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In this work, we proposed a rapid single-stage laser-induced fabrication of bimetallic micro-patterns on an oxide glass surface using deep eutectic solvents (DESs) consisting of choline chloride, citric acid along with nickel, copper and cobalt acetates as metallization solutions. The resulting bimetallic micropatterns were tested as working electrodes for non-enzymatic determination of dopamine. The linear range for dopamine detection was found to be 1–500 µM, with a sensitivity of 340.4 µA mM−1 and 615.2 µA mM−1 and a detection limit of 0.36 µM and 0.51 µM for Ni-Cu and Ni-Co sensor, respectively. For the first time, bimetallic Ni-Cu and Ni-Co structures have been obtained from DESs for high-performance dopamine detection with great potential for further application in non-enzymatic sensing and biosensing.

The precise control of nanostructure and surface atomic arrangement can be used to tune the electrocatalytic properties of materials and improve their performance. Unfortunately, the long-term structural stability of electrocatalysts with complex nanoscale morphology, a necessary requirement for industrial implementation, often remains elusive. Here we study how electrochemical and complex current behaviours affect the nanoscale object and its structural stability during electrocatalysis. We find that metal electromigration can drive structural transformation during electrolysis to minimize current crowding in nanoscale geometric constrictions. This electrical phenomenon, acting in combination with electrochemically induced atomic migration, can result in specific structural transformations of the catalyst, with the extent and rate depending on the material, geometry and reaction. Using a series of nanostructure examples, we establish a general framework for evaluating the structural transformations in cathodic metal nanocatalysts and explain specific qualitative trends. In conjunction with catalyst design rules, this mechanistic framework will facilitate the development of nanostructured electrocatalysts with sufficient stability for sustainable applications. The structural stability of electrocatalysts with complex nanoscale morphology, a requirement for their industrial implementation, often remains elusive. Now, a combination of electrical and electrochemical effects is shown to drive specific structural transformations of the catalyst during electrolysis.

We report one-step synthesis of carbon-based microstructures on the surface of polyimide by using the 2D direct laser writing technique. It was shown that the properties of obtained conductive structures can be tuned by varying the conditions of the laser synthesis (scanning speed, laser power). The fabricated materials exhibited high electrochemical activity towards d-glucose measured by cyclic voltammetry analysis (limit of detection—0.564 μM and 6.31 μM for different linear ranges). Comparatively high sensing activity of the synthesized structures makes them promising materials for flexible non-enzymatic biosensing devices.

In this work we study the influence of l-(+)-КNaC4H4O6 × 4H2O (KNaT) and l-H2C4H4O6 (H2T) 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 T2− 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 T2−, HT−, and H2T, at solid state-liquid and acid-salt transitions, depending on concentration of the solution components and the [OH−]/[H2T] ratio. Finally, it was shown that ethylene is a main product of the catalytic destruction of the copper tartrate complexes.

The simple and cheap method for fabrication of micro-sized electrochemical electrodes was proposed. The porous copper microstructures synthesized by laser-induced metal deposition technique were used as an indicator electrode, whereas a bulk polycrystalline copper with similar geometric parameters was used as an etalon electrode. The electrochemical properties of these electrodes were studied by cyclic voltammetry and impedance spectroscopy. The surface of the deposited copper structures was investigated by X-ray photoelectron spectroscopy and atomic force microscopy. An analytical response of the fabricated copper electrode is 15 times higher than those observed for a pure bulk copper. A study of sensory characteristics for hydrogen peroxide and d-glucose detection showed that the value of Faraday current at the fabricated copper electrode is 2–2.5 orders of magnitude higher than for etalon one.