Electrolyzer electrocatalyst comprising cobalt oxide (CO), zirconium (Zr) and a precious metal, an electrode comprising said electrocatalyst, and use of the electrocatalyst in an electrolysis process

Abstract

An electrolytic cell electrocatalyst comprising cobalt oxide (Co), zirconium (Zr) and a precious metal; an electrode for use in an electrolytic cell, the electrode comprising a support and a coating comprising the electrocatalyst; an electrochemical system comprising an electrolytic cell having an electrode comprising the electrocatalyst; use of the electrocatalyst to catalyze an electrolysis process; a method for electrolyzing water using the electrocatalyst; and a method for manufacturing an electrode comprising the electrocatalyst.

Description

[Technical field]

[0001] Electrolysis is a promising option for producing carbon-free hydrogen from renewable and nuclear sources. Electrolysis is the process of splitting water into hydrogen and oxygen using electricity. The electrolysis process takes place in units called electrolyzers. Electrolyzers can range in size from small appliance-sized equipment suitable for small-scale decentralized hydrogen production to large centralized production facilities that can, for example, be directly connected to renewables or other forms of electricity production that do not emit greenhouse gases. [Background technology]

[0002] In 2021, the U.S. Department of Energy (DOE) set a goal to reduce the cost of clean hydrogen by 80% to $1 per kilogram in 10 years. The goal of reducing the cost of producing hydrogen to $1 per kilogram in 10 years is called the Hydrogen "111" initiative. Electrolysis is the primary hydrogen production route to achieve this goal.

[0003] Hydrogen produced by electrolysis can have zero greenhouse gas emissions, depending on the electricity source used. When evaluating the benefits and economics of hydrogen production by electrolysis, one must consider its cost and efficiency, as well as the source of the electricity required, including emissions from electricity generation. In many parts of the world, today's power grids are not suitable to provide the electricity needed for electrolysis. This is due to the greenhouse gas emissions that are emitted during the actual generation of electricity, and the amount of fuel required to generate electricity due to the low efficiency of the electricity generation process.

[0004] Hydrogen production by electrolysis is being pursued as an alternative to renewable and nuclear energy sources, including wind, solar, hydroelectric, and geothermal energy production. These pathways would have virtually zero greenhouse gas and criteria pollutant emissions if the electricity used for electrolysis were derived from renewable energy sources. Additionally, it is important that the overall production cost of energy falls substantially in order to compete with more mature carbon-based pathways, such as natural gas reforming.

[0005] In view of the above, there is an increasing need for improved electrolytic cells with improved energy efficiency and life span. In particular, there appears to be a need to provide improved coatings for electrodes used in electrolytic cells, for example for oxygen evolution as a target reaction. Summary of the Invention

[0006] According to a first aspect, the present disclosure relates to an electrolyzer electrocatalyst comprising cobalt oxide (Co), zirconium (Zr) and a precious metal.

[0007] According to a second aspect, the present disclosure relates to an electrode for use in an electrolytic cell, said electrode comprising a support and a coating, said coating comprising cobalt oxide (Co), zirconium (Zr) and a precious metal.

[0008] According to a third aspect, the present disclosure relates to an electrochemical system including an electrolytic cell having a cathode, an anode, and an electrolytic solution or electrolyte, the cathode, the anode, or both the cathode and the anode including an electrocatalyst, the electrocatalyst including cobalt oxide (Co), zirconium (Zr), and a precious metal.

[0009] According to a fourth aspect, the present disclosure relates to the use of an electrocatalyst for catalyzing an electrolytic process, said electrocatalyst comprising cobalt oxide (Co), zirconium (Zr) and a precious metal.

[0010] According to a fifth aspect, the present disclosure relates to a method for water electrolysis, the method comprising: (i) providing a water electrolysis cell including an anode, a cathode, and an electrolytic solution or electrolyte, wherein at least one of the anode and the cathode includes an electrode catalyst comprising cobalt oxide (Co), zirconium (Zr), and a precious metal; (ii) contacting water with a water electrolysis cell; (iii) generating an electrical bias between the cathode and the anode; and (iv) producing hydrogen and / or oxygen; Equipped with.

[0011] According to a sixth aspect, the present invention relates to the use of a cathode electrocatalyst comprising cobalt oxide (Co), zirconium (Zr) and a noble metal for producing hydrogen via an electrolysis process.

[0012] According to a seventh aspect, the present disclosure relates to a method of manufacturing an electrode for use in an electrolytic cell, the electrode comprising a support and a coating, the method comprising: - providing a metal support comprising nickel (Ni) or titanium (Ti); - applying a coating comprising cobalt (Co), zirconium (Zr) and a precious metal onto said support; and - heating said substrate containing the coating in air; Equipped with. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 shows an exemplary embodiment of an electrolytic cell 10 in the prior art. [Diagram 2] FIG. 2 shows the effect of the addition of zirconium and ruthenium to the cobalt oxide coating on the initial potential (Ei) of the coated electrode. [Diagram 3] FIG. 3 shows the lifetime of the cobalt oxide coating in units of total current per surface area (kAh / m2) before coating passivation compared to the cobalt loading in the coating. [Figure 4] 4a and 4b show the lifetime and initial potential, respectively, of cobalt oxide coatings with a fixed cobalt / ruthenium mass ratio and varying zirconium mass fraction. [Diagram 5] 5a and 5b show the lifetime versus initial potential for cobalt oxide coatings with a fixed cobalt / zirconium ratio and increasing ruthenium loading. [Figure 6a] FIG. 6a shows the results of short-term electrolysis experiments carried out at 10 kA / m2 on a nickel plate and a nickel support with a titanium support and a cobalt / zirconium / ruthenium coating, respectively. [Figure 6b] FIG. 6b shows the relative wear rates of cobalt and zirconium measured on a Co / Zr / Ru coating on a titanium substrate. [Figure 7] FIG. 7 shows the results of measurements taken at 20° C. and 30% KOH using a nickel plate, a nickel supported electrode with a Co—Zr / Ru coating 100-9 / 1, and a titanium supported electrode. [Figure 8] FIG. 8 shows the results of tests conducted to evaluate the effect of using a cobalt oxide coating containing zirconium as a dispersant and gold (Au) to promote electrical conductivity throughout the bulk coating. [Figure 9] FIG. 9 shows the results of tests carried out to evaluate the activity effect of the Au-containing cobalt oxide coating. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] [Detailed Description of the Invention] The phrases and terms used in this disclosure are for the purpose of explanation and should not be considered limiting. As used herein, the term "plurality" refers to two or more items or components. The terms "comprising," "including," "carrying," "having," "containing," and "involving," whether in this specification or the claims, are open-ended terms, i.e., meaning "including but not limited to." Thus, the use of such terms is meant to encompass the items listed thereafter, and equivalents thereof, as well as additional items. With respect to the claims, only the transitional phrases "consisting of" and "consisting essentially of" are closed or semi-closed transitional phrases, respectively. In the claims, the use of ordinal terms such as "first," "second," "third," etc. to modify claim elements does not, in and of itself, imply a priority, precedence, or order of a claim element relative to other claim elements, or a chronological order in which a method is performed, but is merely used as a label to distinguish a claim element having a certain name from other claim elements having the same name (but using ordinal terms).

[0015] Hydrogen (H2) is an important raw material for various segments of the chemical industry, such as petrochemical and semiconductor manufacturing. In addition, it has great potential as a medium to make the global energy infrastructure more environmentally sustainable. Hydrogen can act as an alternative energy carrier to fossil fuels in a hydrogen economy and can also reduce CO2 emissions in energy-intensive applications such as steel and aluminum smelting.

[0016] The most prominent method to produce truly "green" hydrogen is water electrolysis, powered by renewable energy sources. However, water electrolysis suffers from energy inefficiency due to difficulties in catalytic reactions. Better electrocatalysts are needed to make this process more economically competitive.

[0017] The overall reaction of water electrolysis is as follows: [ka]

[0018] The process is carried out in either an acid or alkaline cell, where the acid cell uses a wet acid ion exchange membrane as the electrolyte, and the alkaline cell uses a concentrated aqueous base solution, typically in the range of 15-30 wt% KOH, as the electrolyte with a Zirfon separator.

[0019] Acidic systems have the advantages of being compact, having low electrolyte resistance, and having high gas separation capacity, which generally ranges from 10 to 30 kA / m 2 They can be operated at current densities as high as 10000 kcal / kg, making them more flexible in terms of increasing and decreasing activity. One of the main drawbacks is that this type of electrolyser relies on iridium as an electrocatalyst in the anode, which is expensive as it is a very rare element. Alkaline systems are much less dependent on critical materials, but are bulkier, have higher internal resistance, and are less power flexible. The overall reaction of the two electrochemical half-reactions consists of the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER), which can be explained as follows in acidic and alkaline electrolytes, respectively: [ka]

[0020] The largest energy loss comes from the anode half-reaction that evolves oxygen. A good electrocatalyst for this reaction would result in a smaller overpotential and higher energy efficiency. In this disclosure, we present electrodes with improved electrocatalysts.

[0021] 1 shows an exemplary embodiment of an electrolytic cell 10 to illustrate the basic principles of electrolysis. The electrolytic cell 10 comprises a vessel 11 containing an alkaline solution of sodium hydroxide or potassium hydroxide as an electrolyte 12.

[0022] The electrolytic cell 10 further includes an anode 21 and a cathode 22 disposed in the electrolyte 12. The anode 21 and the cathode 22 are connected to a source of electrical energy 30. In the electrolytic cell 10, a diaphragm 13 is disposed between the anode 21 and the cathode 22.

[0023] As shown in FIG. 1, an alkaline electrolytic cell generally transfers hydroxide ions (OH - The generation of oxygen on the anode 21 side is indicated by reference number 41. The generation of hydrogen on the cathode 22 side is indicated by reference number 42.

[0024] Electrolysers using alkaline solutions of sodium hydroxide or potassium hydroxide as electrolytes have been commercially available for many years. One of the important parameters of alkaline hydrolysis is the type of electrodes and coatings used. Oxygen evolution in alkaline water electrolysers is typically catalysed with anodes made of bulk nickel, bulk steel, or nickel-coated steel. These materials have a long life span but a relatively high overpotential for oxygen evolution. One of the consequences is a relatively high level of corrosion, for example for steel-based anodes. The specific circumstances of this corrosion are currently not well understood. In terms of corrosion prevention, the anodes 21 and cathodes 22 used in electrolysers 10 typically include a suitable coating to improve the life span of the electrodes.

[0025] In the prior art, an alternative for producing electrolytic cells is known, which uses a solid alkaline exchange membrane (AEM) as electrolyte, which can be used together with pure water or a KOH solution as additional electrolyte. These alternatives, which use anion exchange membranes to separate the anodic and cathodic compartments, have shown promise on a laboratory scale. The present disclosure relates to electrocatalysts used in the form of coatings on electrodes, particularly the anode 21, which can improve the properties of the electrodes, in particular their lifetime. The coating according to the present disclosure is directed to oxygen evolution as the target reaction. The coating is a cobalt oxide (Co) based coating with zirconium (Zr) as a dispersant and a precious metal to promote electrical conductivity throughout the bulk coating. According to the present disclosure, the precious metal is preferably selected from ruthenium (Ru), gold (Au), iridium (Ir), platinum (Pt) and palladium (Pd), and as explained in more detail below, it has been demonstrated that the lifetime of coatings containing cobalt oxide, zirconium, and in particular ruthenium and / or gold, is much higher than known coatings. The coatings described in the present disclosure provide a longer lifetime than other known Ni alternatives, such as Ni-Fe oxyhydroxide, due to the much higher robustness of cobalt oxide.

[0026] In one embodiment, an anode comprising a cobalt oxide coating made of Zr, Ru and / or Au can catalyze oxygen evolution at low overpotentials due to the relatively high electrochemical activity of cobalt and can benefit from the incorporation of Zr as a dispersant and Ru and / or Au to promote electrical conductivity throughout the bulk coating.

[0027] According to the present disclosure, the aforementioned coatings, including cobalt oxide, zirconium, and a precious metal, such as ruthenium or gold, are deposited on a suitable metal substrate. Preferably, the coatings are deposited on a titanium (Ti) or nickel (Ni) substrate. Alternatively, the substrate includes a titanium alloy, a nickel alloy, steel, or stainless steel.

[0028] Titanium is a particularly attractive substrate due to its dimensional stability and high availability. A known drawback of using titanium as a support material for obtaining electrodes is the risk of the formation of an electrically insulating oxide interlayer during the preparation of the coating or during the actual electrolysis. However, according to the present disclosure, the risk of the formation of such an electrically insulating oxide interlayer is countered by the presence of Ru in the coating, which has the ability to form a passivation-resistant interlayer at the titanium-coating interface.

[0029] Nickel is particularly suitable for making electrodes because it is dimensionally stable and can interact strongly with Co by forming the NiCo2O4 spinel.

[0030] Cobalt oxide (Co3O4) is a well-known oxygen evolution electrocatalyst and, together with a mixture of nickel iron oxide and cobalt iron oxide, is one of the most efficient materials for generating electricity. This means that the material can be used at low overpotentials. This material has a lower overpotential than nickel oxide grown on bulk Ni, which is currently the standard material for alkaline electrolyzers, and tends to deactivate over time.

[0031] To utilize Co3O4 layers in alkaline electrolysers, significant layer thicknesses must be deposited, and the cobalt depletion rate during operation has been found to be comparable to that of iridium oxide, a rare and expensive state-of-the-art electrocatalyst, but the extremely high lifetime requirements of alkaline electrolysers necessitate significant loadings. However, the poor bulk electrical conductivity of Co3O4 makes it unfeasible to form thick layers of preformed oxide.

[0032] In one embodiment, an attempt to circumvent this problem is achieved by adding to the Co3O4 layer both a) Zr and b) Ru or Au, where a) acts as a dispersant to increase the volume and active surface area of ​​the electrocatalyst, and b) acts as a conductive agent to improve the electrical conductivity of the bulk coating and prevent the formation of a passivation layer at the interface of the coating with the bulk metal support during repeated firing in air and electrolytic operation of the coating.

[0033] In accordance with the present disclosure, it has surprisingly been demonstrated that the combination of very small amounts of zirconium and very small amounts of precious metals, such as ruthenium and gold, significantly alters and improves the properties of coatings containing cobalt oxide, especially when oxygen evolution is taken into account.

[0034] It should be noted that the coatings according to the present disclosure allow electrolysers using the coated electrodes, particularly anodes, to operate at higher power efficiency, which is a key factor in determining OPEX, or operating expenses. If the efficiency gains at high current densities are sufficient, a smaller stack size may be required, reducing CAPEX, or capital expenditure.

[0035] 2 and 3 show the beneficial effect of including zirconium and ruthenium in cobalt oxide on oxygen evolution electrolysis.

[0036] Figure 2 shows the effect of the addition of zirconium and ruthenium to the cobalt oxide coating on the initial potential (Ei) shown on the Y-axis. The X-axis shows the cobalt loading of the coating. Figure 2 is for a cobalt oxide coating on a titanium substrate.

[0037] Figure 2 shows the relationship between the amount of cobalt loaded and the initial potential (Ei) for pure Co3O4 deposited on a titanium support. As shown in Figure 2, pure Co3O4 deposited on titanium exhibits a gradual increase in electrode potential as a function of the amount of cobalt loaded.

[0038] Furthermore, the addition of zirconium alone reduces the electrode potential at low cobalt loadings, but the potential increases rapidly as the cobalt loading increases, as shown in Figure 2. Figure 2 clearly shows that the addition of small amounts of ruthenium in addition to zirconium significantly reduces the electrode potential over the entire range from low to high cobalt loadings.

[0039] In the example of Figure 2, ruthenium is present in a mass ratio of 5% relative to cobalt. This means that for every gram of cobalt in the coating, there is 0.05 grams of ruthenium. Considering the price of ruthenium, it is important to note that even very small amounts already have a beneficial effect on the properties of the coating.

[0040] Figure 3 shows the life of the cobalt oxide coating on the Y axis, the amount of cobalt in the coating on the X axis, and the total current per surface area before coating deactivation (kAh / m 2 ) is shown in Figure 3. The effect of adding zirconium to the coating and the effect of adding both zirconium and ruthenium to the coating is shown in Figure 3. Figure 3 shows a cobalt oxide coating on a titanium substrate.

[0041] According to Figure 3, pure Co3O4 coatings deposited on titanium show a linear increase in coating life as a function of cobalt loading. Figure 3 further shows that the addition of zirconium has a beneficial effect on coating life, with the addition of zirconium clearly increasing life at low cobalt loadings. Coatings containing zirconium show a linear trend in increased life associated with increasing cobalt loading, but at higher cobalt loadings the beneficial effect is lost.

[0042] Finally, Figure 3 shows that the further addition of ruthenium increases the coating life at low cobalt loadings to a level comparable to that of a coating comprised solely of zirconium. However, coatings comprised of both zirconium and ruthenium continue to show a linear increase in coating life as the cobalt loading increases. In the example of Figure 3, a small amount of ruthenium, 5% by weight relative to cobalt, is used to achieve the beneficial effects shown. As shown, the ruthenium-containing coating has a similar effect at low cobalt loadings as coatings comprised solely of zirconium, but the effect is no longer limited to low cobalt loadings.

[0043] It should be noted that the results shown in Figures 2 and 3 were obtained using electrodes having cobalt oxide coatings formed by spin-coating aqueous solutions of metal salt precursors onto titanium substrates that had previously been etched with hydrochloric acid (HCl).

[0044] Generally, the coating can be painted onto the support. According to one embodiment, a viscosity modifier is added before the step of applying the coating. A suitable viscosity modifier for use in the manufacture of electrodes according to the present disclosure is polyethylene glycol.

[0045] After applying the coating onto the substrate, the process involves pyrolysis for 15 minutes in air at 400° C., i.e., the titanium substrate is heated in an oven. The aforementioned heating step can be carried out at a temperature between about 300° C. and 600° C., preferably between about 350° C. and 450° C.

[0046] The metal salts referred to above may consist of, for example, CoCl2, RuCl3, and ZrCl2. Alternatively, the salts may consist of Co(NO3)2, Zr(NO3)2, and Ru(No)(NO3).

[0047] The electrode thus obtained was then charged at 600 A / m in a strong acid (H2SO4; 25%).2 Although the coating is intended for use under strongly alkaline conditions, electrolysis in strong acid serves as an accelerated life test, since, due to the nature of the oxygen evolution reaction, localized acidification of the catalyst surface is one of the main degradation mechanisms.

[0048] The dispersion effect of zirconium and the conductivity promotion effect of ruthenium were further analyzed by varying their fractions, focusing on their influence on the initial potential and the lifetime of the coating.

[0049] Figures 4a and 4b show the lifetime and initial potential, respectively, of cobalt oxide coatings with a fixed cobalt / ruthenium mass ratio and varying zirconium mass fractions. In the examples of Figures 4a and 4b, the cobalt / ruthenium mass ratio is equal to 20, i.e. the coating is composed of 0.05 grams of ruthenium for every gram of cobalt. In the examples of Figures 4a and 4b, the cobalt loading of the coating is about 2.1 g / m for each sample. 2 In the example of Figures 4a and 4b, the coating is applied onto a titanium substrate.

[0050] Figure 4a shows that the addition of zirconium increases the lifetime up to a zirconium / cobalt mass fraction of about 25%. Increasing zirconium up to a zirconium / cobalt mass fraction of 50% decreases the coating lifetime.

[0051] FIG. 4b shows that when ruthenium is present in the coating in addition to zirconium, as in the example of FIG. 4b, increasing the zirconium above about 5 wt. % has no apparent positive effect on the initial potential.

[0052] Figures 5a and 5b show the lifetime vs. initial potential for cobalt oxide coatings with a fixed cobalt / zirconium ratio and increasing ruthenium loading. In the example of Figures 5a and 5b, the cobalt / zirconium mass ratio is equal to 10, which means 0.1 grams of zirconium for every gram of cobalt. Furthermore, in the example of Figures 5a and 5b, the cobalt loading is about 2.3 g / m 2 Note that in the example of Figures 4a and 4b, the coating is applied onto a titanium substrate.

[0053] Figure 5a shows that the addition of ruthenium above the minimum of 2.5% by mass of cobalt does not significantly affect the lifetime of the coating, presumably due to the low amount of ruthenium in the coating compared to the amount of cobalt.

[0054] Figure 5b shows that as the ruthenium / cobalt ratio increases, the potential decreases. The reason for this phenomenon is probably that RuO2 (an efficient oxygen evolution catalyst in itself) starts to take part in the reaction itself. The beneficial effect on the potential is already evident at very small ruthenium concentrations. A pure RuO2 sample with a similar loading is shown as a reference. FIG. 6a shows the results of the 10 kA / m2 test for a nickel plate and a nickel substrate coated with cobalt / zirconium / ruthenium, with the cobalt / zirconium mass ratio of 10 and the cobalt / ruthenium mass ratio of 80, respectively. 2 The results of a short-term electrolysis experiment conducted at 600 s are shown in Fig. 6a. The cobalt loading of the coating in Fig. 6a is about 3.5 g / m 2 Figure 6a shows that the Co / Zr / Ru coated substrate has a lower (over)potential than pure Ni.

[0055] Figure 6b shows the relative wear rates of cobalt and zirconium measured on a Co / Zr / Ru coating on a titanium substrate. The cobalt loading associated with Figure 6b is approximately 10 grams / m 2 It is.

[0056] The experiment shown in FIG. 6b was carried out in 30% KOH at a temperature of 50° C.

[0057] Figure 7 shows the results of measurements in 30% KOH at 20°C using nickel plates and nickel and titanium supported electrodes with Co-Zr / Ru coating 100-9 / 1. Because nickel is sensitive to acids, these tests were limited to 30% KOH electrolyte. The Y-axis in Figure 7 shows the current density.

[0058] The Co-Zr / Ru 100-9 / 1 coating obviously improved the activity of the nickel-supported electrode compared with pure nickel, but the effect was not as high as that of the titanium-supported electrode.

[0059] The difference in effectiveness of the coating on nickel and titanium substrates is presumably due to the ruthenium component being less efficient at promoting electrical conductivity when the substrate is nickel rather than titanium. Short-term stability is adequate on both substrates.

[0060] The data shown in Figure 7 was obtained using cyclic voltammetry at 10 mVs -1 The images were recorded at a scan rate of 100 Hz.

[0061] Figure 8 shows the results of tests conducted to evaluate the effect of using cobalt oxide coatings with zirconium and gold (Au) as dispersants to promote electrical conductivity throughout the bulk coating. Four different coatings, namely, 1) Pure cobalt oxide (Co3O4), 2) Cobalt oxide coating containing gold (Co3O4-AU), 3) a cobalt oxide coating made of zirconium and gold (Co3O4-ZrO2 / Au), and 4) Cobalt oxide coating consisting of zirconium and ruthenium (Co3O4-ZrO2 / RuO2) The efficiency of the life-enhancing effect of the coating was tested.

[0062] According to the tests shown in FIG. 8, instead of using ruthenium as a promoter, gold was incorporated into the coating.

[0063] As shown in FIG. 8, the presence of gold in the cobalt oxide coating was found to have a beneficial effect on the life of the coating when the coating also contained zirconium as a dispersant.

[0064] The coating of FIG. 8 has a cobalt / gold mass ratio of 200.

[0065] The data for the cobalt oxide coatings consisting of zirconium and ruthenium in Figure 8 are for the Co-ZR / RU l100-9 / 1 electrode and are shown in Figure 8 for reference. The lifetime in accelerated life tests with 25% H2SO4 was also improved compared to pure cobalt oxide, but only when ZrO2 was also included. From the characterization cyclic voltammograms it appears that the inclusion of gold, like ruthenium, promotes the conductivity of the coating.

[0066] Tests performed to evaluate the activity of using cobalt oxide coatings containing Au are shown in Figure 9. The effect of Au on activity was also tested using cyclic voltammetry at 20°C in a 30% KOH electrolyte. The Co-Au coating shows higher activity than pure nickel, but the improvement is not as great as the Co / Zr / Ru coating.

Claims

1. An electrocatalyst for an electrolytic cell, the electrocatalyst comprising cobalt oxide (Co), zirconium (Zr), and a noble metal.

2. 2. The electrocatalyst of claim 1, wherein the noble metal is selected from ruthenium (Ru), gold (Au), iridium (Ir), platinum (Pt) and palladium (Pd).

3. 10. The electrocatalyst of claim 1, wherein the mass fraction of zirconium relative to cobalt (Co) is about 2% to 20%.

4. 10. The electrocatalyst of claim 1, wherein the mass fraction of the noble metal relative to cobalt (Co) is about 0.5% to 20%.

5. 10. An electrode for use in an electrolytic cell, said electrode comprising a support and a coating, said coating being an electrocatalyst for an electrolytic cell according to claim 1.

6. 6. The electrode of claim 5, wherein the cobalt (Co) loading in the coating is about 2-25 g / m2.

7. 10. An electrochemical system comprising an electrolytic cell having a cathode, an anode, and an electrolytic solution or electrolyte, wherein at least one of the cathode and the anode comprises the electrocatalyst of claim 1.

8. An electrochemical system as described in claim 7, wherein at least one of the cathode and the anode is an electrode as described in claim 5.

9. 10. Use of the electrocatalyst of claim 1 for catalyzing an electrolytic process.

10. 10. The use of claim 9, wherein the electrolysis process is carried out by the electrochemical system of claim 7.

11. 11. The use according to claim 10, wherein the electrolysis process is water electrolysis and the electrocatalyst is used to catalyze the production of oxygen at the anode and / or the production of hydrogen at the cathode.

12. 1. A method of manufacturing an electrode for use in an electrolytic cell, comprising: - providing a metal support; - applying a coating comprising cobalt (Co), zirconium (Zr) and a noble metal onto said substrate; and - heating the substrate containing the coating in air; A method comprising:

13. 13. The method of claim 12, wherein the step of applying a coating containing cobalt (Co), zirconium (Zr) and a noble metal onto the substrate comprises: - applying the coating by spreading an aqueous solution of metal salt precursors containing cobalt (Co), zirconium (Zr) and a noble metal onto the substrate; The method comprises:

14. 13. The method of claim 12, further comprising adding a viscosity modifier prior to applying the coating.

15. The method of claim 12, further comprising heating the substrate with the coating at a temperature between 300°C and 600°C.

16. 13. The method of claim 12, wherein preparing the metal support comprises etching the support with hydrochloric acid (HCL).

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