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Poly(vinyl chloride)/Nanocarbon Composites for Advanced Potentiometric Membrane Sensor Design. Int J Mol Sci 2024; 25:1124. [PMID: 38256194 PMCID: PMC10816362 DOI: 10.3390/ijms25021124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 01/11/2024] [Accepted: 01/15/2024] [Indexed: 01/24/2024] Open
Abstract
Polymer nanocomposites filled with carbon nanoparticles (CNPs) are a hot topic in materials science. This article discusses the current research on the use of these materials as interfacial electron transfer films for solid contact potentiometric membrane sensors (SC-PMSs). The results of a comparative study of plasticized poly (vinyl chloride) (pPVC) matrices modified with single-walled carbon nanotubes (SWCNTs), fullerenes-C60, and their hybrid ensemble (SWCNTs-C60) are reported. The morphological characteristics and electrical conductivity of the prepared nanostructured composite films are reported. It was found that the specific electrical conductivity of the pPVC/SWCNTs-C60 polymer film was higher than that of pPVC filled with individual nanocomponents. The effectiveness of this composite material as an electron transfer film in a new potentiometric membrane sensor for detecting phenylpyruvic acid (in anionic form) was demonstrated. Screening for this metabolic product of phenylalanine in body fluids is of significant diagnostic interest in phenylketonuria (dementia), viral hepatitis, and alcoholism. The developed sensor showed a stable and fast Nernstian response for phenylpyruvate ions in aqueous solutions over the wide linear concentration range of 5 × 10-7-1 × 10-3 M, with a detection limit of 10-7.2 M.
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Synthesis and Structures of Lead(II) Complexes with Substituted Derivatives of the Closo-Decaborate Anion with a Pendant N 3 Group. Molecules 2023; 28:8073. [PMID: 38138563 PMCID: PMC10746007 DOI: 10.3390/molecules28248073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 12/05/2023] [Accepted: 12/11/2023] [Indexed: 12/24/2023] Open
Abstract
In this work, we studied lead(II) and cobalt(II) complexation of derivatives [2-B10H9O(CH2)2O(CH2)2N3]2- and [2-B10H9O(CH2)5N3]2- of the closo-decaborate anion containing pendant azido groups in the presence of 1,10-phenanthroline and 2,2'-bipyridyl. Mononuclear [PbL2{An}] and binuclear [Pb2L4(NO3)2{An}] lead complexes (where {An} is the N3-substituted boron cluster) were isolated and studied by IR spectroscopy and elemental analysis. The mononuclear lead(II) complex [Pb(phen)2[B10H9O(CH2)2O(CH2)2N3] and the binuclear lead(II) complex [Pb2(phen)4(NO3)2[B10H9O(CH2)5)N3] were determined by single-crystal X-ray diffraction. In complex [Pb2(phen)4(NO3)2[B10H9O(CH2)5)N3], the boron cluster is coordinated by the metal atom only via the 3c2e MHB bonds. In complex [Pb(phen)2[B10H9O(CH2)2O(CH2)2N3], the coordination environment of the metal includes BH groups of the boron cluster and the oxygen atom of the exo-polyhedral substituent. When the reaction was performed in a CH3CN/water mixture, the binuclear lead(II) complex [(Pb(bipy)NO3)(Pb(bipy)2NO3)(B10H9O(CH2)2O(CH2)2N3)]·CH3CN·H2O was isolated, where the boron cluster acts as a bridging ligand between lead atoms coordinated by the boron cage via the O atoms of the substituent and/or the BH groups. In the course of cobalt(II) complexation, the starting compound (Ph4P)2[B10H9O(CH2)5N3] was isolated and its structure was also determined by X-ray diffraction. Although a number of lead(II) complexes with coordinated N3 are known from the literature, no complexes with the boron cluster coordinated by the pendant N3 group involved in the metal coordination have been isolated.
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Current Trends and Promising Electrode Materials in Micro-Supercapacitor Printing. MATERIALS (BASEL, SWITZERLAND) 2023; 16:6133. [PMID: 37763411 PMCID: PMC10533130 DOI: 10.3390/ma16186133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 09/05/2023] [Accepted: 09/07/2023] [Indexed: 09/29/2023]
Abstract
The development of scientific and technological foundations for the creation of high-performance energy storage devices is becoming increasingly important due to the rapid development of microelectronics, including flexible and wearable microelectronics. Supercapacitors are indispensable devices for the power supply of systems requiring high power, high charging-discharging rates, cyclic stability, and long service life and a wide range of operating temperatures (from -40 to 70 °C). The use of printing technologies gives an opportunity to move the production of such devices to a new level due to the possibility of the automated formation of micro-supercapacitors (including flexible, stretchable, wearable) with the required type of geometric implementation, to reduce time and labour costs for their creation, and to expand the prospects of their commercialization and widespread use. Within the framework of this review, we have focused on the consideration of the key commonly used supercapacitor electrode materials and highlighted examples of their successful printing in the process of assembling miniature energy storage devices.
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Composites and Materials Prepared from Boron Cluster Anions and Carboranes. MATERIALS (BASEL, SWITZERLAND) 2023; 16:6099. [PMID: 37763377 PMCID: PMC10533147 DOI: 10.3390/ma16186099] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 09/04/2023] [Accepted: 09/04/2023] [Indexed: 09/29/2023]
Abstract
Here, we present composites and materials that can be prepared starting with boron hydride cluster compounds (decaborane, decahydro-closo-decaborate and dodecahydro-closo-dodecaborate anions and carboranes). Recent examples of their utilization as boron protective coatings including using them to synthesize boron carbide, boron nitride, metal borides, metal-containing composites, and neutron shielding materials are discussed. The data are generalized demonstrate the versatile application of materials based on boron cluster anions and carboranes in various fields.
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Oxidation of Ceramic Materials Based on HfB 2-SiC under the Influence of Supersonic CO 2 Jets and Additional Laser Heating. Int J Mol Sci 2023; 24:13634. [PMID: 37686438 PMCID: PMC10488200 DOI: 10.3390/ijms241713634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 08/18/2023] [Accepted: 09/02/2023] [Indexed: 09/10/2023] Open
Abstract
The features of oxidation of ultra-high-temperature ceramic material HfB2-30 vol.%SiC modified with 1 vol.% graphene as a result of supersonic flow of dissociated CO2 (generated with the use of high-frequency induction plasmatron), as well as under the influence of combined heating by high-speed CO2 jets and ytterbium laser radiation, were studied for the first time. It was found that the addition of laser radiation leads to local heating of the central region from ~1750 to ~2000-2200 °C; the observed temperature difference between the central region and the periphery of ~300-550 °C did not lead to cracking and destruction of the sample. Oxidized surfaces and cross sections of HfB2-SiC-CG ceramics with and without laser heating were investigated using X-ray phase analysis, Raman spectroscopy and scanning electron microscopy with local elemental analysis. During oxidation by supersonic flow of dissociated CO2, a multilayer near-surface region similar to that formed under the influence of high-speed dissociated air flows was formed. An increase in surface temperature with the addition of laser heating from 1750-1790 to 2000-2200 °C (short term, within 2 min) led to a two to threefold increase in the thickness of the degraded near-surface area of ceramics from 165 to 380 microns. The experimental results indicate promising applications of ceramic materials based on HfB2-SiC as part of high-speed flying vehicles in planetary atmospheres predominantly composed of CO2 (e.g., Venus and Mars).
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Hydrothermal Synthesis of a Cellular NiO Film on Carbon Paper as a Promising Way to Obtain a Hierarchically Organized Electrode for a Flexible Supercapacitor. MATERIALS (BASEL, SWITZERLAND) 2023; 16:5208. [PMID: 37569912 PMCID: PMC10420231 DOI: 10.3390/ma16155208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 07/20/2023] [Accepted: 07/23/2023] [Indexed: 08/13/2023]
Abstract
The formation of a cellular hierarchically organized NiO film on a carbon paper substrate under hydrothermal conditions using triethanolamine as a base has been studied. The thermal behavior of the carbon paper substrate with the applied semi-product shell was studied using synchronous thermal analysis (TGA/DSC) and it was demonstrated that such modification of the material surface leads to a noticeable increase in its thermal stability. Using scanning electron microscopy (SEM), it was shown that the NiO film grown on the carbon fiber surface is characterized by a complex cellular morphology, organized by partially layered individual nanosheets of about 4-5 nm thickness and lateral dimensions up to 1-2 μm, some edges and folds of which are located vertically relative to the carbon fiber surface. The surface of the obtained material was also examined using atomic force microscopy (AFM), and the electronic work function of the oxide shell surface was evaluated using the Kelvin probe force microscopy (KPFM) method. The electrochemical parameters of the obtained flexible NiO/CP electrode were analyzed: the dependence of the specific capacitance on the current density was determined and the stability of the material during cycling was studied, which showed that the proposed approach is promising for manufacturing hierarchically organized electrodes for flexible supercapacitors.
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Low Temperature Chemoresistive Oxygen Sensors Based on Titanium-Containing Ti 2CT x and Ti 3C 2T x MXenes. MATERIALS (BASEL, SWITZERLAND) 2023; 16:4506. [PMID: 37444820 DOI: 10.3390/ma16134506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 06/16/2023] [Accepted: 06/19/2023] [Indexed: 07/15/2023]
Abstract
The chemoresistive properties of multilayer titanium-containing Ti2CTx and Ti3C2Tx MXenes, synthesized by etching the corresponding MAX phases with NaF solution in hydrochloric acid, and the composites based on them, obtained by partial oxidation directly in a sensor cell in an air flow at 150 °C, were studied. Significant differences were observed for the initial MXenes, both in microstructure and in the composition of surface functional groups, as well as in gas sensitivity. For single Ti2CTx and Ti3C2Tx MXenes, significant responses to oxygen and ammonia were observed. For their partial oxidation at a moderate temperature of 150 °C, a high humidity sensitivity (T, RH = 55%) is observed for Ti2CTx and a high and selective response to oxygen for Ti3C2Tx at 125 °C (RH = 0%). Overall, these titanium-containing MXenes and composites based on them are considered promising as receptor materials for low temperature oxygen sensors.
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Microplotter Printing of a Miniature Flexible Supercapacitor Electrode Based on Hierarchically Organized NiCo 2O 4 Nanostructures. MATERIALS (BASEL, SWITZERLAND) 2023; 16:4202. [PMID: 37374386 DOI: 10.3390/ma16124202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 06/01/2023] [Accepted: 06/04/2023] [Indexed: 06/29/2023]
Abstract
The hydrothermal synthesis of a nanosized NiCo2O4 oxide with several levels of hierarchical self-organization was studied. Using X-ray diffraction analysis (XRD) and Fourier-transform infrared (FTIR) spectroscopy, it was determined that under the selected synthesis conditions, a nickel-cobalt carbonate hydroxide hydrate of the composition M(CO3)0.5(OH)·0.11H2O (where M-Ni2+ and Co2+) is formed as a semi-product. The conditions of semi-product transformation into the target oxide were determined by simultaneous thermal analysis. It was found by means of scanning electron microscopy (SEM) that the main powder fraction consists of hierarchically organized microspheres of 3-10 μm in diameter, and individual nanorods are observed as the second fraction of the powder. Nanorod microstructure was further studied by transmission electron microscopy (TEM). A hierarchically organized NiCo2O4 film was printed on the surface of a flexible carbon paper (CP) using an optimized microplotter printing technique and functional inks based on the obtained oxide powder. It was shown by XRD, TEM, and atomic force microscopy (AFM) that the crystalline structure and microstructural features of the oxide particles are preserved when deposited on the surface of the flexible substrate. It was found that the obtained electrode sample is characterized by a specific capacitance value of 420 F/g at a current density of 1 A/g, and the capacitance loss during 2000 charge-discharge cycles at 10 A/g is 10%, which indicates a high material stability. It was established that the proposed synthesis and printing technology enables the efficient automated formation of corresponding miniature electrode nanostructures as promising components for flexible planar supercapacitors.
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Obtaining of ZnO/Fe 2O 3 Thin Nanostructured Films by AACVD for Detection of ppb-Concentrations of NO 2 as a Biomarker of Lung Infections. BIOSENSORS 2023; 13:bios13040445. [PMID: 37185520 PMCID: PMC10136079 DOI: 10.3390/bios13040445] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 03/26/2023] [Accepted: 03/29/2023] [Indexed: 05/17/2023]
Abstract
ZnO/Fe2O3 nanocomposites with different concentration and thickness of the Fe2O3 layer were obtained by two-stage aerosol vapor deposition (AACVD). It was shown that the ZnO particles have a wurtzite structure with an average size of 51-66 nm, and the iron oxide particles on the ZnO surface have a hematite structure and an average size of 23-28 nm. According to EDX data, the iron content in the films was found to be 1.3-5.8 at.%. The optical properties of the obtained films were studied, and the optical band gap was found to be 3.16-3.26 eV. Gas-sensitive properties at 150-300 °C were studied using a wide group of analyte gases: CO, NH3, H2, CH4, C6H6, ethanol, acetone, and NO2. A high response to 100 ppm acetone and ethanol at 225-300 °C and a high and selective response to 300-2000 ppb NO2 at 175 °C were established. The effect of humidity on the magnitude and shape of the signal obtained upon NO2 detection was studied.
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Synthesis and Structures of Lead(II) Complexes with Hydroxy-Substituted Closo-Decaborate Anions. INORGANICS 2023. [DOI: 10.3390/inorganics11040144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/31/2023] Open
Abstract
Mixed-ligand lead(II) complexes with 2,2′-bipyridyl and [B10H9OH]2− or monosubstituted hydroxy-substituted closo-decaborate anions with a pendant hydroxy group, separated from the boron cage by an alkoxylic spacer of different lengths [B10H9O(CH2)xO(CH2)2OH]]2− (x = 2 or 5) have been synthesized. Compounds have been characterized by IR and multinuclear NMR spectroscopies. The structures of binuclear complex [Pb(bipy)2[B10H9OH]]2·CH3CN (1·CH3CN), mononuclear complex [Pb(bipy)2[B10H9O(CH2)2O(CH2)2OH]]·0.5bipy·CH3CN (2·0.5bipy·CH3CN), and polymeric complex [Pb(bipy)[B10H9O(CH2)5O(CH2)2OH]]n (3) have been determined by single-crystal X-ray diffraction. In all three compounds, the co-ordination polyhedra of lead(II) are formed by N atoms from two bipy molecules, O atoms of the substituent attached to the boron cage, and BH groups of the boron cage.
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Gas-Sensitive Properties of ZnO/Ti 2CT x Nanocomposites. MICROMACHINES 2023; 14:725. [PMID: 37420958 DOI: 10.3390/mi14040725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 03/17/2023] [Accepted: 03/22/2023] [Indexed: 07/09/2023]
Abstract
At present, a new class of 2D nanomaterials, MXenes, is of great scientific and applied interest, and their application prospects are very broad, including as effective doping components for receptor materials of MOS sensors. In this work we have studied the influence on the gas-sensitive properties of nanocrystalline zinc oxide synthesized by atmospheric pressure solvothermal synthesis, with the addition of 1-5% of multilayer two-dimensional titanium carbide Ti2CTx, obtained by etching Ti2AlC with NaF solution in hydrochloric acid. It was found that all the obtained materials have high sensitivity and selectivity with respect to 4-20 ppm NO2 at a detection temperature of 200 °C. It is shown that the selectivity towards this compound is best for the sample containing the highest amount of Ti2CTx dopant. It has been found that as the MXene content increases, there is an increase in nitrogen dioxide (4 ppm) from 1.6 (ZnO) to 20.5 (ZnO-5 mol% Ti2CTx). reactions which the responses to nitrogen dioxide increase. This may be due to the increase in the specific surface area of the receptor layers, the presence of MXene surface functional groups, as well as the formation of the Schottky barrier at the interface between the phases of the components.
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Application of Titanium Carbide MXenes in Chemiresistive Gas Sensors. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:nano13050850. [PMID: 36903729 PMCID: PMC10004978 DOI: 10.3390/nano13050850] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 02/17/2023] [Accepted: 02/20/2023] [Indexed: 05/14/2023]
Abstract
The titanium carbide MXenes currently attract an extreme amount of interest from the material science community due to their promising functional properties arising from the two-dimensionality of these layered structures. In particular, the interaction between MXene and gaseous molecules, even at the physisorption level, yields a substantial shift in electrical parameters, which makes it possible to design gas sensors working at RT as a prerequisite to low-powered detection units. Herein, we consider to review such sensors, primarily based on Ti3C2Tx and Ti2CTx crystals as the most studied ones to date, delivering a chemiresistive type of signal. We analyze the ways reported in the literature to modify these 2D nanomaterials for (i) detecting various analyte gases, (ii) improving stability and sensitivity, (iii) reducing response/recovery times, and (iv) advancing a sensitivity to atmospheric humidity. The most powerful approach based on designing hetero-layers of MXenes with other crystals is discussed with regard to employing semiconductor metal oxides and chalcogenides, noble metal nanoparticles, carbon materials (graphene and nanotubes), and polymeric components. The current concepts on the detection mechanisms of MXenes and their hetero-composites are considered, and the background reasons for improving gas-sensing functionality in the hetero-composite when compared with pristine MXenes are classified. We formulate state-of-the-art advances and challenges in the field while proposing some possible solutions, in particular via employing a multisensor array paradigm.
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Synthesis of Disubstituted Carboxonium Derivatives of Closo-Decaborate Anion [2,6-B 10H 8O 2CC 6H 5] -: Theoretical and Experimental Study. Molecules 2023; 28:molecules28041757. [PMID: 36838745 PMCID: PMC9966448 DOI: 10.3390/molecules28041757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 02/09/2023] [Accepted: 02/09/2023] [Indexed: 02/16/2023] Open
Abstract
A comprehensive study focused on the preparation of disubstituted carboxonium derivatives of closo-decaborate anion [2,6-B10H8O2CC6H5]- was carried out. The proposed synthesis of the target product was based on the interaction between the anion [B10H11]- and benzoic acid C6H5COOH. It was shown that the formation of this product proceeds stepwise through the formation of a mono-substituted product [B10H9OC(OH)C6H5]-. In addition, an alternative one-step approach for obtaining the target derivative is postulated. The structure of tetrabutylammonium salts of carboxonium derivative ((C4H9)4N)[2,6-B10H8O2CC6H5] was established with the help of X-ray structure analysis. The reaction pathway for the formation of [2,6-B10H8O2CC6H5]- was investigated with the help of density functional theory (DFT) calculations. This process has an electrophile induced nucleophilic substitution (EINS) mechanism, and intermediate anionic species play a key role. Such intermediates have a structure in which one boron atom coordinates two hydrogen atoms. The regioselectivity for the process of formation for the 2,6-isomer was also proved by theoretical calculations. Generally, in the experimental part, the simple and available approach for producing disubstituted carboxonium derivative was introduced, and the mechanism of this process was investigated with the help of theoretical calculations. The proposed approach can be applicable for the preparation of a wide range of disubstituted derivatives of closo-borate anions.
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Microextrusion Printing of Multilayer Hierarchically Organized Planar Nanostructures Based on NiO, (CeO 2) 0.8(Sm 2O 3) 0.2 and La 0.6Sr 0.4Co 0.2Fe 0.8O 3-δ. MICROMACHINES 2022; 14:3. [PMID: 36677064 PMCID: PMC9865654 DOI: 10.3390/mi14010003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/20/2022] [Revised: 12/11/2022] [Accepted: 12/18/2022] [Indexed: 06/17/2023]
Abstract
In this paper, NiO, La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) and (CeO2)0.8(Sm2O3)0.2 (SDC) nanopowders with different microstructures were obtained using hydrothermal and glycol-citrate methods. The microstructural features of the powders were examined using scanning electron microscopy (SEM). The obtained oxide powders were used to form functional inks for the sequential microextrusion printing of NiO-SDC, SDC and LSCF-SDC coatings with resulting three-layer structures of (NiO-SDC)/SDC/(LSCF-SDC) composition. The crystal structures of these layers were studied using an X-ray diffraction analysis, and the microstructures were studied using atomic force microscopy. Scanning capacitance microscopy was employed to build maps of capacitance gradient distribution over the surface of the oxide layers, and Kelvin probe force microscopy was utilized to map surface potential distribution and to estimate the work function values of the studied oxide layers. Using SEM and an energy-dispersive X-ray microanalysis, the cross-sectional area of the formed three-layer structure was analyzed-the interfacial boundary and the chemical element distribution over the surface of the cross-section were investigated. Using impedance spectroscopy, the temperature dependence of the electrical conductivity was also determined for the printed three-layer nanostructure.
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Atmospheric Pressure Solvothermal Synthesis of Nanoscale SnO 2 and Its Application in Microextrusion Printing of a Thick-Film Chemosensor Material for Effective Ethanol Detection. SENSORS (BASEL, SWITZERLAND) 2022; 22:9800. [PMID: 36560169 PMCID: PMC9784031 DOI: 10.3390/s22249800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 12/09/2022] [Accepted: 12/12/2022] [Indexed: 06/17/2023]
Abstract
The atmospheric pressure solvothermal (APS) synthesis of nanocrystalline SnO2 (average size of coherent scattering regions (CSR)-7.5 ± 0.6 nm) using tin acetylacetonate as a precursor was studied. The resulting nanopowder was used as a functional ink component in microextrusion printing of a tin dioxide thick film on the surface of a Pt/Al2O3/Pt chip. Synchronous thermal analysis shows that the resulting semiproduct is transformed completely into tin dioxide nanopowder at 400 °C within 1 h. The SnO2 powder and the resulting film were shown to have a cassiterite-type structure according to X-ray diffraction analysis, and IR spectroscopy was used to establish the set of functional groups in the material composition. The microstructural features of the tin dioxide powder were analyzed using scanning (SEM) and transmission (TEM) electron microscopy: the average size of the oxide powder particles was 8.2 ± 0.7 nm. Various atomic force microscopy (AFM) techniques were employed to investigate the topography of the oxide film and to build maps of surface capacitance and potential distribution. The temperature dependence of the electrical conductivity of the printed SnO2 film was studied using impedance spectroscopy. The chemosensory properties of the formed material when detecting H2, CO, NH3, C6H6, C3H6O and C2H5OH, including at varying humidity, were also examined. It was demonstrated that the obtained SnO2 film has an increased sensitivity (the sensory response value was 1.4-63.5) and selectivity for detection of 4-100 ppm C2H5OH at an operating temperature of 200 °C.
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Synthesis of ((CeO 2) 0.8(Sm 2O 3) 0.2)@NiO Core-Shell Type Nanostructures and Microextrusion Printing of a Composite Anode Based on Them. MATERIALS (BASEL, SWITZERLAND) 2022; 15:8918. [PMID: 36556722 PMCID: PMC9781763 DOI: 10.3390/ma15248918] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/12/2022] [Revised: 12/02/2022] [Accepted: 12/12/2022] [Indexed: 06/17/2023]
Abstract
The process of the hydrothermal synthesis of hierarchically organized nanomaterials with the core-shell structure with the composition ((CeO2)0.8(Sm2O3)0.2)@NiO was studied, and the prospects for their application in the formation of planar composite structures using microextrusion printing were shown. The hydrothermal synthesis conditions of the (CeO2)0.8(Sm2O3)0.2 nanospheres were determined, and the approach to their surface modification by growing the NiO shell with the formation of core-shell structures equally distributed between the larger nickel(II) oxide nanosheets was developed. The resulting nanopowder was used as a functional ink component in the microextrusion printing of the corresponding composite coating. The microstructure of the powders and the oxide coating was studied by scanning (SEM) and transmission electron microscopy (TEM), the crystal structure was explored by X-ray diffraction analysis (XRD), the set of functional groups in the powders was studied by Fourier-transform infrared spectroscopy (FTIR) spectroscopy, and their thermal behavior in an air flow by synchronous thermal analysis (TGA/DSC). The electronic state of the chemical elements in the resulting coating was studied using X-ray photoelectron spectroscopy (XPS). The surface topography and local electrophysical properties of the composite coating were studied using atomic force microscopy (AFM) and Kelvin probe force microscopy (KPFM). Using impedance spectroscopy, the temperature dependence of the specific electrical conductivity of the obtained composite coating was estimated.
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Investigation of the Effect of Supersonic Flow of Dissociated Nitrogen on ZrB 2-HfB 2-SiC Ceramics Doped with 10 vol.% Carbon Nanotubes. MATERIALS (BASEL, SWITZERLAND) 2022; 15:8507. [PMID: 36500002 PMCID: PMC9738432 DOI: 10.3390/ma15238507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 11/25/2022] [Accepted: 11/27/2022] [Indexed: 06/17/2023]
Abstract
The method of fabricating dense ultra-high temperature ceramic materials ZrB2−HfB2−SiC−CCNT was developed using a combination of sol-gel synthesis and reaction hot pressing approaches at 1800 °C. It was found that the introduction of multilayer nanotubes (10 vol.%) led to an increase in the consolidation efficiency of ceramics (at temperatures > 1600 °C). The obtained ZrB2−HfB2−SiC and ZrB2−HfB2−SiC−CCNT materials were characterized by a complex of physical and chemical analysis methods. A study of the effects on the modified sample ZrB2−HfB2−SiC−CCNT composition speed flow of partially dissociated nitrogen, using a high-frequency plasmatron, showed that, despite the relatively low temperature established on the surface (≤1585 °C), there was a significant change in the chemical composition and surface microstructure: in the near-surface layer, zirconium−hafnium carbonitride, amorphous boron nitride, and carbon were present. The latter caused changes in crucial characteristics such as the emission coefficient and surface catalyticity.
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Microextrusion Printing of Hierarchically Structured Thick V 2O 5 Film with Independent from Humidity Sensing Response to Benzene. MATERIALS (BASEL, SWITZERLAND) 2022; 15:7837. [PMID: 36363430 PMCID: PMC9655664 DOI: 10.3390/ma15217837] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 10/28/2022] [Accepted: 11/03/2022] [Indexed: 06/16/2023]
Abstract
The process of V2O5 oxide by the combination of sol-gel technique and hydrothermal treatment using heteroligand [VO(C5H7O2)2-x(C4H9O)x] precursor was studied. Using thermal analysis, X-ray powder diffraction (XRD) and infra-red spectroscopy (IR), it was found that the resulting product was VO2(B), which after calcining at 300 °C (1 h), oxidized to orthorhombic V2O5. Scanning electron microscopy (SEM) results for V2O5 powder showed that it consisted of nanosheets (~50 nm long and ~10 nm thick) assembled in slightly spherical hierarchic structures (diameter ~200 nm). VO2 powder dispersion was used as functional ink for microextrusion printing of oxide film. After calcining the film at 300 °C (30 min), it was found that it oxidized to V2O5, with SEM and atomic force microscopy (AFM) results showing that the film structure retained the hierarchic structure of the powder. Using Kelvin probe force microscopy (KPFM), the work function value for V2O5 film in ambient conditions was calculated (4.81 eV), indicating a high amount of deficiencies in the sample. V2O5 film exhibited selective response upon sensing benzene, with response value invariable under changing humidity. Studies of the electrical conductivity of the film revealed increased resistance due to high film porosity, with conductivity activation energy being 0.26 eV.
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Non-Covalent Interactions in the Crystal Structures of Perbrominated Sulfonium Derivatives of the closo-Decaborate Anion. Int J Mol Sci 2022; 23:ijms231912022. [PMID: 36233323 PMCID: PMC9569861 DOI: 10.3390/ijms231912022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 09/21/2022] [Accepted: 09/22/2022] [Indexed: 10/29/2022] Open
Abstract
A new series of compounds based on perbrominated disubstituted sulfonium derivatives of the closo-decaborate anion (n-Bu4N)[2-B10Br9SR2] (R = n-Pr, i-Pr, n-Bu, n-C8H17, n-C12H25, n-C18H37) was obtained, characterised by modern physicochemical methods of analysis. According to the results of an X-ray diffraction study, some of the anions and solvate molecules were disordered. The cations (n-Bu4N)+ and anions [2-B10Br9SR2]- were associated via C-H…Br and H…H contacts. In addition, Br…Br interactions between anions were revealed. The role of these contacts was analysed in terms of Hirshfeld surface analysis, QTAIM theory and the NCI method using quantum chemical calculations. An increase in the size of the alkyl R moiety led to significant strengthening of the total energy of H…H interactions. In the case of R = -n-C18H37, a parallel mutual orientation of alkyl moieties was established that was similar to the packing of salts of fatty acids. The nature of C-H…Br and Br…Br interionic interactions was found to be attractive, in contrast to the repulsive nature of intermolecular Br…Br interactions.
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Features of the formation of d10 metal complexes with benzimidazoles derivatives in the presence of the closo-decaborate anion. Polyhedron 2022. [DOI: 10.1016/j.poly.2022.116108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Boron Cluster Anion [B12H12]2– in Zinc(II) and Cadmium(II) Complexation at the Presence of N-Donor Heterocyclic Ligands. J CLUST SCI 2022. [DOI: 10.1007/s10876-022-02263-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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22
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Polymeric anionic silver(I) complexes {Cat[Ag[B10H10]]} (Cat = Pr4N+, Ph4P+, Ph4As+) with facial and edge-facial coordination of the boron cluster. Polyhedron 2022. [DOI: 10.1016/j.poly.2022.115932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Iron(II), cobalt(II), and nickel(II) complexes with 1,10-phenanthroline and 2,2’-bipyridyl and the macropolyhedral borane cluster [trans-B20H18]2- as counterion. Polyhedron 2022. [DOI: 10.1016/j.poly.2022.115740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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B-F bonding and reactivity analysis of mono- and perfluoro-substituted derivatives of closo-borate anions (6, 10, 12): A computational study. Polyhedron 2022. [DOI: 10.1016/j.poly.2021.115559] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Hydrothermal Synthesis of Ag Thin Films and Their SERS Application. NANOMATERIALS 2021; 12:nano12010136. [PMID: 35010086 PMCID: PMC8746704 DOI: 10.3390/nano12010136] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 12/26/2021] [Accepted: 12/28/2021] [Indexed: 11/16/2022]
Abstract
In this article, a facile, one-step method for the formation of silver thin-film nanostructures on the surface of Al2O3 substrates using the hydrothermal method is proposed. The dependence of the SERS effect intensity of the formed films during the detection of methylene blue (MB) low concentrations on the synthesis conditions, additional temperature treatment, and laser radiation wavelength (532 and 780 nm) in comparison with similar dye films on commercial SERS substrates is shown. The detection limit of the analyte used for the indicated lasers is estimated. The effect of the synthesis temperature on the particle size, crystal structure, and microstructure features of the obtained thin films based on silver nanoparticles is demonstrated. Using spreading resistance microscopy, the interface between the substrate and Ag particles is studied, and the dependence of the size of the corresponding gap between them and the nature of microstructural defects on the parameters of hydrothermal treatment of reaction systems in the presence of Al2O3 substrates is shown. As a result of the study, the factors associated with the properties of the obtained SERS substrates and the parameters of recording the spectra, which affect the amplification factor of the spectral lines intensity of the analyte, are revealed.
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Primary Amine Nucleophilic Addition to Nitrilium Closo-Dodecaborate [B 12H 11NCCH 3] -: A Simple and Effective Route to the New BNCT Drug Design. Int J Mol Sci 2021; 22:ijms222413391. [PMID: 34948186 PMCID: PMC8707455 DOI: 10.3390/ijms222413391] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 12/07/2021] [Accepted: 12/10/2021] [Indexed: 11/16/2022] Open
Abstract
In the present work, a convenient and straightforward approach to the preparation of borylated amidines based on the closo-dodecaborate anion [B12H11NCCH3NHR]-, R=H, Alk, Ar was developed. This method has two stages. A nitrile derivative of the general form [B12H11NCCH3]- was obtained, using a modified technique, in the first stage. On the second stage the resulting molecular system interacted with primary amines to form the target amidine products. This approach is characterised by a simple chemical apparatus, mild conditions and high yields of the final products. The mechanism of the addition of amine to the nitrile derivative of the closo-dodecaborate anion was studied, using quantum-chemical methods. The interaction between NH3 and [B12H11NCCH3]- ammonia was chosen as an example. It was found that the structure of the transition state determines the stereo-selectivity of the process. A study of the biological properties of borylated amidine sodium salts indicated that the substances had low toxicity and could accumulate in cancer cells in significant amounts.
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Theoretical and experimental comparison of the reactivity of the sulfanyl-closo-decaborate and sulfanyl-closo-dodecaborate anions and their mono-S-substituted derivatives. Polyhedron 2021. [DOI: 10.1016/j.poly.2021.115347] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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Synthesis of Perchlorinated Sulfonium Derivatives of closo-Decaborate Anion [2-B 10Cl 9SR 2] - (R = i-C 3H 7, n-C 3H 7, n-C 4H 9, n-C 8H 17, n-C 12H 25, n-C 18H 37, CH 2Ph, and cyclo-S(CH 2) 4). Inorg Chem 2021; 60:8592-8604. [PMID: 34042435 DOI: 10.1021/acs.inorgchem.1c00516] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A method for obtaining perchlorinated di-S,S-substituted derivatives of the closo-decaborate anion with various alkyl groups has been developed: [B10Cl9SR2]- (R= i-C3H7, n-C3H7, n-C4H9, n-C8H17, n-C12H25, n-C18H37, CH2Ph, and cyclo-S(CH2)4). The method is based on the preparation of the sulfonium-substituted anion [B10H9SR2]- by alkylation of the anion [B10H9SH]2- with bromoalkanes (i-C3H7Br, n-C3H7Br, n-C4H9Br, n-C8H17Br, n-C12H25Br, n-C18H37Br, PhCH2Br, and BrCH2(CH2)2CH2Br) followed by the cluster chlorination with sulfuryl chloride SO2Cl2 in acetonitrile. The process proceeds until the hydrogen atoms in the boron cluster are completely replaced with chlorine and completes within 60 h. It has been found that the melting point of salts ((C4H9)4N)[B10Cl9SR2] (R= i-C3H7, n-C3H7, n-C4H9, n-C8H17, n-C12H25, and n-C18H37) strongly depends on the length of the hydrocarbon chain of the substituent R.
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Features of the formation of zinc(II) and cadmium(II) complexes with the inner-sphere and outer-sphere position of the decahydro-closo-decaborate anion in the presence of azaheterocyclic ligands. Inorganica Chim Acta 2021. [DOI: 10.1016/j.ica.2021.120315] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Microplotter printing of planar solid electrolytes in the CeO 2-Y 2O 3 system. J Colloid Interface Sci 2021; 588:209-220. [PMID: 33388583 DOI: 10.1016/j.jcis.2020.12.052] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 12/14/2020] [Accepted: 12/16/2020] [Indexed: 12/12/2022]
Abstract
The formation process for planar solid electrolytes in the CeO2-Y2O3 system has been studied using efficient, high-performance, high-resolution microplotter printing technology, using functional ink based on nanopowders (the average size of crystallites was 12-15 nm) of a similar composition obtained by programmed coprecipitation of metal hydroxides. The dependence of the microstructure of the oxide nanoparticles obtained and their crystal structure on yttrium concentration has been studied using a wide range of methods. According to X-ray diffraction (XRD), the nanopowders and coatings produced are single-phase, with a cubic crystal structure of the fluorite type, and the electronic state and content of cerium and yttrium in the printed coatings have been determined using X-ray photoelectron spectroscopy (XPS). The results of scanning electron (SEM) and atomic force microscopy (AFM) have shown that the coatings produced are homogeneous, they do not contain defects in the form of fractures and the height difference over an area of 1 µm2 is 30-45 nm. The local electrophysical characteristics of the oxide coatings produced (the work function of the coating surface, capacitance values, maps of the surface potential and capacitive contrast distribution over the surface) have been studied using Kelvin-probe force microscopy (KPFM) and scanning capacitive microscopy (SCM). Using impedance spectroscopy, the dependence of the electrophysical characteristics of printed planar solid electrolytes in the CeO2-Y2O3 system on yttrium content has been determined and the prospects of the technology developed for the manufacture of modern, intermediate-temperature, solid oxide fuel cells have been demonstrated.
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Synthesis and structures of compounds [ML6][B10Cl10] (M = Co, Ni; L = CH3CN, DMF, DMSO) as precursors for synthesis of cobalt(II) and nickel(II) complexes with organic L ligands. J SOLID STATE CHEM 2021. [DOI: 10.1016/j.jssc.2021.121989] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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33
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Nucleophilic addition of amino acid esters to nitrilium derivatives of closo-decaborate anion. MENDELEEV COMMUNICATIONS 2021. [DOI: 10.1016/j.mencom.2021.03.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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34
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Zinc(II) and cadmium(II) complexes with the decahydro-closo-decaborate anion and phenyl-containing benzimidazole derivatives with linker N N or C N group. Polyhedron 2021. [DOI: 10.1016/j.poly.2020.114902] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Microplotter-Printed On-Chip Combinatorial Library of Ink-Derived Multiple Metal Oxides as an "Electronic Olfaction" Unit. ACS APPLIED MATERIALS & INTERFACES 2020; 12:56135-56150. [PMID: 33270411 DOI: 10.1021/acsami.0c14055] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Information about the surrounding atmosphere at a real timescale significantly relies on available gas sensors to be efficiently combined into multisensor arrays as electronic olfaction units. However, the array's performance is challenged by the ability to provide orthogonal responses from the employed sensors at a reasonable cost. This issue becomes more demanded when the arrays are designed under an on-chip paradigm to meet a number of emerging calls either in the internet-of-things industry or in situ noninvasive diagnostics of human breath, to name a few, for small-sized low-powered detectors. The recent advances in additive manufacturing provide a solid top-down background to develop such chip-based gas-analytical systems under low-cost technology protocols. Here, we employ hydrolytically active heteroligand complexes of metals as ink components for microplotter patterning a multioxide combinatorial library of chemiresistive type at a single chip equipped with multiple electrodes. To primarily test the performance of such a multisensor array, various semiconducting oxides of the p- and n-conductance origins based on pristine and mixed nanocrystalline MnOx, TiO2, ZrO2, CeO2, ZnO, Cr2O3, Co3O4, and SnO2 thin films, of up to 70 nm thick, have been printed over hundred μm areas and their micronanostructure and fabrication conditions are thoroughly assessed. The developed multioxide library is shown to deliver at a range of operating temperatures, up to 400 °C, highly sensitive and highly selective vector signals to different, but chemically akin, alcohol vapors (methanol, ethanol, isopropanol, and n-butanol) as examples at low ppm concentrations when mixed with air. The suggested approach provides us a promising way to achieve cost-effective and well-performed electronic olfaction devices matured from the diverse chemiresistive responses of the printed nanocrystalline oxides.
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Formation of oxidopolyborates in destruction of the [B11H14]– anion promoted by transition metals. Inorganica Chim Acta 2020. [DOI: 10.1016/j.ica.2020.119693] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Synthesis and structures of mono- and binuclear silver(I) complexes with triphenylphosphine and the dodecahydro-closo-dodecaborate anion. Polyhedron 2020. [DOI: 10.1016/j.poly.2020.114566] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Structures, magnetic properties, and EPR studies of tetranuclear copper(II) complexes [Cu4(OH)4L4]4+ (L = bpa, bipy) stabilized by anions containing decahydro-closo-decaborate anion. Polyhedron 2020. [DOI: 10.1016/j.poly.2020.114540] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract
Boron-cross-linked cobalt(II) pseudoclathrochelate was obtained by the template reaction of 2-acetylpyrazoloxime, phenylboronic acid, and a new DMF cobalt(II) solvato complex with a decachloro-closo-decaborate dianion. As confirmed by single-crystal X-ray diffraction, this complex crystallizes with two symmetry-independent cobalt(II) pseudoclathrochelate cations, one decachloro-closo-decaborate dianion, one benzene, one dichloromethane solvent molecule, and two molecules of DMF. The latter act as pseudocapping fragments to the monocapped tris-pyrazoloximate ligands by forming N-H···O hydrogen bonds with their pyrazole groups. The CoIIN6-coordination polyhedra adopt a nearly ideal TP geometry with distortion angles φ equal to 1.22(16) and 2.58(17)° for two symmetry-independent pseudoclathrochelate cations, both containing the encapsulated cobalt(II) ion in its high-spin state (Co-N 2.115(4)-2.198(3) Å). Magnetic properties of this complex were studied both by dc-magnetometry and by solution-state NMR spectroscopy to reveal a high magnetic anisotropy, thus suggesting a large magnetic susceptibility tensor anisotropy (25.8 × 10-32 m3 at 298 K) and a large negative zero-field splitting energy (-85 cm-1). The results of magnetometry studies in the ac magnetic field suggest a single molecule magnet behavior of this TP complex with an effective magnetization reversal barrier of approximately 130 cm-1. Its pseudocapping DMF molecules that form H-bonds with tris-pyrazoloximate fragments are easy to substitute by strong H-bond acceptors, such as chloride ions and di- and tetramethylureas, thus affecting the magnetic properties of a whole pseudomacrobicyclic paramagnetic system.
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Theoretical study of monocarbonyl derivatives of closo-borate anions [B H–1CO]– (n= 6, 10, 12): bonding and reactivity analysis. MENDELEEV COMMUNICATIONS 2020. [DOI: 10.1016/j.mencom.2020.01.029] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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41
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Complexation and exopolyhedral substitution of the terminal hydrogen atoms in the decahydro-closo-decaborate anion in the presence of cobalt(II). Polyhedron 2019. [DOI: 10.1016/j.poly.2019.01.051] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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42
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Electrophilicity of aliphatic nitrilium closo -decaborate clusters: Hyperconjugation provides an unexpected inverse reactivity order. J Organomet Chem 2018. [DOI: 10.1016/j.jorganchem.2018.06.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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43
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Sol-gel made titanium dioxide nanostructured thin films as gas-sensing materials for the detection of oxygen. MENDELEEV COMMUNICATIONS 2018. [DOI: 10.1016/j.mencom.2018.03.018] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Mechanism of generation of closo-decaborato amidrazones. Intramolecular non-covalent B–H⋯π(Ph) interaction determines stabilization of the configuration around the amidrazone CN bond. NEW J CHEM 2018. [DOI: 10.1039/c8nj01018h] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Three types of N(H)-nucleophiles were used to study the nucleophilic addition to the CN group of the 2-propanenitrilium closo-decaborate cluster giving N-closo-decaborato amidrazones.
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Solid-State Reactions of Eicosaborate [B20
H18
]2−
Salts and Complexes. Chemistry 2017; 23:16819-16828. [DOI: 10.1002/chem.201703285] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2017] [Indexed: 11/08/2022]
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Effective binding of perhalogenated closo -borates to serum albumins revealed by spectroscopic and ITC studies. J Mol Struct 2017. [DOI: 10.1016/j.molstruc.2017.03.059] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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closo-Dodecaborate Intercalated Yttrium Hydroxide as a First Example of Boron Cluster Anion-Containing Layered Inorganic Substances. Inorg Chem 2017; 56:3421-3428. [DOI: 10.1021/acs.inorgchem.6b02948] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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48
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Synthesis of New Bioinorganic Systems Based on Nitrilium Derivatives of closo-Decaborate Anion and meso-Arylporphyrins with Pendant Amino Groups. MACROHETEROCYCLES 2017. [DOI: 10.6060/mhc171254z] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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