Disclosed herein is a method for selectively reducing, using electrical energy, CO.sub.2 to carbon monoxide or formic acid, a catalyst for use in the method, and an electrochemical reduction system. The method for producing carbon monoxide or formic acid by electrochemically reducing carbon dioxide of the present invention includes (a) reacting carbon dioxide with a metal complex represented by formula (1), and (b) applying a voltage to a reaction product of the carbon dioxide and the metal complex represented by formula (1):

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Non-d.sup.0 rhenium(V) alkylidyne catalysts useful for catalyzing alkyne metathesis reactions, such as homo- and cross-metathesis of alkynes or diynes, ring closing metathesis and ring-opening metathesis, methods or use, and preparation thereof. The catalysts are stable to air and moisture and tolerate a variety of functional groups in substrates.

Materials for binding per- and polyfluoroalkyl substances (PFAS) are disclosed. A fluidic device comprising the materials for detection and quantification of PFAS in a sample is disclosed. The fluidic device may be configured for multiplexed analyses. Also disclosed are methods for sorbing and remediating PFAS in a sample. The sample may be groundwater containing, or suspected of containing, one or more PFAS.

The present disclosure provides methods, compositions, devices, systems and uses that pertain to the electrochemical reduction of CO.sub.2 to CO. The application presents a class of electrodes, incorporating molecular catalysts in nanostructures, for robust and efficient electrochemical systems, specifically, selective and robust hybrid electrodes, by incorporating a rhenium (Re) catalyst into the structure of highly porous heterogeneous materials. These electrodes can be scaled up to desired manufacturing dimensions due to their robust nature and methods of preparation.

This disclosure relates to photocatalytic polyoxometalate compositions of tungstovanadates and uses as water oxidation catalysts. In certain embodiments, the disclosure relates to compositions comprising water, a complex of a tetra-metal oxide cluster and VW.sub.9O.sub.34 ligands, and a photosensitizer. Typically, the metal oxide cluster is Co. In certain embodiments, the disclosure relates to electrodes and other devices comprising water oxidation catalysts disclosed herein and uses in generating fuels and electrical power from solar energy.

Disclosed herein is a method for selectively reducing, using electrical energy, CO.sub.2 to formic acid, a catalyst for use in the method, and an electrochemical reduction system. The method for producing formic acid by electrochemically reducing carbon dioxide of the present invention includes (a) reacting carbon dioxide with a metal complex represented by formula (1), and (b) applying a voltage to a reaction product of the carbon dioxide and the metal complex represented by formula (1):

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A carbon dioxide reducing photocatalyst is provided. The carbon dioxide reducing photocatalyst comprises: an electron receptor comprising a metal oxide; a polymer concentrator deposited on the electron receptor; and a metal catalyst deposited on the electron receptor, wherein electrons move from the polymer concentrator to the metal catalyst through the conduction band of the electron receptor if the polymer concentrator absorbs light.

Non-d.sup.0 rhenium(V) alkylidyne catalysts useful for catalyzing alkyne metathesis reactions, such as homo- and cross-metathesis of alkynes or diynes, ring closing metathesis and ring-opening metathesis, methods or use, and preparation thereof. The catalysts are stable to air and moisture and tolerate a variety of functional groups in substrates.

Materials for binding per- and polyfluoroalkyl substances (PFAS) are disclosed. A fluidic device comprising the materials for detection and quantification of PFAS in a sample is disclosed. The fluidic device may be configured for multiplexed analyses. Also disclosed are methods for sorbing and remediating PFAS in a sample. The sample may be groundwater containing, or suspected of containing, one or more PFAS.

Disclosed herein is a method for selectively reducing, using electrical energy, CO.sub.2 to carbon monoxide, a catalyst for use in the method, and an electrochemical reduction system. The method for producing carbon monoxide by electrochemically reducing carbon dioxide of the present invention includes (a) reacting carbon dioxide with a metal complex represented by formula (1), and (b) applying a voltage to a reaction product of the carbon dioxide and the metal complex represented by formula (1):

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