Systems and methods for electrochemically producing chemical products are provided. In certain cases, the systems and methods described herein are capable of producing chemical products such as hydrogen peroxide in solutions with relatively low concentrations of electrolyte or other dissolved species at high efficiencies and/or low energetic cost. In some cases, redox mediators are used to spatially decouple direct electrochemical processes from the production of the chemical product.

An electrochemical system, an electrochemical stack and a method for carbon dioxide capture and carbon dioxide recovery. The system has a CO.sub.2 capture device where a metal hydroxide base solution reacts with CO.sub.2 to produce carbonates and bicarbonates. The electrochemical stack has one or more electrochemical cells, each with a gas diffusion anode having a hydrogen supply, a cathode spaced from the anode to define an electrolysis region between them for a salt solution, a cation exchange membrane in the electrolysis region next to the cathode and a metal hydroxide region separated from the electrolysis region by the cathode.

A voltage potential between the anode and cathode produces an acid solution in the electrolysis region, conditions the metal hydroxide base solution in the metal hydroxide region and evolves hydrogen at the cathode. A CO.sub.2 evolution device uses the acid and the carbonates and/or bicarbonates to recover CO.sub.2 and to recover the salt solution for reuse in the electrochemical stack.

Methods, apparatuses, and systems related to the electrochemical separation of target gases from gas mixtures are provided. In some cases, a target gas such as carbon dioxide is captured and optionally released using an electrochemical cell (e.g., by bonding to an electroactive species in a reduced state). Some embodiments are particularly useful for selectively capturing the target gas while reacting with little to no oxygen gas that may be present in the gas mixture. Some such embodiments may be useful in applications involving separations from gas mixtures having relatively low concentrations of the target gas, such as direct air capture and ventilated air treatment.

Methods, apparatuses, and systems related to the electrochemical separation of target gases from gas mixtures are provided. In some cases, a target gas such as carbon dioxide is captured and optionally released using an electrochemical cell (e.g., by bonding to an electroactive species in a reduced state). Some embodiments are particularly useful for selectively capturing the target gas while reacting with little to no oxygen gas that may be present in the gas mixture. Some such embodiments may be useful in applications involving separations from gas mixtures having relatively low concentrations of the target gas, such as direct air capture and ventilated air treatment.

A powered toothbrush includes a handle, a power source disposed in the handle, a head including a cavity disposed at a distal end of the handle, an electrically conducting element disposed in the cavity and electrically connected to the power source, and a movable cleaning element connected to the head and movable relative to the cavity. The movable cleaning element includes a tooth cleaning support member, a tooth cleaning element mounted on the support member, and a ferromagnetic member. Application of an electrical current to the electrically conducting element generates a magnetic field at the electrically conducting element. The magnetic field selectively at least one of attracts and repels the ferromagnetic member to move the movable cleaning element relative to the electrically conducting element.

A powered toothbrush includes a handle, a power source disposed in the handle, a head including a cavity disposed at a distal end of the handle, an electrically conducting element disposed in the cavity and electrically connected to the power source, and a movable cleaning element connected to the head and movable relative to the cavity. The movable cleaning element includes a tooth cleaning support member, a tooth cleaning element mounted on the support member, and a ferromagnetic member. Application of an electrical current to the electrically conducting element generates a magnetic field at the electrically conducting element. The magnetic field selectively at least one of attracts and repels the ferromagnetic member to move the movable cleaning element relative to the electrically conducting element.

A fuel oxidation system including an inlet in fluid communication with an interior of a sealed container, and the sealed container is holding permeated gas released from a pressure vessel within the sealed container. Another inlet is in fluid communication with an environment surrounding the sealed container, and the environment includes oxygen gas (O.sub.2). An oxidation module is in fluid communication with the inlet and the other inlet, and the oxidation module is combining the permeated gas received by the inlet with the oxygen gas (O.sub.2) received by the other inlet to form a preferred substance.

A fuel oxidation system including an inlet in fluid communication with an interior of a sealed container, and the sealed container is holding permeated gas released from a pressure vessel within the sealed container. Another inlet is in fluid communication with an environment surrounding the sealed container, and the environment includes oxygen gas (O.sub.2). An oxidation module is in fluid communication with the inlet and the other inlet, and the oxidation module is combining the permeated gas received by the inlet with the oxygen gas (O.sub.2) received by the other inlet to form a preferred substance.

Systems and methods for electrochemical ammonia synthesis comprise electrolytes which have greater efficiency than water, thus leading to cost reductions; and/or cathode catalysts which have lower costs and higher efficiencies in comparison to the iron/nickel catalysts noted above. The electrolyte may be composed primarily of a combination of non-aqueous hydrogen bond donors and acceptors, with high nitrogen solubility and high conductivity. The cathode catalyst may be composed of either a manganese-doped oxide or carbonate material or a two-dimensional carbide or nitride material.

Systems and methods for electrochemical ammonia synthesis comprise electrolytes which have greater efficiency than water, thus leading to cost reductions; and/or cathode catalysts which have lower costs and higher efficiencies in comparison to the iron/nickel catalysts noted above. The electrolyte may be composed primarily of a combination of non-aqueous hydrogen bond donors and acceptors, with high nitrogen solubility and high conductivity. The cathode catalyst may be composed of either a manganese-doped oxide or carbonate material or a two-dimensional carbide or nitride material.