OPEN Repository

Welcome to OPEN - the Repository of Open Scientific Publications, run by the Interdisciplinary Centre for Mathematical and Computational Modelling, University of Warsaw, previously operating as the CeON Repository. The Repository enables Polish researchers from all fields to openly share their articles, books, conference materials, reports, doctoral theses, and other scientific texts.

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PEGylated Network Nanostructured by Gold Nanoparticles for Electrochemical Sensing of Aromatic Redox and Nonredox Analytes
(American Chemical Society, 2024) Swiech, Olga; Majdecki, Maciej; Bilewicz, Renata; Faculty of Chemistry, University of Warsaw; Institute of Organic Chemistry, Polish Academy of Science
We present the design, tailoring, and physicochemical properties of a multicomponent polyethylene glycol (PEG)-based polymer doped with spherical nanoparticles modified with a lipoic acid derivative of cyclodextrin and its application for the electrochemical sensing of a ferrocene derivative and ibuprofen at low concentrations. Each of the components of this hybrid material has specific properties that can be useful for the preparation of sensors characterized by high selectivity and a low detection limit. Electrochemical studies have previously shown that the cyclodextrin derivative with an aromatic triazole linker in the structure enhances binding of the analyte, ensuring its preconcentration on the electrode and, therefore, enabling improvement of the sensor detection limit. On the other hand, the introduction of evenly dispersed spherical gold nanoparticles in the polymer matrix increases the conductivity of the film and enhances the analytical signal. The third component─a biocompatible and easily wettable cross-linker, PEG─allows for uninterrupted diffusion within the polymer film. This significantly increases the analytical performance of the sensor, supports further improvement of the detection limit, and enables the determination of the analyte after saturation of cyclodextrin cavities (high concentration of analyte) based on its diffusion response. The designed hybrid material was used for the direct and indirect determination of aromatic analytes─ferrocene derivative and ibuprofen─with a very low detection limit.
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Aqueous Micellar Environment Impacts the Co-Catalyzed Phototransformation: A Case Study
(American Chemical Society, 2024) Wincenciuk, Aleksandra; Cmoch, Piotr; Giedyk, Maciej; Andersson, Martin P.; Gryko, Dorota; Institute of Organic Chemistry, Polish Academy of Sciences; Center for Integrative Petroleum Research, King Fahd University of Petroleum and Minerals, Kingdom of Saudi Arabia
In recent years, methodologies that rely on water as the reaction medium have gained considerable attention. The unique properties of micellar solutions were shown to improve the regio-, stereo-, and chemoselectivity of different transformations. Herein, we demonstrate that the aqueous environment is a suitable medium for a visible light driven cobalt-catalyzed reaction involving radical species. In this system, reduced vitamin B12 reacts with alkyl halides, generating radicals that are trapped by the lipophilic olefin present in the Stern layer. A series of NMR measurements and theoretical studies revealed the location of reaction components in the micellar system.
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Microwave-Mediated Synthesis of Lead-Free Cesium Titanium Bromide Double Perovskite: A Sustainable Approach
(American Chemical Society, 2024-02-02) Reyes-Francis, Emmanuel; Echeverría-Arrondo, Carlos; Esparza, Diego; López-Luke, Tzarara; Soto-Montero, Tatiana; Morales-Masis, Monica; Turren-Cruz, Silver-Hamill; Mora-Seró, Iván; Julián-López, Beatriz; Instituto de Investigación en Metalurgia y Materiales, Universidad Michoacana de San Nicolás de Hidalgo, Mexico.; Institute of Advanced Materials (INAM), Universitat Jaume I, Spain.; Unidad Académica de Ingeniería Eléctrica, Universidad Autónoma de Zacatecas, Zacatecas, Mexico.; MESA+ Institute for Nanotechnology, University of Twente, Enschede, The Netherlands; Department of Physical Chemistry, Polish Academy of Sciences, Warsaw, Poland
Theoretical studies have identified cesium titanium bromide (Cs2TiBr6), a vacancy-ordered double perovskite, as a promising lead-free and earth-abundant candidate to replace Pb-based perovskites in photovoltaics. Our research is focused on overcoming the limitations associated with the current Cs2TiBr6 syntheses, which often involve high-vacuum and high-temperature evaporation techniques, high-energy milling, or intricate multistep solution processes conducted under an inert atmosphere, constraints that hinder industrial scalability. This study presents a straightforward, low-energy, and scalable solution procedure using microwave radiation to induce the formation of highly crystalline Cs2TiBr6 in a polar solvent. This methodology, where the choice of the solvent plays a crucial role, not only reduces the energy costs associated with perovskite production but also imparts exceptional stability to the resulting solid, in comparison with previous reports. This is a critical prerequisite for any technological advancement. The low-defective material demonstrates unprecedented structural stability under various stimuli such as moisture, oxygen, elevated temperatures (over 130 °C), and continuous exposure to white light illumination. In summary, our study represents an important step forward in the efficient and cost-effective synthesis of Cs2TiBr6, offering a compelling solution for the development of eco-friendly, earth-abundant Pb-free perovskite materials.
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Regioisomerism vs Conformation: Impact of Molecular Design on the Emission Pathway in Organic Light-Emitting Device Emitters
(American Chemical Society, 2024) Govindharaj, Prasannamani; Wierzba, Aleksandra J.; Kęska, Karolina; Kochman, Michał A.; Wiosna-Sałyga, Gabriela; Kubas, Adam; Data, Przemysław; Lindner, Marcin; Faculty of Chemistry, Łódź University of Technology; Institute of Organic Chemistry, Polish Academy of Sciences; Institute of Physical Chemistry, Polish Academy of Sciences
Despite the design and proposal of several new structural motifs as thermally activated delayed fluorescent (TADF) emitters for organic light-emitting device (OLED) applications, the nature of their interaction with the host matrix in the emissive layer of the device and their influence on observed photophysical outputs remain unclear. To address this issue, we present, for the first time, the use of up to four regioisomers bearing a donor–acceptor–donor electronic structure based on the desymmetrized naphthalene benzimidazole scaffold, equipped with various electron-donating units and possessing distinguished conformational lability. Quantum chemical calculations allow us to identify the most favorable conformations adopted by the electron-rich groups across the entire pool of regioisomers. These conformations were then compared with conformational changes caused by the interaction of the emitter with the Zeonex and 4,4′-bis(N-carbazolyl)-1,1′-biphenyl (CBP) matrices, and the correlation with observed photophysics was monitored by UV–vis absorption and steady-state photoluminescence spectra, combined with time-resolved spectroscopic techniques. Importantly, a CBP matrix was found to have a significant impact on the conformational change of regioisomers, leading to unique TADF emission mechanisms that encompass dual emission and inversion of the singlet–triplet excited-state energies and result in the enhancement of TADF efficiency. As a proof of concept, regioisomers with optimal donor positions were utilized to fabricate an OLED, revealing, with the best-performing dye, an external quantum emission of 11.6%, accompanied by remarkable luminance (28,000 cd/m2). These observations lay the groundwork for a better understanding of the role of the host matrix. In the long term, this new knowledge can lead to predicting the influence of the host matrix and adopting the structure of the emitter in a way that allows the development of highly efficient and efficient OLEDs.
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Quadrupolar, Highly Polarized Dyes: Emission Dependence on Viscosity and Selective Mitochondria Staining
(American Chemical Society, 2024) Tasior, Mariusz; Vakuliuk, Olena; Wrzosek, Antoni; Vullev, Valentine I.; Szewczyk, Adam; Jacquemin, Denis; Gryko, Daniel T.; Institute of Organic Chemistry, Polish Academy of Sciences; Nencki Institute of Experimental Biology of Polish Academy of Sciences; University of California, Riverside, United States; Nantes Université, CNRS, CEISAM, France; Institut Universitaire de France (IUF)
Quadrupolar A-D-A-type 1,4-dihydropyrrolo[3,2-b]pyrroles (DHPPs) bearing pyridinium and quinolinium substituents emit in the 500–600 nm region. The enhancement of electronic communication between the electron-rich heterocyclic core and electron-deficient peripheral substituents turned out to be crucial for achieving emission enhancement in viscous media. DHPP bearing two 4-pyridinium substituents has optical brightness 34,000 in glycerol and only 700 in MeOH, as evidenced by measurements of the emission intensity and fluorescence lifetimes in a series of polar solvents. Such behavior makes it an excellent candidate for viscosity probes in fluorescence microscopy, as demonstrated by the fluorescence imaging of H9C2 cardiomyocytes.

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Start date: 2020 End date: 2024 Publisher: American Chemical Society
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