Article
Chemistry, Physical
Natalia Przybylska, Malgorzata Sliwinska-Bartkowiak, Mikolaj Koscinski, Konrad Rotnicki, Marek Bartkowiak, Stefan Jurga
Summary: This study investigated the properties of water solution of ciprofloxacin confined in single wall carbon nanotubes, examining the influence of nanotube size and structure on interactions with the drug. Raman spectroscopy of the carbon nanotubes revealed a correlation between their amorphousness and semiconductor properties, while FT-IR spectroscopy was used to identify the structure of the confined ciprofloxacin and determine which vibrations of functional groups in the ciprofloxacin molecule were suppressed by confinement.
JOURNAL OF MOLECULAR LIQUIDS
(2021)
Article
Chemistry, Physical
Mourad Berd, Kamal Moussi, Youcef Aouabdia, Lotfi Benchallal, Ghiles Chahi, Badis Kahouadji
Summary: This study investigated the treatment of single-walled carbon nanotubes with strong HClO4 acid through experimental and computational analysis, showing significant changes in the behavior of metallic nanotubes and their conversion to semiconductors. The DFT calculations confirmed the experimental results by revealing the generation of an energy gap in the electronic structure of metallic carbon nanotubes due to the adsorption of chlorine atoms.
CHEMICAL PHYSICS LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Quanfeng He, Lanping Zeng, Lianhuan Han, Matthew M. Sartin, Juan Peng, Jian-Feng Li, Alexander Oleinick, Irina Svir, Christian Amatore, Zhong-Qun Tian, Dongping Zhan
Summary: Studies have shown that the adsorption of atomic hydrogen on single layer graphene can effectively store hydrogen and is suitable for solutions involving hydrogen fuel cells for vehicles. Utilizing a Pt-electrocatalyzed spillover-surface diffusion-chemisorption mechanism, hydrogenation of graphene can be carried out under mild conditions, demonstrating high storage capacity and stability.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Multidisciplinary
Emmanuel Picheau, Anthony Impellizzeri, Dmitry Rybkovskiy, Maxime Bayle, Jean-Yves Mevellec, Ferdinand Hof, Hassan Saadaoui, Laure Noe, Abraao Cefas Torres Dias, Jean-Luc Duvail, Marc Monthioux, Bernard Humbert, Pascal Puech, Christopher P. Ewels, Alain Penicaue
Summary: Above a critical diameter, carbon nanotubes collapse into flattened forms, leading to unique Raman spectra changes. The presence of edge cavities and curvature changes near the edges activate a D band despite overall continuity in the structure. The differing perspectives of chemists and physicists on defects in carbon structures may lead to confusion for researchers in nanotechnologies.
Article
Spectroscopy
Yunxia Liu, Beilei Sun, Lucie Tajcmanova, Chao Liu, Jie Wu
Summary: This study collected fly ash samples from seven typical power plants in Shanxi province, China, to explore the effect of carbon residue structures on their burnout characteristic. The results showed that the structure of carbon residues in the fly ash has a significant impact on burnout characteristic, with more ordered structures in fly ash from circulating fluidized bed (CFB) power plants suppressing burnout and leading to an increase in loss on ignition (LOI) content, while less ordered structures in fly ash from pulverized coal boilers (PC) promoting burnout and resulting in a reduction of LOI content.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2022)
Article
Materials Science, Multidisciplinary
Zhichen Yan, Shuangyue Wang, Xianjue Chen, Geedhika K. Poduval, John A. Stride
Summary: Chemical vapor deposition (CVD) shows great potential in large-scale production of graphene films. A new method has been developed to directly grow graphene films on crystalline silicon wafers with a 300 nm oxide layer using a seeded-CVD growth approach. The use of methane as feedstock and optimized graphene seeds has improved the film formation, which consists of graphene layers formed by the coalescence of expanding graphene seeds according to SEM, X-ray photoelectron and Raman spectroscopies. The films also exhibit regions of single graphene crystallites resulting from lateral growth of the seeds. Moreover, the unilateral conductivity of the graphene films suggests potential application in device fabrication due to the presence of graphene nanoribbons.
JOURNAL OF MATERIALS SCIENCE
(2023)
Article
Chemistry, Physical
Thiago A. Moura, Wellington Q. Neves, Rafael S. Alencar, Y. A. Kim, M. Endo, Thiago L. Vasconcelos, Deyse G. Costa, Graziani Candiotto, Rodrigo B. Capaz, Paulo T. Araujo, Antonio G. Souza Filho, Alexandre R. Paschoal
Summary: The unique electronic and vibrational properties of linear carbon chains (LCCs) have attracted attention recently. Raman spectroscopy has been widely used to identify LCC and study its properties. This study investigates the optical resonance window of LCCs encapsulated by multi-walled carbon nanotubes (MWCNTs) and a Raman signature assigned to the LCC's longitudinal acoustic phonon mode. First-principles calculations support the conclusions.
Article
Chemistry, Physical
Maksiem Erkens, Sofie Cambre, Emmanuel Flahaut, Frederic Fossard, Annick Loiseau, Wim Wenseleers
Summary: The study shows that even mild ultrasonication can affect the structure of double-wall carbon nanotubes, leading to the extraction of inner single-wall carbon nanotubes. After strict processing steps, the extracted SWCNTs increase in density, with ultrasonication resulting in the formation of single-wall carbon nanotubes.
Article
Chemistry, Physical
Valentina Villari, Massimiliano Gaeta, Alessandro D'Urso, Norberto Micali
Summary: The functionalization of carbon dots with dyes through supramolecular interactions can provide desired optical properties. In this study, supramolecular complexes formed spontaneously in water medium between an anionic meso-tetrakis(4-sulfonatophenyl) porphyrin and three different fluorescent carbon nanodots were investigated. The results showed that the formation of porphyrin/carbon dot adducts is favored by high surface charge of the nanodots, and the resulting emission properties depend on the surface precursor. These nanomaterials show fluorescence quenching, making them potential candidates for energy conversion or sensor applications.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2022)
Article
Polymer Science
Guillaume Pillet, Pascal Puech, Sebastien Moyano, Frederic Neumayer, Wolfgang Bacsa
Summary: The conductivity of thermoplastic polymers can be effectively enhanced by incorporating carbon nanotubes on the surface. Multiwall carbon nanotubes thin films were transferred onto the polymer surface to form composite layers with electrical conductivity up to 8 S/cm, showing variations at 2.8 vol% of nanotubes. The distribution and quantity of nanotubes were studied using transmission electron microscopy and optical transmission measurements.
Article
Engineering, Manufacturing
Ayaka Aoki, Toshio Ogasawara, Takuya Aoki, Yuichi Ishida, Yoshinobu Shimamura, Yoku Inoue
Summary: This study utilized polarized Raman spectroscopy to assess the strain in aligned multi-walled carbon nanotube/epoxy composites, aiming to clarify the effective elastic modulus of the carbon nanotubes. The Raman shift rate of the G' band of the carbon nanotubes was found to be 18.84 cm(-1)/% corresponding to the tensile strain of the composite specimen. Through Mori-Tanaka theory and consideration of the three-dimensional orientation distribution of the carbon nanotubes, the effective elastic modulus of the carbon nanotubes was estimated to be 400 GPa. The results demonstrated the utility of Raman spectroscopy in experimentally evaluating the effective elastic modulus of multi-walled carbon nanotubes in composites.
COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
(2023)
Article
Chemistry, Multidisciplinary
Samuel Faucher, Matthias Kuehne, Hananeh Oliaei, Rahul Prasanna Misra, Sylvia Xin Li, Narayana R. Aluru, Michael S. Strano
Summary: Recent measurements have shown that fluids under extreme confinement, such as water in narrow carbon nanotubes, deviate significantly from theoretical descriptions. In this study, precise replicas of carbon nanotubes filled with water were generated and analyzed using Raman spectroscopy. The results revealed the presence of submicron vapor-like and liquid-like domains in partially filled nanodroplet states, and a Clausius-Clapeyron-type model was used to calculate the heats of condensation of water inside different diameter carbon nanotubes. The findings suggest the potential of molecular engineering of nanoconfined liquid/vapor interfaces for water treatment or membrane distillation.
Article
Chemistry, Physical
Xiaolong Bai, Dengmeng Song, Jiaojiao Wei, Dan Wang, Jun Li
Summary: In this study, metalloporphyrin modified carbon nanotubes were synthesized and used as catalyst supports, displaying excellent activity and stability for catalyzing the chemical fixation of CO2. The remarkable performance of ZnTImP-CP/CNTs is attributed to the synergy of the Lewis acid and base as well as the large specific surface area.
Article
Chemistry, Multidisciplinary
Maksiem Erkens, Dmitry Levshov, Wim Wenseleers, Han Li, Benjamin S. Flavel, Jeffrey A. Fagan, Valentin N. Popov, Marina Avramenko, Salome Forel, Emmanuel Flahaut, Sofie Cambre
Summary: The study investigates the synergetic effects in double-wall carbon nanotube (DWCNT) samples through absorption, fluorescence excitation, and resonant Raman scattering spectroscopy. The chirality-dependent shifts of the vibrational frequencies and transition energies of the inner and outer DWCNT walls are determined. The combined analysis of PLE and RRS results provides insights into the energy transfer within DWCNT structures and the specific combinations present in the samples.
Article
Chemistry, Multidisciplinary
Weili Cui, Lei Shi, Kecheng Cao, Ute Kaiser, Takeshi Saito, Paola Ayala, Thomas Pichler
Summary: Carbyne is a one-dimensional allotrope of carbon, which is stable when grown encapsulated in carbon nanotubes. By using isotopic labeling as a tuning mechanism, researchers were able to control its properties and achieve pioneering results with around 11.9% of C-13 labeling.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Physical
Juraj Jasik, Stanislav Valtera, Mykhailo Vaidulych, Muntaseer Bunian, Yu Lei, Avik Halder, Hana Tarabkova, Martin Jindra, Ladislav Kavan, Otakar Frank, Stephan Bartling, Stefan Vajda
Summary: The effects of composition and support on the catalytic activity and selectivity in the oxidative dehydrogenation of cyclohexene were investigated. The study found that ultra-nanocrystalline diamond supported clusters were highly active and mainly produced benzene, while some mixed clusters produced cyclohexadiene. TiO2-supported tetramers solely produced benzene without any combustion to CO2. The selectivity of zirconia-supported mixed CuPd clusters and monometallic Cu cluster differed significantly, with the former producing significant fractions of cyclohexadiene.
FARADAY DISCUSSIONS
(2023)
Article
Electrochemistry
M. Zlamalova, V. Mansfeldova, H. Tarabkova, H. Krysova, L. Kavan
Summary: By using atomic layer deposition, TiO2 thin films were prepared that can withstand thermal treatment without cracking at 450-500°C. Electrochemical impedance (Mott-Schottky) and Kelvin probe analyses showed that calcination caused a tens of meV change in the work function of the film. In contrast, the work function of ALD-SnO2 increased by hundreds of meV after the same heat treatment. The calcined ALD-SnO2 film exhibited a work function of about 0.3-0.4 eV higher than that of the cassiterite single-crystal electrode, and it was photoelectrochemically inactive.
JOURNAL OF SOLID STATE ELECTROCHEMISTRY
(2023)
Article
Materials Science, Multidisciplinary
Marketa Zukalova, Monika Vinarcikova, Barbora Pitna Laskova, Ladislav Kavan
Summary: A facile method of preparing a TiO2 top layer on the sulfur/carbon cathode in a Li-sulfur battery is presented. The layer significantly improves the initial charge capacity of composite cathodes. The effect of the TiO2 top layer is evaluated on different types of sulfur composite cathodes with carbonaceous additives, and the electrochemical performance is studied through various tests.
MATERIALS CHEMISTRY AND PHYSICS
(2023)
Article
Nanoscience & Nanotechnology
Zoran M. Markovic, Milica D. Budimir, Martin Danko, Dusan D. Milivojevic, Pavel Kubat, Danica Z. Zmejkoski, Vladimir B. Pavlovic, Marija M. Mojsin, Milena J. Stevanovic, Biljana M. Todorovic Markovic
Summary: In this study, carbon quantum dots were prepared from o-phenylenediamine dissolved in toluene by a solvothermal route, and then encapsulated into polyurethane films by a swelling-encapsulation-shrink method. The precursor was found to have a significant influence on the structural, chemical, and optical properties. Antibacterial and cytotoxicity tests showed low antibacterial potential and dark cytotoxicity, while cellular uptake experiments confirmed the potential use of these dots as bioimaging probes.
BEILSTEIN JOURNAL OF NANOTECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Alvaro Rodriguez, Javier Varillas, Golam Haider, Martin Kalbac, Otakar Frank
Summary: We investigate the intrinsic strain in twisted MoS2/MoSe2 heterobilayers and find that small twist angles result in atomic reconstructions, large moire periodicities, and high local strains. The formation of moire superlattices is assisted by stacking domain reconstructions, leading to a complex strain distribution. Larger twist angles hinder lattice reconstruction and result in moire patterns with small periodicities and negligible strains.
Review
Chemistry, Inorganic & Nuclear
Kaplan Kirakci, Michael A. Shestopalov, Kamil Lang
Summary: Over the past decades, the luminescent octahedral molybdenum, tungsten, and rhenium cluster complexes with the general formula [{M6Li8}La6]n have gained significant attention for their potential applications in photofunctional materials design. These complexes exhibit red phosphorescence with high quantum yields, sensitivity to oxygen, and production of singlet oxygen, O2(1Dg). The wide range of ligands allows for precise tuning of their physico-chemical, photophysical, and biological properties for various applications such as photodynamic therapy and photoinactivation of bacteria.
COORDINATION CHEMISTRY REVIEWS
(2023)
Article
Chemistry, Physical
Antonios Michail, Dimitris Anestopoulos, Nikos Delikoukos, Spyridon Grammatikopoulos, Sotirios A. Tsirkas, Nektarios N. Lathiotakis, Otakar Frank, Kyriakos Filintoglou, John Parthenios, Konstantinos Papagelis
Summary: Chemical vapor deposited WS2 monolayers are subjected to controlled pure biaxial tensile strain for the first time, achieving up to 0.7%. Trion and neutral exciton deformation potentials are found to be similar, indicating the potential impact of strain on carrier concentration and residual strain in WS2 samples. Density functional theory calculations support the experimental findings and provide insights into the electronic and phonon band structures in monolayer WS2 under strain.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Joanna E. Olszowka, Pavel Kubat, Jiri Dedecek, Edyta Tabor
Summary: Our luminescence studies demonstrate that the four cooperating aluminum atoms located at neighboring six-membered rings in the ferrierite framework can be easily distinguished. The presence of neighboring cobalt ions stabilized by the second ring effectively quenches luminescent zinc ions accommodated by one aluminum pair of the 6-MR ring. This quenching, occurring through energy transfer, enables estimation of the critical radius of zinc-cobalt interactions, providing direct evidence of the arrangement of the four aluminum atoms in the ferrierite framework.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Ghulam Abbas, Farjana J. Sonia, Martin Jindra, Jiri Cervenka, Martin Kalbac, Otakar Frank, Matej Velicky
Summary: Electrostatic gating using electrolytes is an effective method for controlling the electronic properties of atomically thin two-dimensional materials such as graphene. However, the relationship between the ionic type, size, concentration, and gating efficiency is complex. We conducted in situ Raman microspectroscopy combined with electrostatic gating using various concentrated aqueous electrolytes to understand these relationships. We found that the ionic type and concentration do not significantly affect the doping rate of graphene in the high ionic strength limit of 3-15 M, and a large proportion of the applied voltage contributes to the Fermi level shift in concentrated electrolytes. We provide a practical overview of the doping efficiency for different gating systems.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Inorganic & Nuclear
Bela Urban, David Dunlop, Robert Gyepes, Pavel Kubat, Kamil Lang, Michal Horacek, Jiri Pinkas, Ludmila Simkova, Martin Lamac
Summary: Neutral zirconocene complexes were synthesized and converted to their cationic counterparts by chloride abstraction. The cationic complexes exhibited enhanced luminescence properties. The structures of the complexes were characterized by X-ray diffraction, their electrochemistry was investigated by cyclic voltammetry, and their photophysical properties were studied with quantum-chemical calculations.
Article
Chemistry, Inorganic & Nuclear
Regis Guegan, Xiaoxue Cheng, Xiang Huang, Zuzana Nemeckova, Michaela Kubanova, Jaroslav Zelenka, Tomas Ruml, Fabien Grasset, Yoshiyuki Sugahara, Kamil Lang, Kaplan Kirakci
Summary: The photoinactivation of pathogenic bacteria using materials generating reactive oxygen species upon exposure to visible light can overcome the challenge of multidrug-resistant microbial pathogens. A nanocomposite material consisting of graphene oxide sheets adorned with nanoaggregates of octahedral molybdenum cluster complexes has been developed. The electrostatic interaction and close cohesion between the components in aqueous medium contributed to the potent antibacterial effect against Staphylococcus aureus upon illumination with blue light. The photoinduced electron transfer from the nanoaggregates to the graphene oxide sheets triggers the generation of reactive oxygen species, making graphene oxide and light-harvesting octahedral molybdenum cluster complexes promising for effective antibacterial strategies.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Inorganic & Nuclear
Regis Guegan, Xiaoxue Cheng, Xiang Huang, Zuzana Nemeckova, Michaela Kubanova, Jaroslav Zelenka, Tomas Ruml, Fabien Grasset, Yoshiyuki Sugahara, Kamil Lang, Kaplan Kirakci
Summary: The emergence of multidrug-resistant microbial pathogens poses a significant threat to effective antibiotic therapy. Photoinactivation using materials generating reactive oxygen species upon exposure to visible light can overcome this challenge by targeting vital components of living cells, reducing the likelihood of resistance development.
INORGANIC CHEMISTRY
(2023)
Article
Materials Science, Multidisciplinary
Alexis Verger, Gilles Dollo, Nolwenn Brandhonneur, Sophie Martinais, Stephane Cordier, Kamil Lang, Maria Amela-Cortes, Kaplan Kirakci
Summary: Efficient intracellular uptake of the photosensitizer is necessary for photodynamic applications. In this study, PEGylated poly(lactic-co-glycolic acid) nanoparticles loaded with an octahedral molybdenum cluster complex were prepared. The encapsulated complexes maintained their photocytotoxic activity and exhibited high colloidal stability, making them potential agents for photodynamic therapy.
MATERIALS ADVANCES
(2023)
Article
Materials Science, Multidisciplinary
Kaplan Kirakci, Robert Pola, Marina Rodrigues Tavares, Michal Pechar, Tomas Pribyl, Ivana Krizova, Jaroslav Zelenka, Tomas Ruml, Tomas Etrych, Kamil Lang
Summary: This study successfully conjugated octahedral molybdenum clusters with organic polymers, resulting in a highly stable nanosized conjugate. The conjugate demonstrated the ability to photosensitize the production of singlet oxygen without being toxic to cells. It also showed potential as a radiosensitizer upon X-ray irradiation. This research provides a promising therapeutic tool for photo/radiodynamic applications.
MATERIALS ADVANCES
(2023)
