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Development of robust and cost-effective smart materials requires rational chemical nanoengineering to provide viable technological solutions for a wide range of applications. Recently, a powerful approach based on the electrografting of diazonium salts has attracted a great deal of attention due to its numerous technological advantages. Several studies on graphene-based materials reveal that the covalent attachment of aryl groups via the above approach could lead to additional beneficial properties of this versatile material. Here, we developed the covalently linked metalorganic wires on two transparent, cheap, and conductive materials: fluorine-doped tin oxide (FTO) and FTO/single-layer graphene (FTO/SLG). The wires are terminated with nitrilotriacetic acid metal complexes, which are universal molecular anchors to immobilize His6-tagged proteins, such as biophotocatalysts and other types of redox-active proteins of great interest in biotechnology, optoelectronics, and artificial photosynthesis. We show for the first time that the covalent grafting of a diazonium salt precursor on two different electron-rich surfaces leads to the formation of the molecular wires that promote p-doping of SLG concomitantly with a significantly enhanced unidirectional cathodic photocurrent up to 1 ?A cm-2. Density functional theory modeling reveals that the exceptionally high photocurrent values are due to two distinct mechanisms of electron transfer originating from different orbitals/bands of the diazonium-derived wires depending on the nature of the chelating metal redox center. Importantly, the novel metalorganic interfaces reported here exhibit minimized back electron transfer, which is essential for the maximization of solar conversion efficiency. © 2022 American Chemical Society. All rights reserved.

A new indium precursor, namely, indium(II) chloride, was tested as a precursor in the synthesis of ternary Ag−In−S and quaternary Ag−In−Zn−S nanocrystals. This new precursor, being in fact a dimer of Cl2In−InCl2 chemical structure, is significantly more reactive than InCl3, typically used in the preparation of these types of nanocrystals. This was evidenced by carrying out comparative syntheses under the same reaction conditions using these two indium precursors in combination with the same silver (AgNO3) and zinc (zinc stearate) precursors. In particular, the use of indium(II) chloride in combination with low concentrations of the zinc precursor yielded spherical-shaped (D = 3.7−6.2 nm) Ag−In−Zn−S nanocrystals, whereas for higher concentrations of this precursor, rodlike nanoparticles (L = 9−10 nm) were obtained. In all cases, the resulting nanocrystals were enriched in indium (In/Ag = 1.5−10.3). Enhanced indium precursor conversion and formation of anisotropic, longitudinal nanoparticles were closely related to the presence of thiocarboxylic acid type of ligands in the reaction mixture. These ligands were generated in situ and subsequently bound to surfacial In(III) cations in the growing nanocrystals. The use of the new precursor of enhanced reactivity facilitated precise tuning of the photoluminescence color of the resulting nanocrystals in the spectral range from ca. 730 to 530 nm with photoluminescence quantum yield (PLQY) varying from 20 to 40%. The fabricated Ag−In−S and Ag−In−Zn−S nanocrystals exhibited the longest, reported to date, photoluminescence lifetimes of ∼9.4 and ∼1.4 μs, respectively. It was also demonstrated for the first time that ternary (Ag−In− S) and quaternary (Ag−In−Zn−S) nanocrystals could be applied as efficient photocatalysts, active under visible light (green) illumination, in the reaction of aldehydes reduction to alcohols.

SnS-Ti/TiO2photoanode for anticancer drug degradation.

This paper presents application of Finite Element Method in designing of a vibroisolated object. A model of power generator of 113 MW was chosen for the analysis. Such the generator is used in one of power plants in Silesia district. Several frequency domain dynamic analyses aimed at assessment of influence of vibroisolation on acceleration level of the generator foundation were performed. Three different models of the generator were considered. For the purposes of verification of the obtained results measured vibration accelerations were used.

Inspired by the easy intercalation of quinoxaline heterocyclic aromatic amines (HAAs) in double-stranded DNA (dsDNA), we synthesized a nucleobase-functionalized molecularly imprinted polymer (MIP) as the recognition unit of an impedimetric chemosensor for the selective determination of a 2-amino-3,7,8-trimethyl-3H-imidazo[4,5-f]quinoxaline (7,8-DiMeIQx) HAA. HAAs are generated in meat and fish processed at high temperatures. They are considered to be potent hazardous carcinogens. The MIP film was prepared by potentiodynamic electropolymerization of a pre-polymerization complex of two adenine- and one thymine-substituted bis(2,2′-bithien-5-yl)methane functional monomer molecules with one 7,8-DiMeIQx template molecule, in the presence of the 2,4,5,2′,4′,5′-hexa(thiophene-2-yl)-3,3′-bithiophene cross-linking monomer, in solution. The as-formed MIP chemosensor allowed for the selective impedimetric determination of 7,8-DiMeIQx in the 47 to 400 μM linear dynamic concentration range with a limit of detection of 15.5 μM. The chemosensor was successfully applied for 7,8-DiMeIQx determination in the pork meat extract as a proof of concept.

Herein, we report the potential-driven electrochemical transformation carried out in basic media of two Ni

The structural and chemical modification of TiO

In this work, the effect of various ionic liquids (ILs), namely, choline chloride [Chol][Cl], hexadecylpyridynium chloride [HDPy][Cl], and tributylmethylammonium chloride [TBMA][Cl], on the morphology, surface composition in relation to photocatalytic oxidation of 5-fluorouracil (5-FU) and phenol in the presence of TiO2 photocatalysts under artificial sunlight conditions was investigated. The highest photoactivity towards cytostatic drug removal was found when [TBMA][Cl] was used for the synthesis, for phenol removal photoactivity was not changed in all cases. Among the selected ionic liquids, only [TMBA][Cl] made it possible to form the Ti3+ species, which was equivalent to the occurrence of oxygen vacancies and was beneficial for the photocatalytic activity. Moreover, the increase of ILs-TiO2 photoactivity was assigned to the presence of IL or IL’s organic residues on the photocatalyst surface responsible for better hole and electron separation. The mechanism of 5-FU degradation over the most photoactive photocatalyst was varied under different types of light irradiation, and •OHfree radicals were the major entities in the drug removal under UV light, while holes and •OHfree radicals under solar light. These studies represent a promising approach to cytostatic drug removal in the presence of TiO2 microspheres prepared in the presence of others than imidazolium-based ILs.

One of the challenges in research into photoelectrocatalytic (PEC) degradation of pollutants is finding the appropriate photoanode material, which has a significant impact on the process efficiency. Among all others, photoelectrodes based on an ordered TiO2 nanotube arrays are a promising material due to well-developed surface area and efficient charge separation. To increase the PEC activity of this material, the SILAR method was used to decorate Ti/TiO2 nanotubes by PbS quantum dots (QD). The ifosfamide (IF) degradation rate constants was twice as higher for PbS-Ti/TiO2 (0.0148 min 1) than for Ti/TiO2 (0.0072 min 1). Our research showed the highest efficiency of PEC degradation of drugs using IIIPbS-Ti/TiO2 made with 3 SILAR cycles (PbS QD size mainly 2–4 nm). The 4 and 6 of SILAR cycles resulted in the aggregation of PbS nanoparticles on the Ti/ TiO2 surface and decreased IF PEC degradation rate to 0.0043 and 0.0033 min 1, respectively. Research on PEC mechanism has shown that the drugs are degraded mainly by the activity of photogenerated holes and hydroxyl radicals. In addition, the identified drug intermediates made possible to propose a degradation pathways of anticancer drugs and the ecotoxicity test show no inhibition of Lemna minor growth of treated solutions.

A novel two-step ionic liquid assisted procedure was applied for a controllable synthesis of BiOBr/Bi2WO6 heterojunction thin films. The preparation route involved an anodic oxidation of tungsten foil and hydrothermal transformation of as-anodized oxide in the presence of bismuth precursor and ionic liquid, N-butylpyridinium bromide [BPy][Br]. The BiOBr plates with irregular shapes adhered to the surface of flower-like Bi2WO6 and formed a heterojunction between BiOBr and Bi2WO6, as confirmed by the analysis of their structure and composition. The highest efficiency of phenol degradation was achieved when the highest amount of IL was used (the apparent quantum efficiency was almost 8 and 71.5 times higher compared to BiOBr and Bi2WO6, respectively). In addition, superoxide radicals (•O2–) were found as the main factor responsible for the photodegradation. A possible reaction mechanism was further investigated as a function of monochromatic irradiation to determine the exact range of the composite photoactivity.

Simultaneously, the p-synephrine 1 template was imprinted, and a ferrocene redox probe was covalently immobilized in a (bis-bithiophene)-based polymer, and the resulting molecularly imprinted polymer (MIP) was deposited on the Pt electrode as a thin film to form a redox self-reporting MIP film-based chemosensor. After subsequent template extraction from the film, analyte 1 was determined with differential pulse voltammetry (DPV) in a (redox probe)-free solution. That was possible because the internal ferrocene redox probe generated the DPV analytical signal. The thickness and morphology of the film were crucial for the sensor's performance. The self-reporting mechanism was examined with electrochemical techniques, simultaneous piezomicrogravimetry and electrochemistry at an electrochemical quartz crystal microbalance, and surface plasmon resonance spectroscopy. The chemosensor was applied for selective p-synephrine determination in a concentration range of 2.0–75 nM with the LOD of 0.57 nM at S/N = 3.