ChemElectroChem最新文献

The front cover illustration depicts the electrochemical behavior of various stainless-steel (SUS) grades in coin cells using electrolyte formulations containing lithium hexafluorophosphate (LiPF6) and lithium bis(fluorosulfonyl)imide (LiFSI) salts. The presence of chlorine ions (Cl-) as impurities in the LiFSI salt promotes localized corrosion, leading to pitting and dissolution of SUS when the cell voltage approaches 4.2 V. Such dissolution behavior is influenced by multiple factors, with the specific SUS grade and the presence of surface coatings playing critical roles in determining corrosion resistance. More details can be found in the Research Article by Marian Cristian Stan, Isidora Cekic-Laskovic, and co-workers (DOI:10.1002/celc.202400632.

The Front Cover image showcases various inorganic materials suitable for use as solid-state electrolytes in all-solid-state potassium-ion batteries. The upper-left figure highlights potassium-ion conductivity plots, offering insights into potential high-performance inorganic solid-state electrolytes. The cover image was designed by Kanon Tanaka. Further details are available in the Perspective authored by Titus Masese and Godwill Mbiti Kanyolo (DOI: 10.1002/celc.202400598).

Electrochemical biosensors have been instrumental in early disease detection, facilitating effective monitoring and treatment. The emergence of graphene has significantly advanced sensor technology in various fields, including biomedicine, electronics, and energy. In this landscape, laser-induced graphene (LIG) has emerged as a superior alternative to conventional graphene synthesis methods. Its straightforward fabrication process and compatibility with wearable devices boost its practicality and potential for real-world applications. This review highlights the transformative potential of LIG in biosensing, showcasing its contributions to the development of next-generation diagnostic tools for early disease detection. An overview of the LIG synthesis process and its applications in detecting a wide array of biomarkers, from small molecules to large macromolecules, is provided. The integration of LIG biosensors into wearable devices are explored, highlighting their flexibility and potential for continuous, non-invasive monitoring of biomarkers. Additionally, this review addresses the current challenges in this field and discusses the future directions for the advancement of LIG-based biosensors in biomedical applications.

Recently, electrochemical methods have been harnessed as a transition metal-free strategy for borylation reactions in the synthesis of organoboron compounds. This article reviews the electrochemical borylation of C−C and C−Het bonds, offering a systematic discussion of C−C, C−N, C−O, and C−S bond borylation reactions. These transformations are applied to substrates including ammonium salts, aryl azo sulfones, carboxylic acids, arylhydrazines, nitroarenes, alcohols, and thioethers, showcasing broad compatibility. Additionally, the review discusses reaction mechanisms, scalability, and practical applications of these electrochemical strategies. The article concludes by outlining future research directions for electrochemical borylation reactions, aiming at expending their applications in incorporating boron into a wider array of organic compounds, including the challenging unactivated C−Het and C−F bond borylations.

To provide a solid reference for the design of novel perovskite-oxide electrocatalysts for efficient water splitting, the fundamental HER and OER mechanisms, synthetic methods, tuning strategies, and material properties have been demonstrated in this review. In addition, the main challenges in further improving the material stability and electrocatalytic water splitting efficiency of current perovskite-oxide electrocatalysts for practical applications have also been discussed in detail. More details can be found in the Review by Bolong Huang and co-workers (DOI: 10.1002/celc.202400648).

The spatially controlled, template-free, deposition of electroactive and biocompatible materials on 3D objects is of great interest for wireless cell stimulation intended for diverse applications ranging from electroceuticals to advanced sensor development. Bipolar electrochemistry provides the possibility of depositing electrically conducting polymers controlled through the (shaped) electric field distribution. A second advantage is that electrochemistry can be performed in electrolyte-free media potentially removing the “interfering” effect of added electrolyte. Here, poly(3,4-ethylenedioxythiophene) (PEDOT) films have been deposited on bipolar electrodes directly in ultrapure water. Significantly, the deposition patterns cannot be fully explained using a linear change in the solution-phase potential, which is a common assumption for bipolar electrochemical systems. 3D finite element modeling and diffusive mass transport considerations have been combined to map the electric field distribution in this very low conductivity medium and demonstrate that homogenous rather than heterogeneous electron transfer is likely to play an important role in polymer deposition. Moreover, modeling predictions were compared to electrochemical impedance and cyclic voltammetry results and non-linear behaviours qualitatively matched, through film capacitances, and deposition patterns. The proposed framework opens up significant opportunities for the template-free deposition of various electroactive materials on bipolar electrodes in low-conductivity solutions.

Potassium-ion batteries (KIBs) are increasingly attractive owing to their high voltage and projected low cost. However, the advancement of KIBs has been constrained by challenges related to electrolyte stability and interface compatibility. Traditional liquid electrolytes pose significant risks, including leakage and flammability, prompting a shift towards solid-state electrolytes, which offer improved energy density, safety and thermal stability. This Perspective explores the current state of inorganic solid-state electrolytes entailing oxides, chalcogenides, halides and hydrides. We delve into their recent advancements, identifying key challenges and future research opportunities, with the aim of advancing the development of high-performance all-solid-state potassium batteries.

Leveraging physicochemical advantages over lithium hexafluorophosphate (LiPF₆), lithium bis(fluorosulfonyl)imide (LiFSI) is being investigated as a conducting salt for lithium manganese-rich cathodes (LMR) and micro-crystalline silicon anodes (μ-Si). Nevertheless, its behavior towards the aluminum (Al) current collector and stainless-steel (SUS) coin cell parts limits its application under operating conditions requiring potentials higher than 3.9 V vs. Li|Li⁺. Using a mixture of organic carbonate-based solvents, various functional additives, and LiPF₆ lithium salt concentrations up to 1.0 M, the instability issue of the Al current collector in the presence of LiFSI is avoided. However, stainless-steel dissolution remains, being confirmed by both potentiodynamic measurements and SEM morphology investigations of the coin cell components after linear sweep voltammetry measurements carried out to 5.0 V. The results also indicate that the amount of stainless-steel dissolution is influenced by both the LiFSI amount in the electrolyte and the quality (grade) of stainless-steel used. Using Al-coated SUS 316L coin cell parts and/or high concentration electrolytes (HCE) with LiFSI (≈4 M LiFSI), the observed stainless-steel dissolution process can be fully avoided, allowing the evaluation of the electrochemical performance of LMR cathodes with μ-Si anodes in LiFSI-based electrolytes.

Sodium-ion batteries (SIBs) are an emerging next-generation technology for sustainable energy storage. In this study, the synthesis and performance of carbon anode materials for SIBs, produced via direct co-carbonisation of textile waste-derived hard carbon (HC) and pitch-derived soft carbon (SC) at various ratios, were investigated. It was found that, as the ratio of HC increased, the rate capacity of the composite carbon anode improved, with the best performing composite anode exhibiting a specific capacity of 334 mAh g⁻¹ at a current density of 50 mA g⁻¹ which exceeded the specific capacity of 100 %HC and 100 %SC. The co carbonisation of the HC with the SC is critical to ensure the stabilisation of the pitch composite with in the new composite anode. A detailed examination of morphology, microstructure and electrochemical properties is reported here.

During preconditioning of PtNiMo/C catalyst metal dissolution and redeposition takes place. At slow scan rates this leads to increased steady activity for oxygen reduction reaction (ORR). Furthermore, ionic liquids (IL) influence the activity of Pt-based catalysts and can alter the leaching of Pt-alloy catalysts. This study investigates the influence of ILs on the preconditioning of PtNiMo/C catalysts. Therefore, preconditioning parameters as well as the IL employed were varied. ILs with long side chains like [C8fC1][BETI] resulted in a spreading of the activity development during preconditioning over a longer cycle time and with damped amplitude for the activity changes. For shorter side chains like [BMIM][BETI] the development is like the pristine catalyst. Ex-situ and in-situ characterization revealed that [BMIM][BETI] leached fast to the electrolyte, which was not observed for the other ILs. Nevertheless, for all ILs a strongly reduced platinum leaching was observed. Even for the leached [BMIM][BETI] a stable wetting layer influencing the leaching seems to remain. Nevertheless, only for the other ILs where an immobilized bulk phase is remaining a difference in catalyst restructuring during the preconditioning is observed and a higher number of small sized Pt clusters and a lower amount of bigger Pt clusters resulted.