A clad porous metal substrate for use in a metal-supported electrochemical cell, wherein a metal support layer of defined porosity is clad on top and bottom sides with a layer containing a metal and/or a metal oxide. A metal-supported electrochemical half-cell and a metal-supported electrochemical cell are also described.

An electrolysis system includes at least one H.sub.2O electrolysis apparatus that electrolyzes water to produce hydrogen; and at least one CO.sub.2 electrolysis apparatus that electrolyzes carbon dioxide to produce carbon monoxide. The electrolysis system includes a co-electrolysis apparatus that co-electrolyzes water and carbon dioxide to produce less hydrogen per unit time than produced by the at least one H.sub.2O electrolysis apparatus and less carbon monoxide per unit time than produced by the at least one CO.sub.2 electrolysis apparatus.

Solid oxide electrolytic cell assembly (SOEC) and methods for making SOECs are provided. An exemplary method includes forming a functionalized zeolite templated carbon (ZTC). The functionalized ZTC is formed by forming a CaX zeolite, depositing carbon in the CaX zeolite using a chemical vapor deposition (CVD) process to form a carbon/zeolite composite, treating the carbon/zeolite composite with a solution including hydrofluoric acid to form a ZTC, and treating the ZTC to add catalyst sites. In the method, the functionalized ZTC is incorporated into electrodes by forming a mixture of the functionalized ZTC with a calcined solid oxide electrolyte, and calcining the mixture. The method includes forming an electrode assembly, forming the SO electrolytic cell assembly, and coupling the SO electrolytic cell assembly to a heat source.

Herein discussed is an electrochemical reactor comprising a mixed-conducting membrane, wherein the membrane comprises an electronically conducting phase and an ionically conducting phase, wherein the reactor is capable of reforming a hydrocarbon electrochemically, wherein the electrochemical reforming reactions involve the exchange of an ion through the membrane to oxidize the hydrocarbon. Further discussed herein is a method of producing hydrogen comprising providing an electrochemical (EC) reactor having a mixed-conducting membrane, introducing a first stream comprising a hydrocarbon to the reactor, introducing a second stream comprising water to the reactor, and reducing the water in the second stream to produce hydrogen, wherein the first stream and the second stream do not come in contact with each other in the reactor, and wherein the hydrocarbon is reformed electrochemically in the EC reactor.

Herein discussed is an electrochemical reactor comprising a mixed-conducting membrane, wherein the membrane comprises an electronically conducting phase and an ionically conducting phase, wherein the reactor is capable of reforming a hydrocarbon electrochemically, wherein the electrochemical reforming reactions involve the exchange of an ion through the membrane to oxidize the hydrocarbon. Further discussed herein is a method of producing hydrogen comprising providing an electrochemical (EC) reactor having a mixed-conducting membrane, introducing a first stream comprising a hydrocarbon to the reactor, introducing a second stream comprising water to the reactor, and reducing the water in the second stream to produce hydrogen, wherein the first stream and the second stream do not come in contact with each other in the reactor, and wherein the hydrocarbon is reformed electrochemically in the EC reactor.

Herein discussed is a hydrogen production system comprising a first reactor zone and a second reactor zone, wherein both reactor zones comprise an ionically conducting membrane, wherein the first zone is capable of reforming a hydrocarbon electrochemically and the second zone is capable of performing water gas shift reactions electrochemically, wherein the electrochemical reforming reactions involve the exchange of an ion through the membrane to oxidize the hydrocarbon and wherein electrochemical water gas shift reactions involve the exchange of an ion through the membrane and include forward water gas shift reactions, or reverse water gas shift reactions, or both. In an embodiment, the membrane is mixed conducting. In an embodiment, the membrane comprises an electronically conducting phase and an ionically conducting phase.

Herein discussed is a method of producing hydrogen comprising introducing a first stream comprising a fuel to an electrochemical (EC) reactor having a mixed-conducting membrane, introducing a second stream comprising water to the reactor, reducing the water in the second stream to produce hydrogen, and recycling at least portion of the produced hydrogen to the first stream, wherein the membrane comprises an electronically conducting phase and an ionically conducting phase; and wherein the first stream and the second stream do not come in contact with each other in the reactor.

A proton conductor contains a metal oxide that has a perovskite structure and that is represented by formula (1): A.sub.xB.sub.1-yM.sub.yO.sub.3-δ, where an element A is at least one element selected from the group consisting of Ba, Ca, and Sr, an element B is at least one element selected from the group consisting of Ce and Zr, an element M is at least one element selected from the group consisting of Y, Yb, Er, Ho, Tm, Gd, In, and Sc, δ indicates an oxygen deficiency amount, and 0.95≤x≤1 and 0<y≤0.5 are satisfied.

Herein discussed is a method of producing hydrogen or carbon monoxide comprising introducing a waste gas having a total combustible species (TCS) content of no greater than 60 vol % into an electrochemical (EC) reactor, wherein the EC reactor comprises a mixed-conducting membrane, wherein the membrane comprises an electronically conducting phase and an ionically conducting phase. Also disclosed herein is an integrated hydrogen production system comprising a waste gas source and an electrochemical (EC) reactor comprising a mixed-conducting membrane, wherein the membrane comprises an electronically conducting phase and an ionically conducting phase, wherein the waste gas source is configured to send its exhaust to the EC reactor, wherein the exhaust has a total combustible species (TCS) content of no greater than 60 vol %.

In a first implementation, a method for exfoliation of graphene flakes from a graphite sample includes compressing a graphite sample in an electrochemical reactor and applying a voltage between the graphite sample and an electrode in the electrochemical cell.