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Bipolar electrochemistry (BE) combined with electrochemiluminescence (ECL) has gained considerable attention as a versatile and powerful analytical technique operating in a wireless manner. However, only co‐reactant ECL has been reported so far when using a BE setup. In this work, the generation of annihilation ECL at the anodic extremity of a bipolar electrode (BPE) is demonstrated in two different spatial arrangements of the electrodes. The reported approach is based on a synergetic effect between the asymmetric electroactivity induced across the BPE, which produces different redox states of [Ru(bpy)3]2+, and the electro‐migration mechanism of the formed ionic species, allowing the localization and concentration of the ECL emission. The presented approach demonstrating annihilation ECL via BE, paves the way for the design of easy and straightforward light‐emitting platforms for multiple applications. [ABSTRACT FROM AUTHOR]

An electromagnet is a particular device that takes advantage of electrical currents to produce concentrated magnetic fields. The most well‐known example is a conventional solenoid, having the form of an elongated coil and creating a strong magnetic field through its center when it is connected to a current source. Spontaneous redox reactions located at opposite ends of an anisotropic Janus swimmer can effectively mimic a standard power source, due to their ability to wirelessly generate a local electric current. Herein, we propose the coupling of thermodynamically spontaneous redox reactions occurring at the extremities of a hybrid Mg/Pt Janus swimmer with a solenoidal geometry to generate significant magnetic fields. These chemically driven electromagnets spontaneously transform the redox‐induced electric current into a magnetic field with a strength in the range of μT upon contact with an acidic medium. Such on‐board magnetization allows them to perform compass‐like rotational motion and magnetotactic displacement in the presence of external magnetic field gradients, without the need of using ferromagnetic materials for the swimmer design. The torque force experienced by the swimmer is proportional to the internal redox current, and by varying the composition of the solution, it is possible to fine‐tune its angular velocity. [ABSTRACT FROM AUTHOR]

Organic mixed ionic‐electronic conductors (OMIEC) have emerged as pivotal materials in organic bioelectronics, particularly when integrated into organic electrochemical transistors (OECTs). Conducting polymer‐based devices have indeed demonstrated their capability to transduce biological signals into amplified output signals, harnessing the high transconductance of OECTs. The OECT operating principle and sensing capability strongly depend on ion‐conjugated backbone coupling: the dual nature of OMIECs, i.e. ion‐conductor and electron/hole‐conductor, presents an intrinsic interface in the bulk of the thin film across which transduction of ionic signals into electronic signals and vice versa occurs. Recent works have shown how selective sodium and potassium detection can be achieved by direct chemical modification of the polymer. Such modifications introduce ligands with affinity for the cations of interest as substituents on the polymer chain. The present work explores the integration of specifically modified conducting polymers into OECT channels, offering selectivity for zinc cations. Zinc fluxes are crucial in various biological processes, and their reliable detection, especially at low concentrations, is an important challenge. By electropolymerizing a thiophene‐based trimer, modified with a dipicolylamine (DPA) substituent, a conducting polymer‐based OECT is obtained that can selectively detect Zn2+ in the 10−6 to 10−3 mol L−1 concentration range in physiological buffers. [ABSTRACT FROM AUTHOR]

Water splitting has become a sustainable and clean alternative for hydrogen production. Commonly, the efficiency of such reactions is intimately related to the physico‐chemical properties of the catalysts that constitute the electrolyzer. Thus, the development of simple and fast methods to evaluate the electrocatalytic efficiency of an electrolyzer is highly required. In this work, we present an unconventional method based on the combination of bipolar electrochemistry and light‐emitting diodes, which allows the evaluation of the electrocatalytic performance of the two types of catalysts, composing an electrolyzer, namely for oxygen and hydrogen evolution reactions, respectively. The integrated light emission of the diode acts as an optical readout of the electrocatalytic information, which simultaneously depends on the composition of the anode and the cathode. The electrocatalytic activity of Au, Pt, and Ni electrodes, connected to the LED in multiple anode/cathode configurations, towards the water splitting reactions has been evaluated. The efficiency of the electrolyzer can be represented in terms of the onset electric field (ϵonset) for light emission, obtaining variations that are in agreement with data reported with conventional electrochemistry. This work introduces a straightforward method for evaluating electrocatalysts and underscores the importance of material characterization in developing efficient electrolyzers for hydrogen production. [ABSTRACT FROM AUTHOR]

Additive manufacturing with concrete – guidance for planning and implementation of projects This guideline, created by the DAfStb Working Group "Digital Concrete Construction through Additive Manufacturing," serves as a comprehensive resource to support the planning and implementation of additive manufacturing projects in concrete construction. It is intended for architects, planners, applicants, material manufacturers, construction companies, and other parties involved in construction. After a brief introduction to the classification, terminology, and methods of additive manufacturing, legal aspects and approval procedures are highlighted to ensure seamless integration of this technology into construction practice. The guide addresses the integration of additive manufacturing methods with concrete into construction law, explains the approval process, and offers assistance for coordinating responsibilities in projects. It addresses technical rules for the design and construction of structures, particularly for walls produced by additive manufacturing, and covers constructive aspects of reinforcement. An important component is concrete and component testing, including methods for sample preparation and testing procedures for fresh and hardened concrete, making the guide a useful tool for professionals in the field of digital concrete construction. [ABSTRACT FROM AUTHOR]

Electromagnetically induced rotation is a key process of many technological systems that are used in daily life, especially for energy conversion. In this context, the Lorentz force‐induced deviation of charges is a crucial physical phenomenon to generate rotation. Herein, they combine the latter with the concept of bipolar electrochemistry to design a wireless magnetoelectrochemical rotor. Such a device can be considered as a wet analog of a conventional electric motor. The main driving force that propels this actuator is the result of the synergy between the charge‐compensating ion flux along a bipolar electrode and an external magnetic field applied orthogonally to the surface of the object. The trajectory of the wirelessly polarized rotor can be controlled by the orientation of the magnetic field relative to the direction of the global electric field, producing a predictable clockwise or anticlockwise motion. Fine‐tuning of the applied electric field allows for addressing conducting objects having variable characteristic lengths. [ABSTRACT FROM AUTHOR]

Cable bacteria are multicellular, filamentous bacteria that use internal conductive fibers to transfer electrons over centimeter distances from donors within anoxic sediment layers to oxygen at the surface. We extracted the fibers and used them as free‐standing bio‐based electrodes to investigate their electrocatalytic behavior. The fibers catalyzed the reversible interconversion of oxygen and water, and an electric current was running through the fibers even when the potential difference was generated solely by a gradient of oxygen concentration. Oxygen reduction as well as oxygen evolution were confirmed by optical measurements. Within living cable bacteria, oxygen reduction by direct electrocatalysis on the fibers and not by membrane‐bound proteins readily explains exceptionally high cell‐specific oxygen consumption rates observed in the oxic zone, while electrocatalytic water oxidation may provide oxygen to cells in the anoxic zone. [ABSTRACT FROM AUTHOR]

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Conducting polymers find applications as active materials in electrochromic devices thanks to their tunable optoelectronic and electrochemical properties. Such versatility can be further enhanced by copolymerizing various aromatic monomers in order to produce new materials. In this work, we present different copolymers obtained by electropolymerization of an N‐substituted dithienylpyrrole (SNSBA) with either 3,4‐ethylendioxythiophene (EDOT) or bithiophene (BTh). The electrochemical, spectroscopic, and electrical properties were characterized across their different neutral and charged states by means of ex‐situ and in‐situ spectroelectrochemical techniques. The peculiar feature of SNSBA lies in the aniline bearing substituent of the central pyrrole unit that allows polymerization to occur at three different sites, yielding a cross‐linked polymer network. Our findings show that the SNSBA comonomer not only influences the optoelectronic properties of the final materials with respect to their homopolymers, but also induces a lowering of the hysteresis of the insulating/conducting transition (ΔEG<280 mV), likely due to the cross‐linked nature of the polymer layer. These features are promising to develop a new class of copolymers for electrochromic devices with stable, reversible, and fast operation. [ABSTRACT FROM AUTHOR]