# How to Make Big Electrodes for Splitting Water > This patent describes a simple, energy-saving way to create large, efficient catalyst electrodes using a mix of iron, cobalt, and nickel compounds through an electrical plating process. - **Patent:** US 20210123152 - **Original title:** Method for Preparing Large-area Catalyst Electrode - **Owner:** National Chung Shan Institute of Science and Technology NCSIST - **Status:** Active - **Times cited:** 21 - **Field:** energy, materials, chemical_manufacturing ## What it does The patent outlines a method for creating a "large-area catalyst electrode" that helps split water into hydrogen and oxygen. First, you mix specific metal compounds like iron sulfate, cobalt chloride, and nickel nitrate in a liquid solvent such as water or ethanol (Claim 1, 2, 3, 4, 5). Then, you place a negative electrode (cathode) and a positive electrode (anode) into this metal solution (Claim 1). Using a "two-electrode method," electricity is passed through the solution at a constant voltage (0.1V to 1V) or constant current (0.1A to 1A) for 1 to 20 minutes (Claim 9, 10). This process, called "cathodic electrochemical deposition," causes the metal compounds to form a coating on the cathode, which then becomes the finished catalyst electrode (Claim 1). For example, a graphite cathode could be coated with a nickel-cobalt-iron catalyst from a water-based solution. ## What it does NOT cover - Does not cover catalyst electrodes made without using all three specified metals: iron, cobalt, and nickel compounds. - Does not cover deposition methods other than "cathodic electrochemical deposition" (e.g., spraying, vacuum deposition). - Does not cover systems that use more than two electrodes during the deposition process. - Does not cover deposition processes that do not maintain a constant voltage or constant current. - Does not cover electrodes where the anode's area is smaller than the cathode's area. ## The clever bit The novelty lies in combining specific iron, cobalt, and nickel compounds with a straightforward, energy-efficient "cathodic electrochemical deposition" method to reliably produce large-area catalysts with "good dual-function water electrolysis catalytic property." ## Real-world examples 1. Water electrolyzers for green hydrogen production 2. Fuel cells 3. Industrial chemical reactors 4. Electrochemical energy storage devices ## Why it matters Efficient and large-scale water electrolysis is crucial for producing green hydrogen, a clean energy source. This patent aims to simplify the manufacturing of "large-area catalyst electrodes" which are key components in electrolyzers. By making the process "simple and energy-saving," it could help reduce the cost and increase the availability of these critical materials for clean energy technologies. ## Frequently asked questions ### What does How to Make Big Electrodes for Splitting Water cover? This patent describes a simple, energy-saving way to create large, efficient catalyst electrodes using a mix of iron, cobalt, and nickel compounds through an electrical plating process. ### Who owns patent US 20210123152? This patent is owned by National Chung Shan Institute of Science and Technology NCSIST. ### When does this patent expire? This patent is expected to expire on October 22, 2040, when the invention enters the public domain. ### What is patent US 20210123152 cited by? This patent has been cited by 21 later patents that build on its ideas. ### What problem does this patent solve? Efficient and large-scale water electrolysis is crucial for producing green hydrogen, a clean energy source. This patent aims to simplify the manufacturing of "large-area catalyst electrodes" which are key components in electrolyzers. By making the process "simple and energy-saving," it could help reduce the cost and increase the availability of these critical materials for clean energy technologies. ### What does this patent NOT cover? Does not cover catalyst electrodes made without using all three specified metals: iron, cobalt, and nickel compounds. **Full plain-English explainer:** https://patentbrief.org/patent/us/20210123152/method-for-preparing-large-area-catalyst-electrode **Original patent:** https://patents.google.com/patent/US20210123152 --- _Source: PatentBrief — https://patentbrief.org. Patent facts are from public records; the plain-English explanation is PatentBrief's._ ## Related patents Semantically similar inventions in the PatentBrief corpus: - [How to Make Hydrogen Gas and Cupric Chloride Using an Electrolysis Cell](https://patentbrief.org/patent/us/8636880/electrolysis-cell-for-the-conversion-of-cuprous-chloride-in-hydrochloric-acid-to) — This patent describes an electrochemical cell that uses cuprous chloride in hydrochloric acid to produce hydrogen gas and cupric chloride, separated by a special membrane. - [Dome-Shaped Plates for Efficient Hydrogen Production in Electrolyzers](https://patentbrief.org/patent/us/20250027216/electrolyzer) — This patent describes an electrolyzer that uses uniquely dome-shaped plates to improve how water is split into hydrogen and oxygen, enhancing efficiency and product separation. - [Making Chemicals from Carbon Dioxide and Steam Using Electricity](https://patentbrief.org/patent/us/20110132770/process-for-producing-compounds-of-the-cxhyoz-type-by-reduction-of-carbon-dioxid) — This patent describes a process that uses electricity to split steam and then reacts the resulting hydrogen with carbon dioxide or carbon monoxide to create various carbon-based compounds, like fuels or plastics. - [Making Caustic Soda with Less Salt Using a Special Electrolysis Cell](https://patentbrief.org/patent/us/9181624/method-of-electrolysis-employing-two-chamber-ion-exchange-membrane-electrolytic-) — This patent describes a method to make purer caustic soda and chlorine gas using a two-chamber electrolysis cell with a gas diffusion electrode by carefully controlling pressure differences. - [Recycling Lithium-Ion Batteries to Make New Cathode Materials](https://patentbrief.org/patent/us/10522884/method-and-apparatus-for-recycling-lithium-ion-batteries) — This patent describes a method for recycling used lithium-ion batteries by dissolving their cathode materials, adjusting the metal ratios in a liquid, and then pulling out a custom mix of materials for new batteries without needing extreme heat.