Flowable organic slurry battery with 1000 cycles.

We herein report a newly developed organic slurry flow battery. The strategically designed highly insoluble viologens (C8-V, C12-V, and C18-V) with two electron-activity were utilized to demonstrate a high energy density slurry battery with a stable capacity of 97%, power density of 123 mW cm, and Coulombic efficiency over 99%.

Air-Stable Membrane-Free Magnesium Redox Flow Batteries.

Membrane-free biphasic self-stratified batteries (MBSBs) utilizing aqueous/nonaqueous electrolyte systems have garnered significant attention owing to their flexible manufacturing and cost-effectiveness. In this study, we present an ultrastable high-voltage Mg MBSB based on an aqueous/nonaqueous electrolyte system. The engineered aqueous electrolyte had a wide electrochemical stability window of 3.

Ambient Electroreductive Carboxylation of Unactivated Alkyl Chlorides and Polyvinyl Chloride (PVC) Upgrading.

Electrosynthesis of alkyl carboxylic acids upon activating stronger alkyl chlorides at low-energy cost is desired in producing carbon-rich feedstock. Carbon dioxide (CO), a greenhouse gas, has been recognized as an ideal primary carbon source for those syntheses, and such events also mitigate the atmospheric CO level, which is already alarming. On the other hand, the promising upcycling of polyvinyl chloride to polyacrylate is a high energy-demanding carbon-chloride (C-Cl) bond activation process.

High-Voltage Catholyte for High-Energy-Density Nonaqueous Redox Flow Battery.

Redox flow batteries (RFBs) with high energy densities are essential for efficient and sustainable long-term energy storage on a grid scale. To advance the development of nonaqueous RFBs with high energy densities, a new organic RFB system employing a molecularly engineered tetrathiafulvalene derivative ((PEG3/PerF)-TTF) as a high energy density catholyte was developed. A synergistic approach to the molecular design of tetrathiafulvalene (TTF) was applied, with the incorporation of polyethylene glycol (PEG) chains, which enhance its solubility in organic carbonate electrolytes, and a perfluoro (PerF) group to increase its redox potential.

Electrosynthesis of Verdoheme and Biliverdin Derivatives Following Enzymatic Pathways.

Artificial syntheses of biologically active molecules have been fruitful in many bioinspired catalysis applications. Specifically, verdoheme and biliverdin, bearing polypyrrole frameworks, have inspired catalyst designs to address energy and environmental challenges. Despite remarkable progress in benchtop synthesis of verdoheme and biliverdin derivatives, all reported syntheses, starting from metalloporphyrins or inaccessible biliverdin precursors, require multiple steps to achieve the final desired products.

Molecular Cu Electrocatalyst Escalates Ambient Perfluorooctanoic Acid Degradation.

Groundwater reservoirs contaminated with perfluoroalkyl and polyfluoroalkyl substances (PFASs) need purifying remedies. Perfluorooctanoic acid (PFOA) is the most abundant PFAS in drinking water. Although different degradation strategies for PFOA have been explored, none of them disintegrates the PFOA backbone rapidly under mild conditions.

Main group elements in electrochemical hydrogen evolution and carbon dioxide reduction.

Main-group elements are renowned for their versatile reactivities in organometallic chemistry, including CO insertion and H activation. However, electrocatalysts comprising a main-group element active site have not yet been widely developed for activating CO or producing H. Recently, research has focused on main-group element-based electrocatalysts that are active in redox systems related to fuel-forming reactions.

Development of high-voltage and high-energy membrane-free nonaqueous lithium-based organic redox flow batteries.

Lithium-based nonaqueous redox flow batteries (LRFBs) are alternative systems to conventional aqueous redox flow batteries because of their higher operating voltage and theoretical energy density. However, the use of ion-selective membranes limits the large-scale applicability of LRFBs. Here, we report high-voltage membrane-free LRFBs based on an all-organic biphasic system that uses Li metal anode and 2,4,6-tri-(1-cyclohexyloxy-4-imino-2,2,6,6-tetramethylpiperidine)-1,3,5-triazine (Tri-TEMPO), N-propyl phenothiazine (C3-PTZ), and tris(dialkylamino)cyclopropenium (CP) cathodes.

Electrocatalytic Hydrogen Evolution Using A Molecular Antimony Complex under Aqueous Conditions: An Experimental and Computational Study on Main-Group Element Catalysis.

Electrocatalytic hydrogen gas production is considered a potential pathway towards carbon-neutral energy sources. However, the development of this technology is hindered by the lack of efficient, cost-effective, and environmentally benign catalysts. In this study, a main-group-element-based electrocatalyst, SbSalen, is reported to catalyze the hydrogen evolution reaction (HER) in an aqueous medium.

Outer-coordination sphere in multi-H/multi-emolecular electrocatalysis.

Electrocatalysis is an indispensable technique for small-molecule transformations, which are essential for the sustainability of society. Electrocatalysis utilizes electricity as an energy source for chemical reactions. Hydrogen is considered the "fuel for the future," and designing electrocatalysts for hydrogen production has thus become critical.

Electrocatalytic Dechlorination of Dichloromethane in Water Using a Heterogenized Molecular Copper Complex.

The remediation of organohalides from water is a challenging process in environment protection and water treatment. Herein, we report a molecular copper(I) complex with two triazole units, , in a heterogeneous aqueous system that is capable of dechlorinating dichloromethane (CHCl) to afford hydrocarbons (methane, ethane, and ethylene). The catalytic performance is evaluated in water and presented high Faradaic efficiency (average 70% CH) across a range of potentials (-1.

Effects of Appended Poly(ethylene glycol) on Electrochemical CO Reduction by an Iron Porphyrin Complex.

Electrochemical carbon dioxide (CO) reduction is a sustainable approach for transforming atmospheric CO into chemical feedstocks and fuels. To overcome the kinetic barriers of electrocatalytic CO reduction, catalysts with high selectivity, activity, and stability are needed. Here, we report an iron porphyrin complex, , with a poly(ethylene glycol) unit in the second coordination sphere, as a highly selective and active electrocatalyst for the electrochemical reduction of CO to carbon monoxide (CO).

Hydrodechlorination of Dichloromethane by a Metal-Free Triazole-Porphyrin Electrocatalyst: Demonstration of Main-Group Element Electrocatalysis*.

In this work, the electrocatalytic reduction of dichloromethane (CH Cl ) into hydrocarbons involving a main group element-based molecular triazole-porphyrin electrocatalyst H2PorT8 is reported. This catalyst converted CH Cl in acetonitrile to various hydrocarbons (methane, ethane, and ethylene) with a Faradaic efficiency of 70 % and current density of -13 mA cm at a potential of -2.2 V vs.

Surprisingly big linker-dependence of activity and selectivity in CO reduction by an iridium(i) pincer complex.

Here, we report the quantitative electroreduction of CO2 to CO by a PNP-pincer iridium(i) complex bearing amino linkers in DMF/water. The electrocatalytic properties greatly depend on the choice of linker within the ligand. The complex 3-N is far superior to the analogues with methylene and oxygen linkers, showing higher activity and better selectivity for CO2 over proton reduction.

Enhanced Electrocatalytic Activity of a Zinc Porphyrin for CO Reduction: Cooperative Effects of Triazole Units in the Second Coordination Sphere.

The control of the second coordination sphere in a coordination complex plays an important role in improving catalytic efficiency. Herein, we report a zinc porphyrin complex ZnPor8T with multiple flexible triazole units comprising the second coordination sphere, as an electrocatalyst for the highly selective electrochemical reduction of carbon dioxide (CO ) to carbon monoxide (CO). This electrocatalyst converted CO to CO with a Faradaic efficiency of 99 % and a current density of -6.

A pH-Neutral, Aqueous Redox Flow Battery with a 3600-Cycle Lifetime: Micellization-Enabled High Stability and Crossover Suppression.

Redox-flow batteries (RFBs) are a highly promising large-scale energy storage technology for mitigating the intermittent nature of renewable energy sources. Here, the design and implementation of a micellization strategy in an anthraquinone-based, pH-neutral, nontoxic, and metal-free aqueous RFB is reported. The micellization strategy (1) improves stability by protecting the redox-active anthraquinone core with a hydrophilic poly(ethylene glycol) shell and (2) increases the overall size to mitigate the crossover issue through a physical blocking mechanism.

Enhanced Molecular CO Electroreduction Enabled by a Flexible Hydrophilic Channel for Relay Proton Shuttling.

The effects of primary and second coordination spheres on molecular electrocatalysis have been extensively studied, yet investigations of third functional spheres are rarely reported. Here, an electrocatalyst (ZnPEG8T) was developed with a hydrophilic channel as a third functional sphere that facilitates relay proton shuttling to the primary and second coordination spheres for enhanced catalytic CO reduction. Using foot-of-the-wave analysis, the ZnPEG8T catalyst displayed CO -to-CO activity (TOF ) thirty times greater than that of the benchmark catalyst without a third functional sphere.

PEGylation-Enabled Extended Cyclability of a Non-aqueous Redox Flow Battery.

Non-aqueous redox flow batteries (RFBs) are promising energy storage devices owing to the broad electrochemical window of organic solvents. Nonetheless, the wide application of these batteries has been limited by the low stability and limited solubility of organic materials, as well as the insufficient ion conductivity of the cell separators in non-aqueous electrolytes. In this study, two viologen analogues with poly(ethylene glycol) (PEG) tails are designed as anolytes for non-aqueous RFBs.