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Despite many recent efforts, the field of organic electrosyn‐thesis faces important challenges due to the intricate nature of heterogeneous redox processes, the wide parameter space to be explored and the lack of standardized methods. To overcome these limitations, we developed a cost‐effective high‐throughput electrochemical (HTE) reactor capable of running 24 individually controlled parallel reactions. This system allows the rapid testing of electrochemical parameters on a given reaction, assessing not only yield but also reproducibility. Using the hypervalent iodine‐mediated dearomatization of phloretic acid as a demonstration of HTE capabilities, we ran more than 200 electrosyntheses in different experimental conditions and demonstrate the effect of parameters such as total charge transferred, current, electrode materials, electrolyte formulation and concentration, mediator formulation and concentration and electrochemical technique of oxidation. Notably, this report demonstrates that while catalytic amounts of iodine mediator can be used successfully, the reproducibility may be affected, which calls for a cautious approach when developing similar transformations. Using cyclic voltammetry, density functional theory, chronopotentiometry, and Raman spectroscopy, we shed light on the causes of this issue. [ABSTRACT FROM AUTHOR]

The electrification of the transport sector has created an increasing demand for lithium‐ion batteries that can provide high power intermittently while maintaining a high energy density. Given the difficulty in designing a single redox material with both high power and energy density, electrodes based on composites of several electroactive materials optimized for power or capacity are being studied extensively. Among others, fast‐charging LiFePO4 and high energy Li(NixMnyCoz)O2 are commonly employed in industrial cell manufacturing. This study focuses on comparing different approaches to combining these two active materials into a single electrode. These arrangements were compared using standard electrochemical (dis)charge procedures and using synchrotron X‐ray fluorescence to identify variations in solution concentration gradient formation. The electrochemical performance of the layered electrodes with the high‐power material on top is found to be enhanced relative to its blended electrode counterpart when (dis)charged at the same specific currents. These findings highlight dual‐layer lithium‐ion batteries as an inexpensive way of increasing energy and power density of lithium‐ion batteries as well as a model system to study and exploit the synergistic effects of blended electrodes. [ABSTRACT FROM AUTHOR]

The front cover of the journal ChemElectroChem showcases the potential of high-throughput electrosynthesis, with a researcher collecting the products with the highest yield. This method offers the opportunity to accelerate research by optimizing existing reactions and discovering new pathways. The cover is associated with a research article by Eric McCalla, Janine Mauzeroll, and their colleagues, which provides more information on this topic. [Extracted from the article]

Developing metallic nanocatalysts with high reaction activity, selectivity and practical durability is a promising and active subfield in electrocatalysis. In the classical "bottom‐up" approach to synthesize stable nanomaterials by chemical reduction, stabilizing additives such as polymers or organic surfactants must be present to cap the nanoparticle to prevent material bulk aggregation. In recent years, biological systems have emerged as green alternatives to support the uncoated inorganic components. One key advantage of biological templates is their inherent ability to produce nanostructures with controllable composition, facet, size and morphology under ecologically friendly synthetic conditions, which are difficult to achieve with traditional inorganic synthesis. In addition, through genetic engineering or bioconjugation, bio‐templates can provide numerous possibilities for surface functionalization to incorporate specific binding sites for the target metals. Therefore, in bio‐templated systems, the electrocatalytic performance of the formed nanocatalyst can be tuned by precisely controlling the material surface chemistry. With controlled improvements in size, morphology, facet exposure, surface area and electron conductivity, bio‐inspired nanomaterials often exhibit enhanced catalytic activity towards electrode reactions. In this Review, recent research developments are presented in bio‐approaches for metallic nanomaterial synthesis and their applications in electrocatalysis for sustainable energy storage and conversion systems. [ABSTRACT FROM AUTHOR]

We are reporting the application of scanning electrochemical cell microscopy to probe and identify nanometric defects in a multilayered aryl film formed by aryldiazonium reduction. We have determined by numerical simulation that, due to pipette geometry restrictions, the best sensitivity towards pinhole size can be obtained when measuring small pinholes (≤10 nm) with moderately large pipette sizes (ca. 500 nm). [ABSTRACT FROM AUTHOR]

Keywords: electrode architecture; power density; fast charge; blended electrode; X-ray fluorescence EN electrode architecture power density fast charge blended electrode X-ray fluorescence 1 1 1 11/07/23 20231102 NES 231102 B The Front Cover b shows Li-metal cells which contain two active materials (red and blue). Front Cover: Exploring the Synergistic Effects of Dual-Layer Electrodes for High Power Li-Ion Batteries (ChemElectroChem 21/2023) Electrode architecture, power density, fast charge, blended electrode, X-ray fluorescence. [Extracted from the article]

An approach to electrogenerated chemiluminescence (ECL) signal enhancement, utilizing the highly tailorable ring‐opening metathesis polymerization (ROMP) to generate novel ECL active nanoscale structures is explored. The strategy involves integrating into a single polymer multiple copies of an analogue of the established ECL luminophore, tris(2,2'‐bipyridine)ruthenium(II) (Ru(bpy)32+). Through the addition of hydrophobic and hydrophilic functional groups to the polymer architecture, these ECL active block copolymers are engineered to self‐assemble when exposed to aqueous environments. Self‐assembled ruthenium nanospheres generated through this methodology were found to demonstrate drastic signal amplification properties compared to their non‐assembled polymer counterparts. Characterization methodologies conducted throughout the bottom‐up synthesis of the nanospheres, utilizing the ECL reference of Ru(bpy)32+, facilitated investigating the origins of the nanosphere's signal enhancement. [ABSTRACT FROM AUTHOR]

The ionic liquid 1‐ethyl‐3‐methylimidazolium bis(trifluoromethylsulfonyl)imide was used in the scanning micropipette contact method to extend the electrochemical window of the electrolyte solution and enable the study of lithium‐ion battery materials with higher oxidation potential. Localized electrochemical measurements were performed on lithium iron phosphate particles that were drop‐cast onto a glassy carbon substrate. Investigation of the active materials occurred on a small scale (ca. 10 μm diameter), defined by the area of meniscus contact between the electrolyte solution in the micropipette and the substrate. Our studies showed that the SMCM probe is stable and can be used to analyze high energy lithium‐ion battery materials in the range of 2.5 to 5.1 V vs. Li/Li+. Extended potential, higher efficiency: Scanning micropipette contact method (SMCM) is extended to ionic liquid studies. The potential window for 1‐ethyl‐3‐methylimidazolium bis(trifluoromethylsulfonyl)imide (EMI TFSI) ionic liquid is suitable to examine high‐energy lithium‐ion battery materials. The electrochemical properties of lithium iron phosphate (LFP) particles drop‐cast onto a glassy carbon substrate are probed under inert atmosphere. SMCM‐coulombic efficiency of LFP particles in EMI TFSI is estimated to be higher than 90 %. [ABSTRACT FROM AUTHOR]

Abstract: The chemical modification of an sp2 hybridized carbon surface in a controllable manner is very challenging but also crucial for many applications. An inverse electron demand Diels–Alder (IEDDA) reaction using microcontact printing technique is introduced to spatially control the modification of a highly ordered pyrolytic graphite (HOPG) surface under ambient conditions. The covalent modification was characterized by Raman spectroscopy, XPS, and SECM. Tetrazine derivatives can effectively react with an HOPG surface and with microcontact printing methods resulting in spatially patterned surfaces being produced with micrometer‐scale resolution. [ABSTRACT FROM AUTHOR]

Herein, we validate a novel cuvette-based approach to measure electrogenerated chemiluminescence (ECL) by employing the hyphenation of a commercial spectrometer and a potentiostat. The new experimental design provides simultaneous acquisition of electrochemical and ECL data, allowing complementary analysis by both techniques. Preliminary analysis of an organometallic ECL standard, tris(2,2′-bipyridine)ruthenium(II) (Ru(bpy)32+), and tripropylamine (TPA), showed excellent reproducibility both in terms of the electrochemistry and the ECL signal. Equally as important, the acquired electrochemistry and ECL from the Ru(bpy)32+/TPA system served as a baseline for evaluating the ECL response of polymerizable ruthenium luminophores. [ABSTRACT FROM AUTHOR]

d-Serine acts as an endogenous co-agonist for N-methyl- d-aspartate receptors at synapses, making it essential for proper brain development and function. This amino acid has also been linked to several neurodegenerative diseases such as Alzheimer's disease and dementia. Nevertheless, the primary site and mechanism of d-serine release remains unclear. We recently demonstrated the use of an enzymatic amperometric biosensor for the in vivo quantification of endogenous d-serine release in Xenopus laevis tadpoles. Herein, we investigate the effect of the permselective poly( meta-phenylenediamine) electropolymerization conditions on the biosensor's response time and selectivity. Scanning electrochemical microscopy (SECM) is then used with the optimized biosensor to measure localized release of d-serine from a model system. This SECM methodology, which provides high spatial and temporal resolution, could be useful to investigate the primary site and mechanism of d-serine release in other biological samples. [ABSTRACT FROM AUTHOR]

State-of-the-art scanning probe microscopy (SPM) methods as applied to energy conversion and storage devices, specifically lithium-ion batteries, are reviewed with an emphasis on the electroactive elements. The unique ability of SPM-based methods to provide localized information has proven highly valuable for the in-depth understanding of the fundamental mechanisms, processes, and degradation of lithium-ion batteries (LIBs). As such, SPM analysis is poised to play a strong role in the competition for new higher performing LIBs, especially given the unprecedented choice and availability of SPM techniques tailored to provide physical and chemical information at the nanoscale. [ABSTRACT FROM AUTHOR]

Mussel byssus offers bio‐inspired designs for advanced adhesives, coatings, and supramolecular hydrogels. Solidification of secreted proteins into mechanically robust fibers is triggered by a pH jump from acidic fluid condensates to basic seawater conditions driving protein crosslinking by metal coordination with 3,4‐dihydroxyphenylalanine (DOPA). Knowledge of the dynamic and localized pH changes during secretion is currently lacking. Yet, this information is crucial for controlling the gelation and properties of mussel‐inspired DOPA‐modified materials. Here, an iridium oxide‐based pH microsensor combining high mechanical stability and spatial resolution is used to measure the acidic pH during byssus secretion and to map mussel‐inspired hydrogels revealing compositional heterogeneity resulting in mechanically distinct regions. Within the hydrogel, high pH values >12 are measured which are detrimental to DOPA due to its strong propensity for oxidation, which adversely alters gel properties. This demonstrates the need to improve preparation methods of mussel‐inspired adhesive materials to more closely mimic native processes. [ABSTRACT FROM AUTHOR]

Cover Feature: Recent Advances in Bio-Templated Metallic Nanomaterial Synthesis and Electrocatalytic Applications (ChemSusChem 3/2021) Keywords: biological templates; electrocatalysis; energy conversion/storage; nanomaterials; surface functionalization EN biological templates electrocatalysis energy conversion/storage nanomaterials surface functionalization 756 756 1 02/17/21 20210205 NES 210205 B The Cover Feature b (designed by Dr. Nicholas A. Payne, University of Western Ontario) shows the different components required for applying bio-templated metallic nanomaterials in electrocatalysis. Biological templates, electrocatalysis, energy conversion/storage, nanomaterials, surface functionalization. [Extracted from the article]

The Back Cover picture represents a paper in which scanning probe microscopy methods applied to energy conversion and storage devices (specifically lithium‐ion batteries) are reviewed, with an emphasis on the electroactive elements. More information can be found in the Review by S. B. Schougaard, J. Mauzeroll, and co‐workers on page 6 in Issue 1, 2017 (DOI: 10.1002/celc.201600571). [ABSTRACT FROM AUTHOR]