This invention relates to apparatuses, systems and methods for the production and separation of gases in membraneless liquid alkaline electrolysis, and particularly to electrodes and electrode assemblies for use in a divergent electrolytic flow-through apparatus. The apparatus according to the invention comprises an inlet chamber; first and second permeable electrodes each having first and second sides and defining an inner aperture surrounding the inner region, the first sides of the first and second electrodes arranged to face each other to define an electrode gap within the inlet chamber; a first electrolytic solution inlet into the outer region and a second electrolytic solution inlet into the inner region; a first outlet in fluid flow communication with the second side of the first electrode, and a second outlet in fluid flow communication with the second side of the second electrode.

This invention relates to apparatuses, systems and methods for the production and separation of gases in membraneless liquid alkaline electrolysis, and particularly to electrodes and electrode assemblies for use in a divergent electrolytic flow-through apparatus. The apparatus according to the invention comprises an inlet chamber; first and second permeable electrodes each having first and second sides and defining an inner aperture surrounding the inner region, the first sides of the first and second electrodes arranged to face each other to define an electrode gap within the inlet chamber; a first electrolytic solution inlet into the outer region and a second electrolytic solution inlet into the inner region; a first outlet in fluid flow communication with the second side of the first electrode, and a second outlet in fluid flow communication with the second side of the second electrode.

The present invention discloses a membrane-less reactor design for microbial electrosynthesis of alcohols from carbon dioxide (CO.sub.2). The membrane-less reactor design thus facilitates higher and efficient CO.sub.2 transformation to alcohols via single pot microbial electrosynthesis. The reactor design operates efficiently avoiding oxygen contact at working electrode without using membrane, in turn there is an increase in CO.sub.2 solubility and its bioavailability for subsequent CO.sub.2 conversion to alcohols at faster rate. The present invention further provides a process of operation of the reactor for biotransformation of the carbon dioxide.

The present invention discloses a membrane-less reactor design for microbial electrosynthesis of alcohols from carbon dioxide (CO.sub.2). The membrane-less reactor design thus facilitates higher and efficient CO.sub.2 transformation to alcohols via single pot microbial electrosynthesis. The reactor design operates efficiently avoiding oxygen contact at working electrode without using membrane, in turn there is an increase in CO.sub.2 solubility and its bioavailability for subsequent CO.sub.2 conversion to alcohols at faster rate. The present invention further provides a process of operation of the reactor for biotransformation of the carbon dioxide.

An electrocatalyst comprising molybdenum disulfide nanosheets with dispersed iron phosphide nanoparticles is described. The molybdenum disulfide nanosheets may have an average length in a range of 300 nm-1 μm and the iron phosphide nanoparticles may have an average diameter in a range of 5-20 nm. The electrocatalyst may have an electroactive surface area in a range of 10-50 mF.Math.cm.sup.−2 when deposited on a working electrode for use in a hydrogen evolution reaction.

A method of manufacturing an electrode by disposing a three-dimensional substrate in a metal nitrate solution, drying, and thermally phosphatizing with a phosphorus source under inert gas to form a metal based phosphate catalyst on the substrate. An electrocatalyst and electrode produced via the method are also provided.

Bacteria-based catalysts including a bacterium and one or more metal oxides are disclosed. The metal oxides are dispersed on the surface of the bacterium. The bacterium can be an electrogenic bacterium, which employs an extracellular electron transport pathway to transfer metabolically generated electrons to cell-exterior. The bacteria-based catalysts can be made by: (a) oxidizing a substrate molecule by a bacterium to generate electrons; (b) transporting the electrons to one or more metal oxide precursors; and (c) reducing the metal oxide precursors to metal oxides. The bacteria-based catalysts disclosed herein can be used in electrocatalysis, photocatalysis, or chemical catalysis. For example, they can catalyze oxygen evolution reaction (OER) and outperform commercial metal oxide catalyst for OER with superior operational stability.

Bacteria-based catalysts including a bacterium and one or more metal oxides are disclosed. The metal oxides are dispersed on the surface of the bacterium. The bacterium can be an electrogenic bacterium, which employs an extracellular electron transport pathway to transfer metabolically generated electrons to cell-exterior. The bacteria-based catalysts can be made by: (a) oxidizing a substrate molecule by a bacterium to generate electrons; (b) transporting the electrons to one or more metal oxide precursors; and (c) reducing the metal oxide precursors to metal oxides. The bacteria-based catalysts disclosed herein can be used in electrocatalysis, photocatalysis, or chemical catalysis. For example, they can catalyze oxygen evolution reaction (OER) and outperform commercial metal oxide catalyst for OER with superior operational stability.

A CoVO.sub.x composite electrode and method of making is described. The composite electrode comprises a substrate with an average 0.5-5 m thick layer of CoVO.sub.x having pores with average diameters of 2-200 nm. The method of making the composite electrode involves contacting the substrate with an aerosol comprising a solvent, a cobalt complex, and a vanadium complex. The CoVO.sub.x composite electrode is capable of being used in an electrochemical cell for water oxidation.

Methods and systems for hydrogen production or production of a reduced target molecule are described, wherein a nicotinamide co-factor dependent membrane hydrogenase or a nicotinamide co-factor dependent membrane enzyme presented on a nanolipoprotein adsorbed onto an electrically conductive supporting structure, which can preferably be chemically inert, is contacted with protons or a target molecule to be reduced and nicotinamide cofactors in presence of an electric current and one or more electrically driven redox mediators. Methods and systems for production of hydrogen or a reduced target molecule are also described wherein a membrane-bound hydrogenase enzyme or enzyme capable or reducing a target molecule is contacted with protons or the target molecule, a nicotinamide co-factor and a nicotinamide co-factor dependent membrane hydrogenase presented on a nanolipoprotein particle for a time and under condition to allow hydrogen production or production of a reduced target molecule in presence of an electrical current and of an electrically driven redox mediator.