Lyudmila Iskhakova, Oleg Uvarov, Grigoriy Novikov, Mihkel Rahn, Aile Tamm, Alexander Vanetsev, Stanislav Fedorenko, Svetlana Eliseeva, Stephane Petoud, Yurii Orlovskii
Summary: Stable aqueous colloidal solutions of Nd3+: LaF3 single-phase nanoparticles with well-crystallized structure were synthesized using a hydrothermal method involving microwave-assisted heating. Two series of nanoparticles with different activator concentrations were prepared, and the fluorescence kinetics revealed luminescence quenching associated with Nd-Nd self-quenching and Nd-OH quenching. The developed method allows for determining the spontaneous radiative lifetime of the dopant ion's excited state, considering the contribution of luminescence quenching by impurity OH- acceptors.
Article
Chemistry, Physical
Ulugbek Barotov, Megan D. Klein, Lili Wang, Moungi G. Bawendi
Summary: The study focused on designing a novel J-aggregate system with high extinction coefficient, high QY, and short lifetime through a bottom-up approach. By selecting a J-aggregating cyanine chromophore and rigidifying its backbone, the researchers achieved highly emissive J-aggregates with strong absorbance and fluorescence properties at room temperature. The results have implications for the development of a new generation of organic fluorophores combining high speed, high QY, and solution processing.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Multidisciplinary
Ming-Yu Wu, Jong-Kai Leung, Chuen Kam, Tsu Yu Chou, Jia-Li Wang, Xueqian Zhao, Shun Feng, Sijie Chen
Summary: This study developed a near-infrared fluorescent probe named TBTCP for real-time imaging of phagocytosis. TBTCP could selectively label the cell plasma membrane and report the cell membrane statuses and macrophage phagocytosis through fluorescence lifetime changes. It provides a functional tool to study phagocytic function-related diseases.
SCIENCE CHINA-CHEMISTRY
(2022)
Article
Biochemistry & Molecular Biology
Sipun Sethi, Tankadhar Behera, Sumit Mohapatra, Bhawani Prasad Bag, Nabakrushna Behera
Summary: The interaction aspects of uranyl(VI) complexes and the ONNO-donor ligand with bovine serum albumin (BSA) were investigated using fluorescence spectroscopy and computational insights. It was observed that under optimal physiological conditions, the fluorescence intensity of BSA significantly decreased upon interaction with both the uranyl(VI) complexes and the ligand. The mechanism of interaction between the uranyl(VI) complex and BSA was examined, and various parameters such as binding affinity and fluorescence lifetime decay profile were determined.
JOURNAL OF INORGANIC BIOCHEMISTRY
(2023)
Article
Engineering, Environmental
Adrian Monteleone, Folker Wenzel, Heinz Langhals, Daniel Dietrich
Summary: The FLIM method was tested for identification and characterization of six types of plastics, showing significant differentiation in 94.55% of the comparisons. Results suggest that FLIM has the potential for sub-micrometer plastic characterization and allows for visual 3D-sectioning of samples, which could be important for identifying and characterizing plastics in tissue and environmental samples.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2021)
Article
Biochemical Research Methods
P. Wang, F. Hecht, G. Ossato, S. Tille, S. E. Fraser, J. A. Junge
Summary: Fluorescence lifetime imaging microscopy (FLIM) with phasor analysis allows for easy visualization and analysis of fluorophores' lifetimes, but typically suffers from low photon budgets leading to poor signal to noise ratios. Traditional median filters used in phasor analysis degrade high spatial frequency FLIM information, especially edges and puncta. A new filtering strategy using complex wavelet filtering and Anscombe transform preserves fine structures and accurate lifetimes in photon starved FLIM imaging, outperforming median filters and enabling FLIM imaging with lower laser power and faster imaging speed.
BIOMEDICAL OPTICS EXPRESS
(2021)
Article
Environmental Sciences
Juan Liu, Ruiya Zhou, Xu Zhang
Summary: The study revealed that the binding of calcium ion and magnesium ion to terrestrial chromophoric dissolved organic matter results in fluorescence quenching. Calcium ion exhibited a higher efficiency of fluorescence quenching compared to magnesium ion. Additionally, high concentrations of calcium ion and magnesium ion accelerated the fluorescence decay of CDOM.
Article
Nanoscience & Nanotechnology
Adar Levi, Lior Verbitsky, Nir Waiskopf, Uri Banin
Summary: Coating with sulfide can enhance one-electron processes while inhibiting two-electron reduction processes, showing a double-edged sword effect. It relieves the hole extraction bottleneck from the semiconductor segment but also poisons the metal domain, restricting its reductive capacity for two-electron processes requiring a chemisorption step on the metal surface. This highlights the importance of surface properties for the photocatalytic action of hybrid nanoparticle systems.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Chemistry, Multidisciplinary
Orian Elimelech, Omer Aviv, Meirav Oded, Xiaogang Peng, Daniel Harries, Uri Banin
Summary: The surface ligands of semiconductor nanocrystals play a crucial role in their colloidal stability and physicochemical properties. In this study, the impact of the ligand chain backbone structure on the thermodynamics of the exchange reaction for oleate coated CdSe NCs was investigated. The results showed that branched ligands have lower exothermicity and entropy loss compared to linear ligands, due to steric hindrance in ligand packing. The findings suggest that a short, branched ligand with a short branching group located toward the middle of the ligand chain is the most entropic ligand.
Article
Chemistry, Multidisciplinary
Yossef E. Panfil, Jiabin Cui, Somnath Koley, Uri Banin
Summary: Colloidal quantum dots (CQDs) are essential components in modern optoelectronic devices. Recent development of coupled colloidal quantum dots molecules (CQDM) allows investigation of the interaction between charge carriers in different CQDs. Experimental and computational study reveals the complex emission spectra and coupled behavior in CQDM, which is significant for quantum technology and sensing applications based on CQDM.
Article
Chemistry, Multidisciplinary
Einav Scharf, Franziska Krieg, Orian Elimelech, Meirav Oded, Adar Levi, Dmitry N. Dirin, Maksym Kovalenko, Uri Banin
Summary: This study investigates the effects of different stabilizing surface ligands on the kinetics of the cross-anion exchange reaction and finds that zwitterionic ligands can slow down the process, offering improved stability and enhanced solubility.
Article
Chemistry, Physical
Lior Verbitsky, Dipti Jasrasaria, Uri Banin, Eran Rabani
Summary: This study explores the structural, electronic, and optical properties of CdSe/CdS core-shell colloidal quantum dot molecules using atomistic approaches. The strain profile maps of free-standing colloidal dimers show negligible additional strain resulting from attachment. The electronic properties are described using a semiempirical pseudopotential model and the Bethe-Salpeter equation. The study analyzes the effects of strain, hybridization, quantum confinement, and electron-hole binding energies on the optical properties, and also investigates the influence of the dimensions of the neck and the shell thickness.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Lior Asor, Jing Liu, Shuting Xiang, Nir Tessler, Anatoly I. Frenkel, Uri Banin
Summary: Doped heavy metal-free III-V semiconductor nanocrystal quantum dots (QDs) have attracted great interest for both their fundamental doping characteristics and their applicability in p-n homojunction devices. In this study, p-type doping of InAs NCs was achieved through the use of Zn, allowing for control over the charge carrier type in InAs QDs field effect transistors. X-ray absorption spectroscopy analysis confirmed substitutional doping by Zn2+ replacing In3+. Surface passivation by Zn was also observed, leading to enhanced near infrared photoluminescence. This research paves the way for the fabrication of optoelectronic devices active in the short-wave infrared region using heavy-metal free nanocrystal building blocks.
ADVANCED MATERIALS
(2023)
Review
Chemistry, Multidisciplinary
Yuval Ben-Shahar, David Stone, Uri Banin
Summary: Nanochemistry offers powerful synthetic tools for combining different materials on a single nanostructure, allowing for customization of their properties for various functionalities. This review focuses on the progress in semiconductor-metal hybrid nanoparticles (HNPs), particularly metal-chalcogenides-metal combined systems. The synthesis principles and various hybrid architectures of HNPs are discussed, with an emphasis on emergent characteristics and the light-induced charge-separation effect. The potential applications of HNPs as photocatalysts in solar-to-fuel conversion, photopolymerization, 3D printing, and chemical and biomedical uses are explored.
Article
Chemistry, Multidisciplinary
Orian Elimelech, Meirav Oded, Daniel Harries, Uri Banin
Summary: Binary compositions of surface ligands significantly improve the colloidal stability and fluorescence quantum yield of nanocrystals (NCs). In this study, the thermodynamics of a ligand exchange reaction of CdSe NCs with alkylthiol mixtures were investigated using isothermal titration calorimetry (ITC). It was found that the interligand interactions determine the clustering patterns of the ligand shell structure. This work provides fundamental insights for the design of smart surfaces in NC-based applications.
Editorial Material
Chemistry, Multidisciplinary
Younan Xia, Qian Chen, Uri Banin
Article
Multidisciplinary Sciences
Bokang Hou, Michael Thoss, Uri Banin, Eran Rabani
Summary: Electron transfer is a fundamental process, and researchers have demonstrated how to control the transition from nonadiabatic to adiabatic electron transfer in colloidal quantum dot molecules. By changing the neck dimensions and/or quantum dot sizes, the electronic coupling can be tuned, leading to coherent electron transfer even at high temperatures. The study also identifies the modes that strongly influence the charge transfer dynamics.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Tom Naor, Shira Gigi, Nir Waiskopf, Gila Jacobi, Sivan Shoshani, Doron Kam, Shlomo Magdassi, Ehud Banin, Uri Banin
Summary: This study highlights the importance and potential applications of nanocomposites. The use of colloidal semiconductor nanocrystals as fillers provides catalytic, mechanical, photocatalytic, and antimicrobial properties in polymer composites. Different fabrication methods can yield hydrogels with complex architectures.
Article
Chemistry, Multidisciplinary
Nadav Frenkel, Einav Scharf, Gur Lubin, Adar Levi, Yossef E. Panfil, Yonatan Ossia, Josep Planelles, Juan I. Climente, Uri Banin, Dan Oron
Summary: Coupled colloidal quantum dot molecules (CQDMs) are a novel type of nanomaterials that have two coupled emission centers, introducing additional degrees of freedom for designing quantum-dot-based technologies. However, the properties of multiply excited states in these CQDMs cannot be fully resolved by existing spectroscopic techniques. In this study, an extension of Heralded Spectroscopy is introduced to resolve the different biexciton species in the prototypical CdSe/CdS CQDM system, uncovering the coexistence and interplay of two distinct biexciton species.
Article
Chemistry, Physical
Yonatan Ossia, Adar Levi, Yossef E. Panfil, Somnath Koley, Einav Scharf, Nadav Chefetz, Sergei Remennik, Atzmon Vakahi, Uri Banin
Summary: Current quantum dot emitters are limited in their ability to tune color over a small spectral range without losing intensity. However, by utilizing quantum dot molecules with two coupled emission centers, reversible emission color switching without intensity loss can be achieved on a single-particle level. This breakthrough has the potential to enable sensitive field sensing and the development of color-switchable devices.
Article
Chemistry, Multidisciplinary
Shalaka Varshney, Meirav Oded, Sergei Remennik, Vitaly Gutkin, Uri Banin
Summary: Aluminum nanocrystals are a promising alternative to silver and gold for various applications. This research presents two wet-chemical colloidal approaches for surface coating of Al nanocrystals, which can control the surface chemistry and oxide thickness. By manipulating the surface chemistry, this research promotes the utilization of Al nanocrystals in diverse applications.
Article
Materials Science, Multidisciplinary
Somnath Koley, Jiabin Cui, Yossef. E. Panfil, Yonatan Ossia, Adar Levi, Einav Scharf, Lior Verbitsky, Uri Banin
Summary: The charge redistribution upon optical excitation of various necked homodimer colloidal quantum dot molecules (CQDMs) is investigated using single-particle emission spectroscopy. By tuning the hybridization of the electron wavefunctions at a fixed center-to-center distance through controlling the neck girth, we reveal two coupling limits: weak-coupling regime and strong-coupling regime. The emitted photons from CQDMs in the weak-coupling regime show high bunching while the antibunching is regained at the strong-coupling regime.
