Proposed is an iridium alloy catalyst having reversible catalytic activity for an oxygen evolution reaction (OER), a hydrogen evolution reaction (HER), and a hydrogen oxidation reaction (HOR) by including an iridium alloy including iridium (Ir) and nickel (Ni). The iridium alloy catalyst according to the present disclosure is rapidly converted to an iridium alloy catalyst in an oxide form and an iridium alloy catalyst in a metallic form according to applied voltage by controlling its crystallinity. Thus, even in case an oxide layer is formed after the OER, the oxidation layer disappears during the HER and HOR and the properties of an iridium metal catalyst remain, thereby maintaining HER/HOR performance.

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.

The present invention relates to a manufacturing apparatus and method for customizing a H.sub.2/CO synthetic gas in a desired ratio by producing a synthetic gas in which H.sub.2 and CO are mixed through hydrolysis of both carbon dioxide and a nitrogen compound with low power. In a low-power electrochemical apparatus for producing a synthetic gas according to the present invention, by performing the reduction of the carbon dioxide at the cathode and the oxidation of the nitrogen compound at the anode at the same time, carbon dioxide conversion efficiency may be improved 30% or more compared to the conventional carbon dioxide conversion system, and a synthetic gas with a desired H.sub.2/CO ratio may be produced by controlling the H.sub.2/CO ratio of the produced synthetic gas, and by reducing a driving voltage, the corrosion problem of electrode materials may be inhibited and the durability of electrodes may be increased.

An electrochemical electrode according to the present invention may prevent agglomeration and desorption of a catalyst even when a catalyst in a particle form is used, because a protective layer containing hydrogel is used, such that stability may be secured, thereby implementing an electrode having a long duration.

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.

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.

A stable three-dimensional core-shell metal-nitride catalyst consisting of NiFeN nanoparticles decorated on NiMoN nanorods supported on porous Ni foam (NiMoN@NiFeN), which functions as an oxygen evolution reaction catalyst for alkaline seawater electrolysis. It yields large current densities of 500 and 1000 mA cm.sup.−2 at overpotentials of 369 and 398 mV, respectively, in alkaline natural seawater at 25° C. Combined with an efficient hydrogen evolution reaction catalyst of NiMoN nanorods, current densities of 500 and 1000 mA cm.sup.−2 at low voltages of 1.608 and 1.709 V, respectively are achieved for overall alkaline seawater splitting at 60° C.

A stable three-dimensional core-shell metal-nitride catalyst consisting of NiFeN nanoparticles decorated on NiMoN nanorods supported on porous Ni foam (NiMoN@NiFeN), which functions as an oxygen evolution reaction catalyst for alkaline seawater electrolysis. It yields large current densities of 500 and 1000 mA cm.sup.−2 at overpotentials of 369 and 398 mV, respectively, in alkaline natural seawater at 25° C. Combined with an efficient hydrogen evolution reaction catalyst of NiMoN nanorods, current densities of 500 and 1000 mA cm.sup.−2 at low voltages of 1.608 and 1.709 V, respectively are achieved for overall alkaline seawater splitting at 60° C.

A capillary electrolysis in alkaline solution to produce hydrogen has a container having a plurality of polarized electrodes immersed in a chemical solution. A power source to generate the required electricity to produce a chemical reaction between the chemical solution and the electrodes.