Optical data storage, information encryption, and security labeling technologies require materials that exhibit local, pronounced, and diverse modifications of their structure-dependent optical ...properties under external excitation. Herein, we propose and develop a novel platform relying on lead halide Ruddlesden–Popper phases that undergo a light-induced transition toward bulk perovskite and employ this phenomenon for the direct optical writing of multicolor patterns. This transition causes the weakening of quantum confinement and hence a reduction in the band gap. To extend the color gamut of photoluminescence, we use mixed-halide compositions that exhibit photoinduced halide segregation. The emission of the films can be tuned across the range of 450–600 nm. Laser irradiation provides high-resolution direct writing, whereas continuous-wave ultraviolet exposure is suitable for recording on larger scales. The luminescent images created on such films can be erased during the visualization process. This makes the proposed writing/erasing platform suitable for the manufacturing of optical data storage devices and light-erasable security labels.
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•We proposed a simple, cheap and rapid technique for fabrication of conductive Ni microstructures.•This technique is based on the method of laser-induced metal deposition.•Deep ...eutectic solvent with citric acid, choline chloride and nickel(II) chloride was used as a source of nickel.•The fabricated Ni microstructures exhibit good catalytic performance toward enzyme-free glucose sensing.
We carried out highly rapid laser-assisted deposition of conductive nickel microstructures on the surface of oxide glass from a deep eutectic solvent (DES). The implementation of deep eutectic solvents may significantly simplify the experimental procedure and drastically increase the deposition rate by more than 150 times in opposite to those observed for laser deposition from the aqueous solutions. It was shown that these structures exhibit promising electrocatalytic performance toward enzyme-free dopamine and acetaminophen sensing, including good sensitivity, low limit of detection and broad linear ranges.
The development of an algorithm to automate the process of measuring the magnetic properties of macroscopic objects in motion is an important problem in various industries, especially in ferrous ...metallurgy and at factories where ferrous scrap is a strategic raw material. The parameter that requires work control is the hidden mass fraction of a non-magnetic substance that is present in the ferromagnetic raw material. The solution to this problem has no prototypes. In our work, a simple measuring device and a mathematical algorithm for calculating the mass fraction of the non-magnetic fraction in a strongly magnetic matrix were developed. The device is an inductance coil, in which the angle of the electromagnet losses is related to the mass of the magnetic material moving the coil. The magnitude of the instantaneous values of the lost angle integral was compared with the result of weighing the object on scales. This allowed us to calculate the proportion of the magnetic and non-magnetic fractions. The use of this prototype is herein illustrated. The experimental results of the determination of the magnetic-fractional composition depending on the mass of scrap metal and its bulk and the magnetic characteristics are presented.
Microelectronics industry is growing fast and the rate of new devices' development increases every year. Therefore, methods for simple and high-precision metal coating on dielectrics are needed. ...Existing methods do not allow performing the high-precision metal deposition without using photomasks, while making a photomask for each prototype is a long and expensive process. One of the methods of maskless metal deposition is laser-induced chemical liquid-phase deposition (LCLD). In this work we show the effect of substrate surface type on a result of LCLD. Deposited copper structures were characterized by SEM, EDX and impedance spectroscopy. The results show that laser-induced copper deposition is highly affected by the surface being a homogeneous or composite material. It was found that the deposits with low resistivity and high quality metal localization mostly appear on the two-phase surfaces. In contrast, deposits on one-phase surfaces exhibited poor topology of copper material. Statistical modeling was involved to describe this phenomenon.
•Laser-assisted liquid-phase copper deposition is affected by substrate surface type.•Two-phase surface allows depositing conductive copper lines utilizing laser.•Dispersity of defects on interfaces may be described in terms of statistical modeling.
In this work we study the influence of
l
-(+)-КNaC
4
H
4
O
6
× 4H
2
O (KNaT) and
l
-H
2
C
4
H
4
O
6
(H
2
T) on the complexation processes occurring during in situ laser-induced catalytic destruction ...of the organic components of the aqueous solutions with formation of the unsaturated hydrocarbons. For that purpose, ATR-FTIR, Raman, IR, and NIR spectroscopy as well as quantum chemical calculations were implemented. It was observed that hydration of T
2−
anion via carboxylate groups is stronger than that via hydroxyl groups. We also established the changes in the spectral characteristics of the absorption bands corresponding to vibrations of T
2−
, HT
−
, and H
2
T, at solid state-liquid and acid-salt transitions, depending on concentration of the solution components and the OH
−
/H
2
T ratio. Finally, it was shown that ethylene is a main product of the catalytic destruction of the copper tartrate complexes.
In this work we demonstrate the role of a ligand in formation of the conductive and electrocatalytically active copper microstructures produced using the in situ laser-induced metal deposition ...technique. For this purpose, the alkaline solutions of different concentrations containing copper(II) chloride and Rochelle salt, which is used as the ligand and exhibits both coordination and reduction properties, were studied by ATR-FTIR, UV–Vis, and Raman spectroscopy. According to spectroscopic studies and theoretical considerations, it was observed that at certain concentrations and proportion of copper(II) chloride and sodium potassium tartrate, and also within pH range between 7 and 13 the components of the plating copper solution form the tartrate copper complex, in which copper ion is coordinated by four hydroxyl groups of the ligand and two hydroxyl groups of the environment. As a result, the laser-induced deposition from solutions, where copper coordination occurs via hydroxyls rather than through other functional groups (e.g. carboxylate), results in the synthesis of the sensory active materials. Furthermore, we figured out that the presence of the reducing agents such as polyols in the plating copper solution also enhances the electrical conductivity and electrochemical characteristics of the resulting copper microdeposits, among which sorbitol displays the most attractive results. Thus, it was shown that the regime of copper coordination in an organic ligand and number of hydroxyl groups in a ligand and a reducing agent directly affect the properties of the synthesized copper microstructures. In addition, the overall results obtained in this study are quite useful for better understanding the mechanisms of the laser-induced metal deposition process, and very perspective for development and design of new non-enzymatic electrochemical sensors and biosensors. Keywords: Rochelle salt, ATR-FTIR, Laser-induced copper deposition, Tartrate copper complex, Quantum-chemical calculations
Deep eutectic solvents (DES) have become a promising alternative to molecular organic solvents and ionic liquids in a variety of scientific applications. Their customizable physicochemical properties ...make them attractive for extraction, catalysis, electrochemistry and drug delivery. Recently, the study of not so much DES themselves, as their mixtures with water, has attracted particular interest. In this study, six widely used DESs based on choline chloride and carboxylic acids (citric, tartaric, malic, glycolic, malonic and lactic) with a water content of 0–50 wt% were analyzed. Properties such as density, viscosity, conductivity and spectral properties of DES (IR spectroscopy and refractive index) were studied. The results show that in the entire range of water content under study, there are no abrupt changes in properties for all the studied parameters, which allows us to conclude that water is gradually incorporated into the DES structure without its destruction. However, within this class of eutectic solvents, subclasses can be distinguished, due to various changes in the studied properties. These results provide important information for optimizing the performance of DES in practical applications and highlight their potential as sustainable green solvents in modern science and technology.
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•Density, viscosity, conductivity of DESs based choline chloride and carboxyl acids and water were investigated.•The water is gradually incorporated into the DES structure without its decomposition.•DESs can be divided into two subclasses: Newtonian and non-Newtonian, based on their rheological properties.•Two subclasses of eutectic solvents can be identified based on the number of functional groups in the original acids.
In this study, we explore the feasibility of a promising approach to fabricate conductive copper patterns with arbitrary topology on various dielectric substrates using direct laser metallization ...from deep eutectic solvents. We demonstrate the capability to print on industrially relevant dielectric materials, including polyimide, fiberglass plastic, and polytetrafluoroethylene (PTFE) substrates. We investigate the geometric and electrical characteristics of the resulting patterns and their composition. Our findings highlight the significant influence of the substrate material on both the formation rate of structures and their final properties. The characteristic resistance of the fabricated copper patterns is in the range from 0.23 to 1.64 Ω × mm2/m. The rate of pattern formation varied from 0.5 to 3.5 mm/s, depending on the substrate used.
Heat is a well-known treatment method for a wide range of diseases. Hyperthermia treatment or intentional overheating of cells is a rapidly developing therapeutic strategy in cancer treatment. ...All-dielectric nanophotonics has established itself in optical applications, including nanothermometry and optical heating; generally, it involves Mie resonances in nonplasmonic nanoparticles (NPs). However, such nanomaterials do not always provide sufficient heating due to their nonoptimal size distribution after fabrication by nonlithographic approaches. To overcome this limitation, additional steps, such as size-separation of NPs, are required. Another strategy for efficient heating is intelligent integration of plasmonic and all-dielectric nanostructures to develop hybrid nanomaterials with outstanding optical performances, e.g., efficient nanoheaters and nanothermometers. Taking this into account, we report on a simple and accessible approach for the fabrication of hybrid silicon–gold NPs. Their heating abilities are further compared with those of pristine monodispersed Si NPs inside and outside B16–F10 melanoma cells and confirmed by simultaneous nanoscale thermometry. The obtained results show that the obtained hybrid nanomaterials are more efficient nanoheaters even in biological environments, where cell inhomogeneity and deviations of NP sizes make it difficult to exactly meet the critical coupling conditions.
Catalytic actions of aluminum chloride on laser-induced liquid-phase copper deposition process were studied. Copper deposition experiments in aqueous solutions containing aluminum chloride upon 532 ...nm laser irradiation at different line deposition rate were performed. The influence of pH on the deposition rate and topology of the deposited copper microstructures was investigated. Enhanced rate of copper reduction in aluminum chloride solutions was observed. High purity copper microstructures with good electrical conductivity were obtained.
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