ChemElectroChem最新文献

Microfluidic technology has exhibited remarkable potential and significance in the precise preparation of multifunctional nanomaterials. Thanks to its small reaction volume and superior hydrodynamic control, this technology has emerged as an essential tool for synthesizing multifunctional nanomaterials with precisely tunable microstructures and morphologies. This paper reviews the latest advancements in the controllable synthesis of metal nano-electrocatalysts utilizing microfluidic technology. Firstly, it systematically elucidates the fundamental principles of microfluidic synthesis technology and its distinctive parameter control strategies. Subsequently, it delves deeply into the mechanism of reaction enhancement in the synthesis process of metal nanoparticles in the microfluidic environment. Through the analysis of specific cases, the extensive application prospects and distinctive advantages of the microfluidic system in the preparation of nano-electrocatalysts have been further elucidated. Finally, it summarizes and looks forward to the challenges and future development directions that microfluidic technology faces in the synthesis of nano-electrocatalysts. This review aims to provide valuable insights into the application of microfluidic synthesis technology in the morphology design and technological innovation of electrocatalysts.

This work presents the synthesis, characterization, and application of a series of aprotic and protic acetate-based ionic liquids (AcILs). These cost-effective ILs can be obtained through a simple synthesis and display good transport and thermal properties. When used as electrolytes in electrical double-layer capacitors (EDLC) they enable the fabrication of devices with an operating voltage as high as 1.8 V, which display very good cycling and float stability. The performance of these devices can be tuned by adjusting the water content of the ILs. Notably, EDLCs containing AcILs can also be realized using aluminum current collectors.

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.

Ammonia is a widely produced chemical globally, primarily used in fertilizers and chemical products. Recently, it has gained attention as a green hydrogen carrier due to its high hydrogen content and energy density. However, the conventional Haber-Bosch process for ammonia synthesis is energy-intensive, requiring high temperatures and pressures. Also, it is a significant source of CO₂ emissions. To address these environmental concerns, the electrochemical nitrate reduction reaction (NO₃RR) has emerged as a promising approach for green ammonia production, utilizing nitrate from wastewater and renewable energy sources. While most previous research focuses on cathodic ammonia production, it needs to emphasize the importance of optimizing anodic reactions in NO₃RR systems to reduce energy consumption and improve efficiency. The conventional oxygen evolution reaction (OER), typically coupled with NO₃RR, is kinetically slow and requires a high standard potential. Therefore, alternative anodic reactions with lower standard potentials not only save energy but also yield valuable byproducts. Furthermore, coupling NO₃RR with anodic reactions like zinc oxidation allows for power generation, where a positive cell potential indicates spontaneous reactions. This dual approach, energy saving and generation, opens new pathways for sustainable ammonia production, reducing overall energy demands while supporting the shift toward green ammonia systems.

In this study, ZnO nanorods (ZnONR) were directly grown on carbon fiber paper (CFP), followed by the uniform chemical deposition of CuO nanowires (CuONW) and subsequent hydrothermal synthesis of Ag nanoparticles (AgNP) to form the ternary composite electrode AgNP-CuONW/ZnONR@CFP. When the prepared electrodes were investigated as a non-enzyme biosensor, two distinct and separated differential pulse voltammetric peaks for puerarin (PU) and daidzein (DAI) were observed, indicating that the simultaneous and selective detection of both isoflavones was feasible. The sensor exhibited a linear response across a broad concentration range of 0.01 to 30 μmol/L for puerarin (PU) and 0.05 to 15 μmol/L for daidzein (DAI), with detection limits of 4.0 nmol/L for PU and 17.8 nmol/L for DAI, respectively. Additionally, when used to detect puerarin (PU) and daidzein (DAI) in traditional Chinese medicine samples, the sensor performed excellently, yielding results that consistent with those obtained from high-performance liquid chromatography (HPLC) analysis.

Electrochemical CO₂ conversion is an important strategy to produce high-value carbon-containing molecules, such as ethylene and ethanol. Despite huge progress in recent years concerning CO₂ reduction catalyst development with increased selectivity, high selectivity for C₂₊ products at high current densities is still a challenge. We report the development and optimization of a new surface Al-rich Cu/CuO_x catalyst with high selectivity for C₂₊-products at high current densities of up to −800 mA cm⁻². We integrated the corresponding catalyst-modified gas-diffusion electrode into a second flow-through electrolyzer, which was connected to a first flow-through electrolyzer comprising a highly CO-selective Ni−Cu dual-atom N-doped carbon catalyst. The enrichment of the CO₂ stream with CO generated at a current density of −400 mA cm⁻² in the first electrolyzer increased the production rate of ethanol formation at the Al-rich Cu/CuO_x catalyst at a current density of −300 mA cm⁻² by 28 %, while maintaining the production rate of ethylene. Thereby, the overall yield of C₂₊-products obtained by CO₂ reduction was significantly increased.

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.

Despite the commercialization of flow batteries, little is known about how much electrode treatment methods affect individual electrode overpotential contributions. Thermal oxidation is one of the most common electrode treatment methods in literature, which has increased the energy efficiencies of vanadium redox flow batteries (VRFBs) by 10 to 20 % depending on their operating current density. However, it is unclear how much electrode overpotential remains after these treatments, which is critical to identifying viable pathways for further improvement. Herein, we demonstrate how membrane-based reference electrodes provide an opportunity to examine individual electrode overpotentials during operation to gain deeper insights into their role in battery performance. Without oxidative treatments, negative electrode overpotential contributions range from 150 to 250 mV depending on the operating current density, overshadowing positive electrode contributions. Use of oxidative treatment reduced negative electrode contributions by nearly 50 % percent from their initial values but marginally increased positive electrode overpotential values. Treating the negative electrode while leaving the positive electrode untreated resulted in the best performance observed but still had 150 to 300 mV of electrode overpotentials remaining, suggesting that additional electrode improvements can still provide significant gains in energy efficiency.

Biphasic layered cathodes represent a strategic advancement in overcoming the inherent limitations of single-phase materials by synergistically integrating distinct phase characteristics. Among these, the P2/O3 biphasic cathode stands out due to its integration of the rapid diffusion kinetics of the P2 phase with the high capacity of the O3 phase, resulting in superior battery performance. Given the critical role of phase ratio in determining the performance of biphasic cathodes, this work systematically examines the influence of synthesis methods, sintering temperatures, and sodium and dopant compositions on phase modulation. A comprehensive analysis of the kinetic and thermodynamic properties of the P2/O3 cathode is conducted, with findings correlated to electrochemical data to elucidate how thermodynamic stability and efficient diffusion kinetics contribute to enhanced functionality. Finally, a brief overview of other biphasic cathodes is provided, comparing their distinctive properties relative to those of the P2/O3 system.