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Aiming to advance the technical maturity of CO2 electrolysis to formic acid, various gas diffusion layers (GDLs) are investigated for their suitability as carbon‐based substrate for gas diffusion electrodes (GDEs) and their effect on the electroreduction of CO2 to formate. Particular attention lies on the elucidation for the effect of the GDL thickness, hydrophobic treatment, and presence of a microporous layer (MPL) on the GDE performance in terms of Faradaic efficiency. Based on the investigation it is found that the GDL thickness has no discernible influence on the Faradaic efficiency, while a GDE with a hydrophobic treatment of 10 % PTFE outperforms a GDE based on a GDL with 30 % PTFE. Furthermore, the presence of a MPL is found to be of marked importance to achieve relevant current densities given its effect on the focus of the catalyst layer on the GDE surface after spray coating, the wetting, and the electrical conductivity. [ABSTRACT FROM AUTHOR]

Abstract Aiming to advance the technical maturity of CO2 electrolysis to formic acid, various gas diffusion layers (GDLs) are investigated for their suitability as carbon‐based substrate for gas diffusion electrodes (GDEs) and their effect on the electroreduction of CO2 to formate. Particular attention lies on the elucidation for the effect of the GDL thickness, hydrophobic treatment, and presence of a microporous layer (MPL) on the GDE performance in terms of Faradaic efficiency. Based on the investigation it is found that the GDL thickness has no discernible influence on the Faradaic efficiency, while a GDE with a hydrophobic treatment of 10 % PTFE outperforms a GDE based on a GDL with 30 % PTFE. Furthermore, the presence of a MPL is found to be of marked importance to achieve relevant current densities given its effect on the focus of the catalyst layer on the GDE surface after spray coating, the wetting, and the electrical conductivity.

One challenge in capitalizing on the affordability, sustainability, and accessibility of biohybrid solar energy conversion, including devices based on Photosystem I (PSI), is the identification of metal‐free electrode materials to replace the inorganic substrates commonly found in solar cell development. Herein, commercially available Toray carbon paper (CP) is investigated as a high surface area, carbon electrode for the development of photoactive bioelectrodes consisting of PSI and poly(3,4‐ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS). Mediated anodic photocurrent is achieved at both PSI multilayer and PSI–polymer composite films on CP electrodes subjected to flame pretreatment. Film preparation is optimized by utilizing potential sweep voltammetry in place of potentiostatic conditions for polymerization. The optimized PSI–PEDOT:PSS films achieve a threefold increase in polymer growth under potential sweep conditions, quantified through net charge consumed during electropolymerization, resulting in a fourfold increase in photocurrent density (−53 vs −196 nA cm−2). The ability to prepare photoactive PSI‐polymer films on metal‐free CP electrodes opens the door to a rapidly scalable system for biohybrid energy production ultimately leading to more affordable, sustainable, and accessible energy. [ABSTRACT FROM AUTHOR]

The continuous monitoring of antipsychotic drug release in the patient undergoing treatment is significant for dose monitoring. Hence, as a part of treatment, frequent blood tests are required to detect the drug level. In this context, the development of a miniaturized POC (Point-of-Care) Electrochemical sensing platform plays a significant role. The present work demonstrates the realization of a paper-based electrochemical sensing device for sensing of antipsychotic drug Clozapine (CLZ). A commercial Toray paper was used as a base electrode that showed high conductivity, mechanical strength, and gas permeability, hence appropriate for electrochemical sensing. Toray fibrous carbon electrodes were used for the sensing of CLZ. The CO 2 laser system with optimized speed (6.5 %) and power (4.5 %) was efficiently used to fabricate a simple, low-cost, and miniaturized Toray paper electrochemical device (TPED). The electrode surface was characterized using scanning electron microscopy, which showed a high porous gas diffusion layer with denser carbon. Cyclic Voltammetry (CV) and Chronoamperometry (CA) techniques were used to study the electrochemical characterization of the CLZ. The analytical performance of TPED was validated by sensing various concentrations of CLZ in a linear range from 0.5 µM to 5 µM with a Limit of detection (LoD) of 0.5 µM and a Limit of Quantification (LoQ) of 1.69 µM using cyclic voltammetry and the linear from 0.5 µM to 5 µM with a limit of detection (LoD) of 0.01 µM and Limit of Quantification (LoQ) of 0.05 µM using chronoamperometry techniques. Furthermore, the interference mitigation of TPED was examined with other biomolecules. Finally, the practicability of TPED was tested by performing a real sample analysis in blood serum. Based on the analytical performance, it was confirmed that the fabricated device has the ability to be applied in biomedical applications for drug sensing in point-of-care testing. [Display omitted] • Novel Miniaturized Toray paper-based device for clozapine detection is presented. • The device was characterized by various electrochemical techniques. • A Linear concentration range of 0.5 µM to 5 µM was achieved. • LOD and LOQ of 0.5 µM and 0.69 µM, respectively were obtained. • Serum sample was used for real sample analysis and upto 98 % efficacy obtained. [ABSTRACT FROM AUTHOR]

Twenty two carbon materials of different origins (e.g., graphite, graphene, carbon black, hydrochars, activated carbons, carbon nanotubes and nanofibers) and with varied physicochemical characteristics (e.g., electrical conductivity, structural order, surface functionalization, porosity) were investigated as cathodes in the electrochemical production of hydrogen peroxide. A screening of the electrocatalytic performance was carried out in 0.2 cm2 (inks casted on a glassy carbon) and 4 cm2 electrodes (Toray paper). The highest H 2 O 2 production yields were obtained for carbon nanotubes and carbon nanofibers, outperforming common carbon benchmarks for this application -i.e., carbon black, carbon felt-. Furthermore, a good catalytic activity was obtained with low-cost and disordered carbon cathodes with moderate electrical conductivity and density of structural defects (e.g., nanoporous carbons), both in terms of overall production rate, selectivity and energy consumption. Data also revealed that the H 2 O 2 production yield and the faradaic efficiency are closely related to the structural parameters of the carbon materials (i.e., density of structural defects), rather than to the electrical conductivity, composition or porous features. An A D /A G threshold value of 1.5 can be used to discriminate the electrocatalytic activity of carbon cathodes for the production of H 2 O 2 through a 2e-ORR, in terms of high production rates and good faradaic efficiencies. [Display omitted] [ABSTRACT FROM AUTHOR]

3D printing technology based electrochemical device can provide ease of fabrication, cost effectiveness, rapid detection and lower limit of detection. Herein, a novel, customized, portable and inexpensive 3D printed electrochemical device, has been presented. Fibrous carbon Toray paper, deposited with gold nanoparticles through electrodeposition, used as a working electrode which Further device was tested with 1 mM sodium hypochlorite using cyclic voltammetry (CV) and square wave voltammetry (SWV) in 0.1 M PBS. Hypochlorite has a pivotal role in supporting the growing chemical and paper industries and finds diverse uses in several clinical applications. It is primarily used for disinfecting food, water and surfaces. The scan rate study was carried out from 20 mVs−1 to 250 mVs−1 using cyclic voltammetry technique. The diffusion coefficient obtained from scan rate effect was 1.39 × 10−6 cm2s−1. The concentration range was evaluated with SWV technique, in a linear range of 0.6 μM–40 μM, with a detection limit of 0.7 μM. The device was further analyzed to ensure non-interference from co-existing chemicals like sodium chloride, potassium nitrate, sodium carbonate, sodium nitrite. Real sample analysis was done with sea, artificial sea and tap water with impressive recovery values. In summary, the developed working electrode can be customized and modified based on testing analyte; thus, the proposed device can be used for various other biochemical analytes. [Display omitted] • Miniaturized 3D printed electroanalytical device was fabricated. • Gold nanoparticles were electrodeposited on Toray paper used as working electrode. • 1 mL of the sample was used throughout all analysis. • Lower limit of detection 0.07 μM was obtained using the device. • Hypochlorite detection in sea, artificial sea and tap water samples was carried out. [ABSTRACT FROM AUTHOR]

Abstract: The performance of the fuel cell electrode depends on many factors: types of materials and their properties, composition, process parameters and fuel cell operation conditions. In the present paper, cathode electrode performance in a PEM fuel cell as a function of Teflon concentration in the substrate materials and in micro-layer carbon, pore former in the micro-layer, amount of carbon used in the diffusion layer and Platinum & Nafion loading in the catalyst layer are studied. These six factors each at two levels are considered. A full factorial design would have required 26, i.e., 64 experiments to be carried out. With the use of Taguchi method, L12 designs, the number of experiments can be reduced to 12. The electrode current density values are taken as responses for the analysis. Statistical sensitivity analysis (ANOVA analysis) is used to compute the effects and the contributions of the various factors to the fuel cell electrode. Some graphic representations are employed in order to display the results of the statistical analysis made for different current values. The behavior of cathode PEM fuel cell electrode was studied using humidified hydrogen and compressed air. The present paper examines the six main factors and their levels responsible for altering the performance particularly when the fuel is operated under ambient pressure. [Copyright &y& Elsevier]