A titanium sub-oxide/ruthenium oxide composite electrode and a preparation method and application thereof. Titanium-based titanium sub-oxide nanotubes is taken as a bottom layer, and titanium sub-oxide doped ruthenium oxide is taken as a surface composite active layer. A titanium substrate is anodized in a fluorine-containing ionic electrolyte, taken out, subjected to heating and roasting, cooled and then subjected to cathodic electrochemical reduction in polarizing liquid, so that a titanium-based titanium sub-oxide nanotube electrode is obtained; and then the titanium-based titanium sub-oxide nanotube electrode is taken as a cathode to be electrodeposited in a ruthenium trichloride electrolyte doped with titanium sub-oxide powder, taken out and then subjected to heating and roasting, so that the titanium sub-oxide/ruthenium oxide composite electrode is obtained.

The present invention relates to the production of graphene from CO.sub.2 through electrolysis and exfoliation processes. One embodiment is a method for producing graphene comprising (i) performing electrolysis between an electrolysis anode and an electrolysis cathode in a molten carbonate electrolyte to generate carbon nanomaterial on the cathode, and (ii) electrochemically exfoliating the carbon nanomaterial from a second anode to produce graphene. The exfoliating step produces graphene in high yield than thicker, conventional graphite exfoliation reactions. CO.sub.2 can be the sole reactant used to produce the valuable product as graphene. This can incentivize utilization of CO.sub.2, and unlike alternative products made from CO.sub.2 such as carbon monoxide or other fuels such as methane, use of the graphene product does not release this greenhouse gas back into the atmosphere.

The present invention relates to the production of graphene from CO.sub.2 through electrolysis and exfoliation processes. One embodiment is a method for producing graphene comprising (i) performing electrolysis between an electrolysis anode and an electrolysis cathode in a molten carbonate electrolyte to generate carbon nanomaterial on the cathode, and (ii) electrochemically exfoliating the carbon nanomaterial from a second anode to produce graphene. The exfoliating step produces graphene in high yield than thicker, conventional graphite exfoliation reactions. CO.sub.2 can be the sole reactant used to produce the valuable product as graphene. This can incentivize utilization of CO.sub.2, and unlike alternative products made from CO.sub.2 such as carbon monoxide or other fuels such as methane, use of the graphene product does not release this greenhouse gas back into the atmosphere.

A cathode is provided for electrolysis of water wherein the cathode material comprises a multi-principal element, transition metal dichalcogenide material that has four or more chemical elements and that is a single phase, solid solution. The pristine cathode material does not contain platinum as a principal (major) component. However, a cathode comprising a transition metal dichalcogenide having platinum (Pt) nanosized islands or precipitates disposed thereon is also provided.

A cathode is provided for electrolysis of water wherein the cathode material comprises a multi-principal element, transition metal dichalcogenide material that has four or more chemical elements and that is a single phase, solid solution. The pristine cathode material does not contain platinum as a principal (major) component. However, a cathode comprising a transition metal dichalcogenide having platinum (Pt) nanosized islands or precipitates disposed thereon is also provided.

Provided are an anode for electrolysis, which includes a metal base, and a catalyst layer disposed on at least one surface of the metal base, wherein the catalyst layer includes a composite metal oxide of ruthenium, iridium, titanium, and platinum, and a metal in the composite metal oxide does not include palladium, wherein, when the catalyst layer is equally divided into a plurality of pixels, a standard deviation of iridium compositions of the plurality of equally divided pixels is 0.40 or less, and a method of preparing the same.

Provided are an anode for electrolysis, which includes a metal base, and a catalyst layer disposed on at least one surface of the metal base, wherein the catalyst layer includes a composite metal oxide of ruthenium, iridium, titanium, and platinum, and a metal in the composite metal oxide does not include palladium, wherein, when the catalyst layer is equally divided into a plurality of pixels, a standard deviation of iridium compositions of the plurality of equally divided pixels is 0.40 or less, and a method of preparing the same.

A method for electrolysis of water and a method for preparing a catalyst for electrolysis of water are provided. The method for electrolysis of water includes using a high entropy alloy as a catalyst. Further, the method for preparing a catalyst for electrolysis of water includes the steps of placing a substrate in an aqueous electrolyte containing a high entropy alloy precursor and performing an electroplating process on the substrate to form a high entropy alloy catalyst on the substrate.

A method for electrolysis of water and a method for preparing a catalyst for electrolysis of water are provided. The method for electrolysis of water includes using a high entropy alloy as a catalyst. Further, the method for preparing a catalyst for electrolysis of water includes the steps of placing a substrate in an aqueous electrolyte containing a high entropy alloy precursor and performing an electroplating process on the substrate to form a high entropy alloy catalyst on the substrate.

An abrupt interface electroreduction catalyst includes a porous gas diffusion layer and a catalyst layer providing a sharp reaction interface. The electroreduction catalyst can be used for converting CO.sub.2 into a target product such as ethylene. The porous gas diffusion layer can be hydrophobic and configured for contacting gas-phase CO.sub.2 while the catalyst layer is disposed on and covers a reaction interface side of the porous gas diffusion layer. The catalyst layer has another side contacting an electrolyte and can be hydrophilic, composed a metal such as Cu and is sufficiently thin to prevent diffusion limitations of the reactant in the electrolyte and enhance selectivity for the target product. The electroreduction catalyst can be made by vapor deposition methods and can be used for electrochemical production of ethylene in reaction system.