Journal of Solid State Electrochemistry最新文献

Respiratory syncytial virus (RSV) is responsible for outbreaks of bronchiolitis, bronchitis, and pneumonia and is effective and lethal in children under five years old. Current RSV detection methods are expensive, time-consuming, and require highly skilled personnel. Therefore, we developed a cost-effective impedimetric immunosensor for the detection of RSV based on a pencil graphite electrode (PGE) modified with a polymeric film derived from 3-amino phenylacetic acid. The current responses in the potassium ferricyanide and methylene blue solutions suggest the presence of unchanged carboxylic acid groups in the polymer. With a similar number of electrons involved in the first step of the reaction and electron/proton ratio to those proposed for aniline, a mechanism for electropolymerization was proposed. The immunosensor was assembled by activating the carboxyl groups via an EDC/NHS nucleophilic substitution reaction with the amino groups present in the anti-RSV monoclonal antibody (mAb). The detection was performed using electrochemical impedance spectroscopy, and the data were evaluated using equivalent circuits. The charge transfer resistance values increased as PGE was modified in the following order: PGE < PGE/polymer < PGE/polymer/mAb < PGE/polymer/mAb/virus. 100 ng of mAb was used, and the immobilization times for mAb and blocker were 3 h and 50 min, respectively. The response time for RSV immobilization was 30 min. The limit of detection was 22.54 PFU mL⁻¹, and the limit of quantification was 75.12 PFU mL⁻¹, with a linear range from 50 – 2000 PFU mL⁻¹, demonstrating that the proposed immunosensor is a viable alternative for the detection of RSV.

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As an electrochemical device that converts the chemical energy of fuel directly into electrical energy, the fuel cell is a new alternative technology that uses fuel from renewable sources and generates power for sustainable development and energy security. Among various types of fuel cells, the direct carbon fuel cell (DCFC) has higher efficiency because carbon fuel has higher energy density than liquid or gas fuel. However, the current development of DCFCs is still limited by the sluggish activity of the cathode reaction. In this study, a new composite cathode made of Gd_0.2Ce_0.8O_1.9 (GDC) and SrFe_1−xTi_xO_3–δ (SFT) is developed for a Nicotiana tabacum-derived carbon fuel-based DCFC. The structural, optical, and electrochemical properties of the materials are systematically evaluated. X-ray diffraction analysis results show a cubic structure of GDC and cubic perovskite phase of SFT in the sample, with crystallite sizes of 37 and 15 nm, respectively. Ultraviolet–visible spectroscopy reveals an indirect band gap which exhibits a red shift. Fourier transform infrared spectroscopy confirms the presence of Ce–O, Sr–Ti–O, and Fe–O functional groups in all the samples. Scanning electron microscopy analysis shows the morphology and particle size of the materials. The sample Gd_0.2Ce_0.8O_2-δ–SrFe_0.96Ti_0.04O_1.9 exhibits the highest electrical conductivity of 4.96 S cm⁻¹ in an oxygen atmosphere at 600 °C and a higher power density of 40 mW cm⁻² at 600 °C compared to other samples using Nicotiana tabacum carbon fuel. These findings indicate that the developed composite cathode is an efficient cathode for low-temperature DCFCs.

Electrochemical impedance spectroscopy (EIS) was employed in an attempt to gain insight into the mechanisms of ethyl 2-cyanoacrylate (ECA) curing (polymerisation) and bonding on aluminium alloy 2024 metal. EIS can detect ionic movement, adsorption processes, charge transfer and storage occurring at an adhesive/substrate interface and/or in a bulk bond line during curing. Low-frequency capacitance measurements demonstrated sensitivity to surface polymerisation reactions and were modelled using an equivalent circuit model with two time constants in series. At a frequency of 1 kHz, changes in the dielectric polymer could be readily followed with time, confirmed by employing a crown ether to accelerate the polymerisation process. Hydrolytic degradation of poly-ECA bonds at a stainless steel interface was also investigated. An equivalent circuit model containing a number of circuit components comprising pore, charge transfer and diffusional impedances, along with polymer film, double layer and diffusional capacitances (represented by constant phase elements), was developed. Three regions were identified in the frequency domain and ascribed to processes taking place at the polymer/electrolyte and polymer/metal oxide interfaces. In short, EIS can be employed to follow the rate of polymerisation of ethyl-2-cyanoacrylate and also the degradation of the resulting polymer in saline solution.

This research innovatively produced polyaniline-coated carbon cloth (PANI@CC) using an electrochemical deposition process, highlighting the impact of carbon cloth substrate characteristics on the performance of symmetric supercapacitors in a coin cell setup. The study compared the electrochemical performance of hydrophilic and hydrophobic, soft, and hard carbon cloth substrates through cyclic voltammetry, galvanostatic charge–discharge, and electrochemical impedance spectroscopy. The PANI@0-N (hydrophilic soft carbon cloth) substrate showcased superior electrochemical properties, achieving a maximum specific capacitance of 113.3 F g⁻¹ at a current density of 0.1 A g⁻¹, with a noteworthy rate capability of 88.6%. After 2000 galvanostatic charge–discharge cycles at 1 A g⁻¹, the developed symmetric coin cell supercapacitor retained 74% of its initial capacitance, demonstrating notable durability and efficiency. This underscores the significance of substrate selection in the direct synthesis approach for optimizing supercapacitor performance, making the PANI@0-N-based coin cell a promising option for supercapacitor applications.

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We report the comparison of multiple acetylene black (AB) rigid carbon composites for electrochemical purposes exploring several binders, including one (polyurethane) from a renewable source of castor oil. The acetylene black–based composites presented less roughness and increased surface homogeneity evinced by AFM and SEM images within the micrometer range. Contact angle analysis and Raman spectra confirmed a high degree of surface functionalization associated with structural defects on AB even when the base conductive material is associated with a non-conductive binder. The acetylene black-castor oil electrode presented superior performance (lower resistance to charge transfer and increased peak currents) when compared to its graphite counterparts regardless of the mechanical activation. The proposed electrode presented an excellent electrochemical performance in analyzing contaminants of emerging concern when compared to glassy carbon electrodes. The sustainable aspect of this work is evinced considering the room temperature synthesis, low cost of the AB, and renewable castor oil binder source.

This study presents a novel sensor for the detection of levodopa (LD) utilizing a glassy carbon electrode modified with a TiO₂/MWCNT nanocomposite. Structural analysis confirmed the suitability of the nanocomposite for sensor fabrication, revealing enhancements in effective surface area and sensitivity. Characterization studies employing SEM, EDX, and FT-IR analyses provided insights into the composition and morphology of the modified electrode. The sensor exhibited exceptional performance metrics, including a wide linear detection range (19.6–545 µM), low detection limit (2.51 µM), high repeatability (78.1%), and remarkable average recovery rates in real samples (99.86%). Minimal interference from interfering species further demonstrated its practical utility. Moreover, the sensor’s direct applicability in diverse sample matrices, without the need for sample separation, highlighted its versatility and convenience. Comparative analysis revealed the sensor’s performance to be comparable to established methods, offering a cost-effective and streamlined approach to LD measurement. Overall, the modified glassy carbon electrode with TiO₂/MWCNT nanocomposite presents a clear, suitable, and stable electrocatalytic response, promising significant advancements in biosensing technology for LD detection.

Martensitic and super martensitic stainless steels are widely used in the oil and gas industry for general corrosion mitigation in the presence of sweet corrosion (CO₂) and sour corrosion (H₂S), providing a cost-effective alternative to more expensive exotic corrosion-resistant alloys. Martensitic stainless steel is an approved material for construction when selecting tubular CO₂ injection wells. This work aims to review the published literature on the subject of the operation limits of martensitic stainless steel and super martensitic stainless steel in high temperatures and high pressure under corrosive environments. Stress corrosion cracking (SCC) and sulfide stress corrosion cracking (SSCC) mechanisms on martensitic and super martensitic stainless steel surfaces are thoroughly analyzed. In this review paper, we have analyzed the factors that play a crucial role in passive film growth and passivity breakdown. The present work is to review the state of the art of mechanism responsible for SCC and SSCC susceptibility in different modified martensitic stainless steel materials, which are applied to the industry and lab scale. We have reviewed the effect of different concentrations of molybdenum content on SCC and SSCC susceptibility of conventional martensitic stainless steel, modified martensitic stainless steel, and super martensitic stainless steel. The effect of tempering temperature on the SCC and SSCC performance of the martensitic and super martensitic stainless steel was also studied. We also studied the effect of different concentrations of chromium on the improved corrosion-resistant properties and stability of passivation film.