CN102168283B - Electrode coating and preparation method thereof - Google Patents
Electrode coating and preparation method thereof Download PDFInfo
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- CN102168283B CN102168283B CN201110087919.5A CN201110087919A CN102168283B CN 102168283 B CN102168283 B CN 102168283B CN 201110087919 A CN201110087919 A CN 201110087919A CN 102168283 B CN102168283 B CN 102168283B
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Abstract
The invention discloses a high-adhesiveness durable electrode coating and a preparation method thereof. The electrode coating is prepared by adding a coordination compound into an iridium-tantalum coating, wherein the coordinator is one, two or three of alkyl group, amino group and nitro-group, and the coordinating element is one of molybdenum (Mo), tin (Sn), platinum (Pt), cobalt (Co), manganese (Mn) and titanium (Ti). The product disclosed by the invention uses the coating obtained from the organic coordination compound containing the elements, thus, can well resist acid, erosion of massive gas and impact of high current density, and has favorable cohesive property with the substrate; the service life of the electrode is prolonged; and the method is simple to operate, does not need complicated substrate pretreatment technology, and does not need a complicated middle layer or the like.
Description
Technical field
The present invention relates to a kind of electrode, specifically electrode coating and preparation method thereof.
Background technology
Take metal titanium or other valve shaped metals is base material, take and have the electrode that the mixed metal oxide (being generally precious metal and other plain metal hopcalites) of electrocatalysis characteristic is coating, it is well-known in industries such as multiple electrochemical field such as electrolysis, plating, chlor-alkali, Organic Electricity are synthetic, being employed in a large number.The traditional thermal decomposition method of the general use of this coated anode, will contain the solution of catalytic performance metallics, and brushing is in layer on the process pure titanium plate of certain pre-treatment.By this method, the coating of acquisition and the non-metallurgical binding of the combination between matrix.By the observation of scanning electron microscope, coating is irregular polygon cracking, and coating porosity is higher.Electrode in use, can produce a large amount of gas, in some cases, in chlor-alkali or hypochlorite industry, is the target product of production or the target product of certain flow process; But in most industry, just as side reaction, exist, such as oxygen or the chlorine of electroplating process Anodic generation.The gassing reaction of this fierceness has produced bad impact for the life-span of coating, major cause is that these gases when separating out from segmentation crack, the mechanical effect of fiercely washing away at the bubble of the formation of coatingsurface, especially in the higher environment of current density, this strong gassing reaction may cause originally just having the phenomenons such as peeling off more easily appears in the coating of a large amount of be full of cracks, thus the life-span of having reduced anode.Under conventional corrosive environment, the performance of the corrosion resistance nature of the catalyst coatings that contains precious metal is extremely excellent, even work under the more severe electrolysis of most corrosive environment or plating environment, also has good superiority.And due to the development of electrochemical industry, more and more harsher at some field environment, such as the thin copper foil field of electronic industry, or the zinc-plated industry of steel plate, due to the needs of producing, anodic current density obviously strengthens.Under this environment, oxygen evolution reaction is particularly violent, adds that working temperature is high again, and conventional noble metal electrode there will be the obvious phenomenon declining of life-span.
Summary of the invention
The problem existing for above-mentioned prior art, the object of this invention is to provide electrode coating of a kind of high-adhesiveness weather resistance and preparation method thereof, this electrode coating can improve the adhesivity of coating itself and base material, the segmentation crack number of coatingsurface is obviously reduced, compactness improves, thereby has extended the work-ing life of electrode.
To achieve these goals, technical scheme provided by the present invention is a kind of electrode coating of high-adhesiveness weather resistance, this electrode coating is added with coordination compound in iridium tantalum coating, wherein ligand is a kind of, two or three the combination in alkyl, amino and nitro, and coordination element is a kind of in molybdenum Mo, tin Sn, platinum Pt, cobalt Co, manganese Mn, titanium Ti.
A preparation method for the electrode coating of weather resistance, comprises the following steps:
Step 1, first by elemental indium tantalum Ir-Ta weight ratio 65: 35 and element gross weight, be 30g/m
2configuration iridium tantalum masking liquid, and add thinner g/ time according to metal iridium tantalum material loading total amount (0.8～1);
Step 2, according to coordination element in coordination compound and iridium weight ratio, be (5: 95)～(15: 85), in solution described in step 1, add coordination compound, stir fully after standing 1～2 hour, masking liquid is prepared complete;
Step 3, titanium base material is used after degreaser oil removing, the oxalic acid solution that is 10～15% at weight fraction or volume fraction are digestion 1～3 hour in 50% hydrochloric acid soln, then use deionized water or distilled water to clean, with raw spirit, rinse again afterwards, standby at air drying;
Step 4, the masking liquid brushing that the titanium base material use of handling well is configured are dried 10～15 minutes after having brushed at 100～150 ℃, then at 450～500 ℃, calcine 12～20 minutes, and repeatable operation repeatedly, is coated masking liquid;
Step 5, finally at 450～500 ℃, calcine 1～1.5 hour, obtain coating.
Beneficial effect: product of the present invention has been used and contained the coating that this element organic coordination compound obtains, the impact of the washing away of acidproof, resistance to a large amount of gases that can be fabulous, resistance to high current density, has good cohesiveness with matrix; Extended the work-ing life of electrode; Method is simple to operate, does not need complicated pretreatment of base material technology, does not need complicated middle layer etc.
Accompanying drawing explanation
Fig. 1 is the scanning electron microscope (SEM) photograph (* 2000 times) of various embodiments of the present invention 1;
Fig. 2 is the scanning electron microscope (SEM) photograph (* 2000 times) of various embodiments of the present invention 2;
Fig. 3 is the scanning electron microscope (SEM) photograph (* 2000 times) of various embodiments of the present invention 3;
Fig. 4 is the scanning electron microscope (SEM) photograph (* 2000 times) of various embodiments of the present invention 4;
Fig. 5 is the scanning electron microscope (SEM) photograph (* 2000 times) of various embodiments of the present invention 5;
Fig. 6 is the scanning electron microscope (SEM) photograph (* 2000 times) of various embodiments of the present invention 6;
Fig. 7 is the scanning electron microscope (SEM) photograph (* 2000 times) of comparative example.
Embodiment
Below in conjunction with the drawings and specific embodiments, further illustrate the present invention, the present embodiment is implemented take technical solution of the present invention under prerequisite, should understand these embodiment and only for the present invention is described, is not used in and limits the scope of the invention.
Embodiment mono-: a kind of electrode coating of high-adhesiveness weather resistance, and this electrode coating is added with coordination compound in iridium tantalum coating, and wherein ligand is amino, and coordination element is molybdenum Mo.
Its preparation method comprises the following steps:
Step 1, first by elemental indium tantalum Ir-Ta weight ratio 65: 35 and element gross weight, be 30g/m
2configuration iridium tantalum masking liquid, and add thinner propyl carbinol 0.8g/ time according to metal iridium tantalum material loading total amount;
Step 2, according to coordination molybdenum in coordination compound and iridium weight ratio 10: 90, in solution described in step 1, add coordination compound, stir fully after standing 1 hour, masking liquid is prepared complete;
Step 3, titanium base material is used after hot washing powder solution oil removing, in the oxalic acid solution that is 10% at weight fraction, digestion is 3 hours, then uses washed with de-ionized water, rinses afterwards with raw spirit again, standby at air drying;
Step 4, the masking liquid brushing that the titanium base material use of handling well is configured are dried 15 minutes after having brushed at 100 ℃, then at 500 ℃, calcine 12 minutes, and repeatable operation repeatedly, is coated masking liquid;
Step 5, finally at 500 ℃, calcine 1 hour, obtain coating.
Embodiment bis-: a kind of electrode coating of high-adhesiveness weather resistance, and this electrode coating is added with coordination compound in iridium tantalum coating, and wherein ligand is alkyl, and coordination element is tin Sn.
Its preparation method comprises the following steps:
Step 1, first by elemental indium tantalum Ir-Ta weight ratio 65: 35 and element gross weight, be 30g/m2 configuration iridium tantalum masking liquid, and according to 1g/ interpolation thinner propyl carbinol of metal iridium tantalum material loading total amount;
Step 2, according to coordination element tin in coordination compound and iridium weight ratio, to step 1 described in solution in add coordination compound at 5: 95, stir fully after standing 1.5 hours, masking liquid is prepared complete;
Step 3, titanium base material is used after the oil removing of chemical reagent acetone, the hydrochloric acid soln digestion that is 50% in volume fraction 1 hour, is used afterwards distilled water to clean, and then rinses with raw spirit, standby at air drying;
Step 4, by the masking liquid brushing configuring for the titanium base material handled well, after having brushed, at 110 ℃, dry 13 minutes, then at 450 ℃, calcine 15 minutes, repetitive operation repeatedly, is coated to masking liquid;
Step 5, finally at 450 ℃, calcine 1 hour, obtain coating.
Embodiment tri-: a kind of electrode coating of high-adhesiveness weather resistance, and this electrode coating is added with coordination compound in iridium tantalum coating, and wherein ligand is combination amino, nitro, and coordination element is platinum Pt.
Its preparation method comprises the following steps:
Step 1, first by elemental indium tantalum Ir-Ta weight ratio 65: 35 and element gross weight, be 30g/m
2configuration iridium tantalum masking liquid, and add thinner propyl carbinol 0.8g/ time according to metal iridium tantalum material loading total amount;
Step 2, according to coordination elements platinum in coordination compound and iridium weight ratio, be 8: 92, in solution described in step 1, add coordination compound, stir fully after standing 2 hours, masking liquid is prepared complete;
Step 3, titanium base material is used after the oil removing of chemical reagent acetone, in the oxalic acid solution that is 13% at weight fraction, digestion is 1.5 hours, then uses washed with de-ionized water, rinses afterwards with raw spirit again, treats that air drying is standby;
Step 4, the masking liquid brushing that the titanium base material use of handling well is configured are dried 15 minutes after having brushed at 120 ℃, then at 475 ℃, calcine 20 minutes, and repeatable operation repeatedly, is coated masking liquid;
Step 5, finally at 480 ℃, calcine 1 hour, obtain coating.
Embodiment tetra-: a kind of electrode coating of high-adhesiveness weather resistance, and this electrode coating is added with coordination compound in iridium tantalum coating, and wherein ligand is combination amino, nitro, and coordination element is cobalt Co.
Its preparation method comprises the following steps:
Step 1, first by elemental indium tantalum Ir-Ta weight ratio 65: 35 and element gross weight, be 30g/m
2configuration iridium tantalum masking liquid, and add thinner dehydrated alcohol 0.8g/ time according to metal iridium tantalum material loading total amount;
Step 2, according to coordination element cobalt in coordination compound and iridium weight ratio, be 15: 85, in solution described in step 1, add coordination compound, stir fully after standing 1 hour, masking liquid is prepared complete;
Step 3, titanium base material is used after the oil removing of chemical reagent acetone, in the oxalic acid solution that is 14% at weight fraction, digestion is 1 hour, then uses washed with de-ionized water, rinses afterwards with raw spirit again, treats that air drying is standby;
Step 4, the masking liquid brushing that the titanium base material use of handling well is configured are dried 10 minutes after having brushed at 130 ℃, then at 480 ℃, calcine 15 minutes, and repeatable operation repeatedly, is coated masking liquid;
Step 5, finally at 480 ℃, calcine 1 hour, obtain coating.
Embodiment five: a kind of electrode coating of high-adhesiveness weather resistance, and this electrode coating is added with coordination compound in iridium tantalum coating, and wherein ligand is the combination of amino, alkyl and nitro, and coordination element is manganese Mn.
Its preparation method comprises the following steps:
Step 1, first by elemental indium tantalum Ir-Ta weight ratio 65: 35 and element gross weight, be 30g/m
2configuration iridium tantalum masking liquid, and add thinner dehydrated alcohol 0.9g/ time according to metal iridium tantalum material loading total amount;
Step 2, according to coordination element manganese in coordination compound and iridium weight ratio, be 10: 90, in solution described in step 1, add coordination compound, stir fully after standing 2 hours, masking liquid is prepared complete;
Step 3, titanium base material is used after hot washing powder solution oil removing, in the oxalic acid solution that is 15% at weight fraction, digestion is 1 hour, then carries out deionized water rinsing, rinses afterwards with raw spirit again, treats that air drying is standby;
Step 4, the masking liquid brushing that the titanium base material use of handling well is configured are dried 10 minutes after having brushed at 140 ℃, then at 450 ℃, calcine 20 minutes, and repeatable operation repeatedly, is coated masking liquid;
Step 5, finally at 480 ℃, calcine 1.5 hours, obtain coating.
Embodiment six: a kind of electrode coating of high-adhesiveness weather resistance, and this electrode coating is added with coordination compound in iridium tantalum coating, and wherein ligand is nitro, and coordination element is titanium Ti.
Its preparation method, comprises the following steps:
Step 1, first by elemental indium tantalum Ir-Ta weight ratio 65: 35 and element gross weight, be 30g/m
2configuration iridium tantalum masking liquid, and add thinner dehydrated alcohol 1g/ time according to metal iridium tantalum material loading total amount;
Step 2, according to coordination element titanium in coordination compound and iridium weight ratio, be 10: 90, in solution described in step 1, add coordination compound, stir fully after standing 2 hours, masking liquid is prepared complete;
Step 3, titanium base material is used after the oil removing of chemical reagent acetone, in the hydrochloric acid soln that is 50% in volume fraction, digestion is 1.5 hours, then carries out washed with de-ionized water, rinses afterwards drying for standby with raw spirit again;
Step 4, the masking liquid brushing that the titanium base material use of handling well is configured are dried 15 minutes after having brushed at 150 ℃, then at 450 ℃, calcine 20 minutes, and repeatable operation repeatedly, is coated masking liquid;
Step 5, finally at 450 ℃, calcine 1.5 hours, obtain coating.
Comparative example: a kind of conventional electrodes coating, this electrode coating is common iridium tantalum coating.
Its preparation method comprises the following steps:
Step 1, first by elemental indium tantalum Ir-Ta weight ratio 65: 35 and element gross weight, be 30g/m
2configuration iridium tantalum masking liquid, and add diluent ethanol 1g/ time according to metal iridium tantalum material loading total amount, masking liquid is prepared complete stand-by;
Step 2, titanium base material is used after degreaser oil removing, in the oxalic acid solution that is 15% at weight fraction, digestion is 1 hour, then carries out deionized water rinsing, rinses afterwards drying for standby with raw spirit again;
Step 3, the masking liquid brushing that the titanium base material use of handling well is configured are dried 12 minutes after having brushed at 150 ℃, then at 500 ℃, calcine 10 minutes, and repeatable operation repeatedly, is coated masking liquid;
Step 4, finally at 500 ℃, calcine 1 hour, obtain coating.
The coated electrode of embodiment 1-6 and comparative example acquisition is cut into the sample that is of a size of 1cm*1cm, as analysing oxygen anodes, carry out accelerated aging test, in the sulphuric acid soln that is 1mol/L in concentration, carry out the impact of the large electric current of 40kA/m2, using and surpass starting voltage 8V as test terminal, test result is in Table 1.
Each embodiment of table 1 and comparative example electrode sample accelerated aging data
| Sequence | Accelerated aging value |
| Embodiment 1 | 2600h |
| Embodiment 2 | 1668h |
| Embodiment 3 | 1598h |
| Embodiment 4 | 2242h |
| Embodiment 5 | 1725h |
| Embodiment 6 | 1996h |
| Comparative example | 1574h |
Claims (3)
1. a preparation method for the electrode coating of high-adhesiveness weather resistance, is characterized in that comprising the following steps:
Step 1, first by elemental indium tantalum Ir-Ta weight ratio 65:35 and element gross weight, be 30g/m
2configuration iridium tantalum masking liquid, and add thinner g/ time according to metal iridium tantalum material loading total amount (0.8～1);
Step 2, according to coordination element in coordination compound and iridium weight ratio, be (5:95)～(15:85), in solution described in step 1, add coordination compound, stir fully after standing 1～2 hour, masking liquid is prepared complete;
Step 3, titanium base material is used after degreaser oil removing, the oxalic acid solution that is 10～15% at weight fraction or volume fraction are digestion 1～3 hour in 50% hydrochloric acid soln, then use deionized water or distilled water to clean, with raw spirit, rinse again afterwards, standby at air drying;
Step 4, the masking liquid brushing that the titanium base material use of handling well is configured are dried 10～15 minutes after having brushed at 100～150 ℃, then at 450～500 ℃, calcine 12～20 minutes, and repeatable operation repeatedly, is coated masking liquid;
Step 5, finally at 450～500 ℃, calcine 1～1.5 hour, obtain coating;
In described coordination compound, ligand is a kind of, two or three the combination in alkyl, amino and nitro, and coordination element is a kind of in molybdenum Mo, tin Sn, platinum Pt, cobalt Co, manganese Mn, titanium Ti.
2. a kind of preparation method of electrode coating of high-adhesiveness weather resistance according to claim 1, is characterized in that: in described step 1, thinner is dehydrated alcohol or propyl carbinol.
3. a kind of preparation method of electrode coating of high-adhesiveness weather resistance according to claim 1, is characterized in that: in described step 3, degreaser is hot washing powder solution or chemical reagent acetone.
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| WO2013099780A2 (en) * | 2011-12-26 | 2013-07-04 | Permelec Electrode Ltd. | High-load durable anode for oxygen generation and manufacturing method for the same |
| CN104289309A (en) * | 2014-10-16 | 2015-01-21 | 南通市崇川盛源净化器材厂 | Electric dust removal device and catalyst coating formula |
| CN104480490B (en) * | 2014-12-08 | 2016-10-05 | 青岛双瑞海洋环境工程股份有限公司 | Ballast Management system cold water type oxide anode and preparation method |
| CN105836854A (en) * | 2016-05-23 | 2016-08-10 | 张家富 | Water treatment device with wide application, water treatment electrode and manufacturing method for water treatment electrode |
| CN108002390B (en) * | 2017-11-30 | 2019-02-05 | 亚洲硅业（青海）有限公司 | A kind of electrode for reduction furnace and its coating production |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN1962471A (en) * | 2006-11-28 | 2007-05-16 | 北京科技大学 | Method for electrolyzing organic waste water using iridium tantalum stannum oxide coating titanium electrode |
| CN1995464A (en) * | 2006-11-28 | 2007-07-11 | 北京科技大学 | Nanocrystalline iridium series oxide coating electrode preparation method |
| US7566389B2 (en) * | 2003-10-08 | 2009-07-28 | Akzo Nobel N.V. | Electrode |
| CN101565833A (en) * | 2009-05-23 | 2009-10-28 | 中国船舶重工集团公司第七二五研究所 | Positive and negative alternate electrolysis-resistance metal oxide electrode |
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| DE102009035546A1 (en) * | 2009-07-31 | 2011-02-03 | Bayer Materialscience Ag | Electrode and electrode coating |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| US7566389B2 (en) * | 2003-10-08 | 2009-07-28 | Akzo Nobel N.V. | Electrode |
| CN1962471A (en) * | 2006-11-28 | 2007-05-16 | 北京科技大学 | Method for electrolyzing organic waste water using iridium tantalum stannum oxide coating titanium electrode |
| CN1995464A (en) * | 2006-11-28 | 2007-07-11 | 北京科技大学 | Nanocrystalline iridium series oxide coating electrode preparation method |
| CN101565833A (en) * | 2009-05-23 | 2009-10-28 | 中国船舶重工集团公司第七二五研究所 | Positive and negative alternate electrolysis-resistance metal oxide electrode |
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Address after: Zhongshan East Road, Baixia District of Nanjing city in Jiangsu province 210002 silk No. 472 building 4 floor Patentee after: Jiangsu Meite forestry special alloy Limited by Share Ltd Address before: Zhongshan East Road, Baixia District of Nanjing city in Jiangsu province 210002 silk No. 472 building 4 floor Patentee before: Metalink Special Alloys Corporation |