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Electroplating of 3D Printed Electrodes for Selective Electrochemical Reduction of C02
Vaněčková, Eva; Bouša, Milan; Shestivska, Violetta; Kubišta, Jiří; Rathouský, Jiří; Sebechlebská, Táňa; Kolivoška, Viliam
2021 - English
In this work, computer assisted design and fused deposition modelling 3D printing are\nemployed to devise and manufacture electrodes from polylactic acid-carbon nanotube\nconductive composite. Electrodes are further modified by copper electroplating to prepare\ncatalysts for the electrochemical reduction of carbon dioxide. Scanning electron microscopy\nand energy dispersive X-ray analysis are used to inspect the surface morphology and chemical\ncomposition of obtained catalysts. Cyclovoltammetric investigations reveal that the copper\nelectroplating leads to the increase of electrode activity by three orders of magnitude.
Keywords:
3D printing; electrochemical reduction of carbon dioxide; electroplating
Available on request at various institutes of the ASCR
Electroplating of 3D Printed Electrodes for Selective Electrochemical Reduction of C02
In this work, computer assisted design and fused deposition modelling 3D printing are\nemployed to devise and manufacture electrodes from polylactic acid-carbon nanotube\nconductive composite. ...
ELECTROCHEMICAL STUDY OF CuSCN INORGANIC HOLE-TRANSPORT MATERIAL FOR SOLAR CELLS PREPARED BY ELECTRODEPOSITION FROM AQUEOUS SOLUTION
Vlčková Živcová, Zuzana; Mansfeldová, Věra; Bouša, Milan; Kavan, Ladislav
2021 - English
A comparative study is reported for electrodeposited copper(I) thiocyanate layers (ca. 500 nm) on two types of conductive/semiconductive substrates: i) carbon (boron-doped diamond_BDD, glass-like carbon_GC), and ii) carbon-free F-doped SnO2 conducting glass (FTO). SEM and Raman evidence that electrodeposition from aqueous solution results in homogenous CuSCN layers with dominant thiocyanate ion bounded to copper through its S-end (Cu−SCN bonding), as in spin-coated CuSCN layers. Electrochemical impedance spectroscopy (EIS) confirms the p-type semiconductivity of layers with a flatband potential from 0.1 to 0.18 V vs. Ag/AgCl depending on the substrate type, and the acceptor concentration (NA) of 5 x 1020cm-3 in all cases. The flatband potentials determined from Mott-Schottky plots (EIS) are in good agreement with the Kelvin probe measurements. The blocking quality of CuSCN layers was tested using Ru(NH3)63+/2+ redox probe. CuSCN deposited on BDD substrate exhibits better blocking properties compared to CuSCN deposited on FTO.
Keywords:
electrodeposition; CuSCN; hole transport material
Available in digital repository of the ASCR
ELECTROCHEMICAL STUDY OF CuSCN INORGANIC HOLE-TRANSPORT MATERIAL FOR SOLAR CELLS PREPARED BY ELECTRODEPOSITION FROM AQUEOUS SOLUTION
A comparative study is reported for electrodeposited copper(I) thiocyanate layers (ca. 500 nm) on two types of conductive/semiconductive substrates: i) carbon (boron-doped diamond_BDD, glass-like ...
Comparison of the Covalent Laccase Immobilization at Amino- and Carboxylfunctionalized Mesoporous Silica, Glassy Carbon, and Graphite Powders using Different Coupling Agents for Optimal Biosensor Preparation
Tvorynska, Sofiia; Barek, J.; Josypčuk, Bohdan
2021 - English
In order to find the most suitable immobilization protocol, a comparison of three strategies\nbased on the application of –NH2 and –COOH functionalized supports with the different\nactivation agents (glutaraldehyde and carbodiimide) have been conducted for the covalent\nenzyme (laccase) attachment. Two kinds of the supports, namely mesoporous silica (SBA−15,\nMCM−41) and carbonaceous (glassy carbon, graphite) powders, have been used. It was found\nthat a biosensor consisted of tubular detector of silver solid amalgam as a working electrode\nand the enzymatic mini-reactor with laccase covalently attached to glutaraldehyde activated\n–NH2 functionalized MCM−41 shows the best results regarding sensitivity and stability for\ndopamine detection.
Keywords:
Covalent enzyme immobilization; Support surface functionalization; Laccase
Available on request at various institutes of the ASCR
Comparison of the Covalent Laccase Immobilization at Amino- and Carboxylfunctionalized Mesoporous Silica, Glassy Carbon, and Graphite Powders using Different Coupling Agents for Optimal Biosensor Preparation
In order to find the most suitable immobilization protocol, a comparison of three strategies\nbased on the application of –NH2 and –COOH functionalized supports with the different\nactivation agents ...
EPR/UV-VIS-NIR Spectroelectrochemical Examination of the Association Properties of Thienoacene-Bridged Tetrathiafulvalenes Supported by DFT Calculations
Lušpai, Karol; Rapta, P.; Zalibera, M.; Darvasiová, D.; Lukeš, V.
2021 - English
This work was focused on the EPR/UV-VIS-NIR spectroelectrochemical examination of\nassociation properties of radical cations electrochemically produced from tetrathiafulvalene\n(TTF) derivatives, in relation to the molecular structure, mainly the number and orientation of\nthiophene rings in the spacer between fulvalene redox centers. Results from EPR/UV-VIS-NIR\nspectroelectrochemistry were supported by DFT calculations.
Keywords:
Tetrathiafulvalene; EPR/UV-VIS-NIR spectroelectrochemistry; Cyclic voltammetry
Available on request at various institutes of the ASCR
EPR/UV-VIS-NIR Spectroelectrochemical Examination of the Association Properties of Thienoacene-Bridged Tetrathiafulvalenes Supported by DFT Calculations
This work was focused on the EPR/UV-VIS-NIR spectroelectrochemical examination of\nassociation properties of radical cations electrochemically produced from tetrathiafulvalene\n(TTF) derivatives, in ...
UV-Vis and IR Spectroelectrocbemistry of Copper Complexes and Bioactive Compounds
Sokolová, Romana; Obluková, Michaela; Sýs, M.; Mikysek, T.; Wantulok, J.; Nycz, J. E.; Degano, I.
2021 - English
The interpretation of the change of absorption spectrum of an oxidized and reduced molecule\nrecorded during the electron transfer is an efficient tool for the determination of oxidation or\nreduction mechanism. This technique provides the information about the electroactive\nchromophore and is performed in two regimes of electrochemical measurement, cyclic\nvoltammetry and chronoamperometry, respectively. This approach was successfully applied to\nstudy the fundamental electrochemical behavior of recently synthesized copper complexes\nproviding biomimetic activity, ofpolyphenolic bioactive compounds, and also for the reduction\nof halogenated phenanthrolines. The identification of redox products was done by\nchromatographic techniques as HPLC-DAD and HPLC-ESI-MS/MS.
Keywords:
Copper complexes; Catechol; spectroelectrochemistry
Available on request at various institutes of the ASCR
UV-Vis and IR Spectroelectrocbemistry of Copper Complexes and Bioactive Compounds
The interpretation of the change of absorption spectrum of an oxidized and reduced molecule\nrecorded during the electron transfer is an efficient tool for the determination of oxidation or\nreduction ...
Ion Transfer Voltammetry across the Polarized Ionic Liquid/Water Interface: Base for Electrochemical Sensors
Langmaier, Jan; Samec, Zdeněk
2021 - English
Some electrochemical techniques such as voltammetry at the polarized interfaces between two\nimmiscible electrolyte solutions (ITIES) represent interesting alternatives to classical\nelectrochemistry. The benefit of the ion transfer voltammetry lies in the possibility of detection\nof ionic species which are not otherwise redox active. The methodology enables apart of direct\ndetermination of ionic samples (including pharmaceutical and clinical ones) also to monitor\nreaction processes (acido-basic, enzymatic, etc.), determination of reaction substrates and\nproducts in one experimental step, evaluation of reaction and transport kinetics, and estimation\nof lipophilicity of involved species.
Keywords:
ion transfer voltammetry; electrochemical detection; ionic liquid
Available on request at various institutes of the ASCR
Ion Transfer Voltammetry across the Polarized Ionic Liquid/Water Interface: Base for Electrochemical Sensors
Some electrochemical techniques such as voltammetry at the polarized interfaces between two\nimmiscible electrolyte solutions (ITIES) represent interesting alternatives to classical\nelectrochemistry. ...
The use of Boron Doped Diamond Electrode for Determination of 5-hydroxyindoleacetic Acid
Hrdlička, Vojtěch; Navrátil, Tomáš
2021 - English
A new method for voltammetric determination of clinical biomarker 5-hydroxyindoleacetic\nacid (HIAA) at the boron-doped diamond electrode (BDDE) was developed. Anodically and\ncathodically pretreated BDDEs were tested in the pH ranges from 1 to 12, pre-treatment at\n+2.0V/60 s, and pH 3 was found to be the optimum.\nThe optimum square wave voltammetry (SWV) parameters were: f = 12 Hz, amplitude 60\nmV, and potential step 4 mV. SWV concentration dependency was constructed in the range\nfrom 0.1 to 100 μmol L−1, limits of determination and detection were 0.3 and 0.1 μmol L−1,\nrespectively. HIAA oxidation electrode process at BDDE was diffusion-controlled, as\nuncovered by cyclic voltammetry. Interestingly, HIAA peak potential was constant in various\nranges of pH, indicating a non-Nernstian behavior at the BDDE, in contrast to a previously\npublished electrooxidation mechanism consisting of a coupled H+/e− transfer.
Keywords:
boron-doped diamond electrode; 5-hydroxyindoleacetic acid; square wave voltammetry
Available on request at various institutes of the ASCR
The use of Boron Doped Diamond Electrode for Determination of 5-hydroxyindoleacetic Acid
A new method for voltammetric determination of clinical biomarker 5-hydroxyindoleacetic\nacid (HIAA) at the boron-doped diamond electrode (BDDE) was developed. Anodically and\ncathodically pretreated ...
Determination of Selected Drugs using 3D Printed Electrodes
Choińska-Mlynarczyk, Marta; Hrdlička, Vojtěch; Navrátil, Tomáš
2021 - English
The main aim of this research was to develop a new method for voltammetric determination of\npopular antidepressants, analgesics, and illicit drugs using a laboratory-made 3D printed\nelectrode and to compare the achieved results with those registered using a commercially\navailable glassy carbon electrode. These experiments represent the first step in the development\nof a method applicable in clinical and forensic praxis for the rapid and inexpensive\ndetermination of commonly misused groups of biologically active compounds.
Keywords:
analgesics; antidepressants; biologically active compounds
Available on request at various institutes of the ASCR
Determination of Selected Drugs using 3D Printed Electrodes
The main aim of this research was to develop a new method for voltammetric determination of\npopular antidepressants, analgesics, and illicit drugs using a laboratory-made 3D printed\nelectrode and to ...
Rozdíly v elektrochemické redukci jedno- a vícejaderných acylgermanů
Liška, Alan; Frühwirt, P.; Haas, M.; Ludvík, Jiří; Gescheidt-Demmer, G.
2021 - Czech
Acylgermany představují pestrou třídu organoprvkových sloučenin, které se vyznacuJI\npozoruhodnými fotochemickými vlastnostmi, laditelnými zavedením různých typů periferních\nsubstituentů, jejich počtem, polohou, případně způsobem přemostění. Většina známých\nderivátů podléhá vlivem DV-záření nebo dokonce krátkovlnějšího viditelného světla\nhomolytickému štěpení vazby C-Ge za vzniku radikálů. Některé (např. Ivocerin®) se proto již\ndelší dobu používají v zubní medicíně jako fotoiniciátory polymerizace při přípravě bílých\nnetoxických zubních výplní. Příslušné mechanismy reakcí uplatňujících se v praxi jsou v\nliteratuře dobře dokumentovány. Vzhledem k tomu, že penetrační hloubka\nelektromagnetického záření je nepřímo úměrná jeho energii, existuje snaha nalézt další\nderiváty, které budou efektivně štěpeny světlem o co největší vlnové délce. Kromě absorpčních\nspekter a teoretických výpočtů molekulových vlastností (ionizační energie, elektronové\nafinity) se při hledání nových látek s výhodou uplatňují elektrochemické metody, protože\npoloha prvního redukčního potenciálu (resp. rozdíl mezi prvním redukčním a prvním\noxidačním potenciálem) koreluje se schopností molekuly absorbovat světlo a zaujímat vyšší\nexcitované stavy, což se projeví jako poloha dlouhovlnného pásu UV-vis spekter. Ail the studied compounds accept first electron under formation a stable anion radical. The\ncorresponding reduction potentials in aprotic media depend on electronic (inductive,\nmesomeric) properties of the substituents, their number, and position. Here, aromatic acyl group\n(benzoyl group with various substitution on aromatic ring) is the principal substituent. The\nredox properties of presented organoelement compounds with central heteroatom Ge (Si, Sn)\nare controlled by peripheral carbonyl groups (in role of redox centers), their number, and\naromatic ring substitution. The measured first reduction potentials E1 values are found in wide\nrange (> 900 mV) due to the fact that the redox centers are carbony 1 groups connected through\nheteroatom in case of acylgermanes, while for di- and trinuclear derivatives (which are\nmolecules with multiple redox centers) the easiest reducible center is the bridging aromatic unit\ninfluenced by the closest carbonyl groups. Thus, it is possible to distinguish both groups ofnonequivalent\ncarbonyl substituents.
Keywords:
Acylgermanes; Electrochemistry; Voltammetry
Available on request at various institutes of the ASCR
Rozdíly v elektrochemické redukci jedno- a vícejaderných acylgermanů
Acylgermany představují pestrou třídu organoprvkových sloučenin, které se vyznacuJI\npozoruhodnými fotochemickými vlastnostmi, laditelnými zavedením různých typů periferních\nsubstituentů, jejich ...
A comparative study of covalent glucose oxidase and laccase immobilization techniques at powdered supports for biosensors fabrication
Tvorynska, Sofiia; Barek, J.; Josypčuk, Bohdan; Nesměrák, K.
2020 - English
In order to develop the optimal strategy and to deepen the knowledge in the field of enzyme immobilization, three different techniques of covalent binding for two enzymes (glucose oxidase and laccase) at powdered surfaces were compared. Immobilization protocol was optimized by changing supports (two mesoporous silica powders (SBA−15, MCM−41) and a cellulose powder), the functionalized\ngroups introduced at support surfaces (−NH and −COOH), and the methods of activation (glutaraldehyde and carbodiimide). Amino and carboxyl functionalized mesoporous silica and cellulose powders\nwere prepared by silanization using (3-aminopropyl)triethoxysilane and carboxyethylsilanetriol, respectively. It was found that coupling of both enzymes by their –NH groups through glutaraldehyde to -NH functionalized supports, in particular SBA15−NH and cellulose−NH for glucose oxidase, MCM41−NH for laccase, showed the highest activity and the best stability.
Keywords:
biosensors; covalent immobilization; enzymatic reactor
Fulltext is available at external website.
A comparative study of covalent glucose oxidase and laccase immobilization techniques at powdered supports for biosensors fabrication
In order to develop the optimal strategy and to deepen the knowledge in the field of enzyme immobilization, three different techniques of covalent binding for two enzymes (glucose oxidase and laccase) ...
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