Modified hard carbon negative electrode coated with organic acid complexed transition metal particles and preparation method of modified hard carbon negative electrode

Abstract

The invention belongs to the technical field of sodium ion battery materials, and particularly relates to a modified hard carbon negative electrode coated with organic acid complexed transition metal particles and a preparation method of the modified hard carbon negative electrode. According to the method, firstly, organic acid is used for complexing transition metal ions, then rich carboxyl of the organic acid is used for crosslinking with hydroxyl on the surface of hard carbon, and C = O (carbonyl) bonds are accurately and uniformly implanted into the surface of HC. The carbonyl group can provide sodium ion adsorption / deintercalation active sites, the transition metal ions can significantly improve the overall electronic conductivity of the material, and the complexing coating layer can improve the structural stability of the hard carbon material. After organic acid complexation transition metal ions are coated, the electrochemical performance of the hard carbon material is obviously optimized, the coulombic efficiency is improved by 16%, the first-cycle charging specific capacity under 0.1 C is improved from 237.18 mAh.g <-1 > to 398.70 mAh.g <-1 >, the specific capacity of 299 mAh.g <-1 > is provided under the large multiplying power of 5C (the contrast ratio is only 35 mAh.g <-1 >), and the cycling stability is greatly enhanced.

Description

Technical Field

[0001] This invention belongs to the field of sodium-ion battery materials technology, specifically relating to a modified hard carbon anode coated with organic acid complexed transition metal particles and its preparation method. Background Technology

[0002] With the rapid development of technology, human demand for energy is growing rapidly. Traditional fossil fuels are unsustainable, making the search for green and efficient renewable energy sources crucial. Electrochemical energy storage rechargeable batteries can efficiently store and convert green and sustainable energy sources such as wind, solar, tidal, and geothermal energy, offering advantages such as long cycle life, minimal environmental impact, and low maintenance costs. Among these, sodium-ion batteries are considered one of the most promising energy storage battery technologies due to their abundant raw material reserves, low cost, environmental friendliness, and excellent low-temperature performance.

[0003] Unlike lithium-ion batteries which use graphite anodes, sodium-ion batteries commonly employ hard carbon (HC) as the anode material. Hard carbon possesses high sodium storage capacity and good rate performance; however, its low initial coulombic efficiency (ICE), poor cycle stability, and varying compatibility with different electrolytes severely limit its large-scale practical application. Numerous studies have shown that simply optimizing the intrinsic structure of HC (e.g., heteroatom doping or microstructure modulation) is far from sufficient to improve the aforementioned electrochemical performance of HC anodes. Therefore, how to more effectively improve the electrochemical performance of HC anodes has become a pressing technical problem to be solved in this field. Summary of the Invention

[0004] To address the aforementioned issues, this application improves the electrochemical performance of the HC anode by constructing a stable solid electrolyte interface (SEI) to regulate the interfacial chemical structure between the HC anode and the electrolyte. First, organic acids are used to complex transition metal ions. Then, the abundant carboxyl groups of the organic acid are cross-linked with the hydroxyl groups on the hard carbon surface, accurately and uniformly implanting C=O (carbonyl) bonds onto the HC surface. The carbonyl groups provide active sites for sodium ion adsorption / deintercalation, while the transition metal ions significantly improve the overall electronic conductivity of the material. Simultaneously, the complexation coating layer enhances the structural stability of the hard carbon material. After the organic acid complexation and transition metal ion coating, the electrochemical performance of the hard carbon material is significantly optimized: the coulombic efficiency increases by 16%, and the first-week charge specific capacity at 0.1C increases from 237.18 mAh·g⁻¹. -1 Increased to 398.70mAh·g -1 It provides 299mAh·g at 5C high-rate charging. -1 The specific capacity (comparative example is only 35 mAh·g) -1 The cycle stability is greatly enhanced.

[0005] To achieve the above objectives, the first technical solution of this application discloses a method for preparing a modified hard carbon anode coated with organic acid-complexed transition metal particles, comprising:

[0006] S1. A mixture is obtained by mixing hard carbon materials, organic acids, and organic compounds of transition metal elements, and then adjusting the pH.

[0007] S1. The mixture is dehydrated and dried into powder, then washed and dried to obtain a modified hard carbon anode coated with organic acid complexed transition metal particles.

[0008] Furthermore, the hard carbon material mentioned in S1 is a biomass hard carbon material.

[0009] Furthermore, the organic acid S1 includes one or more of tannic acid, gallic acid, citric acid, and hydroxycinnamic acid.

[0010] Furthermore, the organometallic compounds of transition metal elements mentioned in S1 include one or more of nickel acetate, cobalt acetate, manganese acetate, copper sulfate, and nickel sulfate.

[0011] Furthermore, the mass ratio of the hard carbon material to the organic acid is 15:(1-4); the mass ratio of the organic acid to the organic compound of the transition metal element is 1:(1-3).

[0012] Furthermore, the pH adjustment range described in S1 is 5-11.

[0013] Furthermore, the dehydration reaction temperature described in S2 is 120℃-170℃, and the reaction time is 8-10h.

[0014] Furthermore, the modified hard carbon anode coated with organic acid complexed transition metal particles obtained according to the above preparation method and its application in sodium-ion batteries.

[0015] The second technical solution of this application discloses a sodium-ion battery, which includes a modified hard carbon anode coated with the above-mentioned organic acid complexed transition metal particles.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] (1) In the preparation method of this invention, organic acid and transition metal ions are complexed under hydrothermal conditions. Simultaneously, the complex reacts with the carboxyl / hydroxyl groups on the surface of the hard carbon material to undergo dehydration, further achieving in-situ polymerization on the surface of the hard carbon material, accurately and uniformly implanting C=O (carbonyl) bonds onto the HC surface. These C=O (carbonyl) bonds provide sodium storage active sites. The specific capacity of the coated and modified hard carbon material for sodium storage is increased by 68% compared to the uncoated and modified hard carbon material (the first-week charging specific capacity at 0.1C is increased from 237.18 mAh·g). -1 Increased to 398.70mAh·g-1 ).

[0018] (2) This invention achieves uniform coating of transition metal ions on the surface of hard carbon materials by first hydrothermally complexing transition metal ions with organic matter and then polymerizing them together with hard carbon materials in situ. After coating the hard carbon surface with transition metal ions, the overall electronic conductivity of the material can be significantly improved, the internal resistance of the electrode can be reduced, and active sites for sodium ion adsorption / deintercalation can be provided. At the same time, the hydrothermal complexation product of transition metal ions and organic matter is insoluble in water, and the complexation product can be used in aqueous systems and the mature aqueous binder of hard carbon anode can be used for subsequent coin cell assembly. The initial coulombic efficiency of the coated and modified hard carbon anode is 16% higher than that of the uncoated hard carbon anode, and the specific capacity at 5C high rate is 35 mAh·g -1 Increased to 299mAh·g -1 The cycle stability is significantly improved.

[0019] (3) The intermediate product of hydrothermal complexation of transition metal ions and organic matter prepared by the present invention can provide capacity. During the discharge process, electrons are transferred from HC to the unsaturated C=C bond of the complex of organic acid and transition metal ions, which then triggers chain growth and induces the complex to further polymerize to form a polymer film, thereby achieving surface reconstruction and improving the SEI film of hard carbon material. This makes the specific capacity of the synthesized hard carbon coated material far exceed the theoretical specific capacity of hard carbon and has better rate performance. Attached Figure Description

[0020] Figure 1 This is a detailed X-ray photoelectron spectroscopy (XPS) spectrum of Ni 2p in HC@NiTA from Example 1.

[0021] Figure 2 This is a transmission electron microscope (TEM) image of HC@NiTA in Example 1.

[0022] Figure 3 The image shows the Raman spectrum of HC@NiTA in Example 1.

[0023] Figure 4 The results show the 0.1C cycle performance of the sodium-ion battery assembled using HC@NiTA as the negative electrode in Example 1.

[0024] Figure 5 The results show the rate performance test results of the sodium-ion battery assembled using HC@NiTA as the negative electrode in Example 1.

[0025] Figure 6 The results show the 1C rate cycle performance of the sodium-ion battery assembled using HC@NiTA as the negative electrode in Example 1.

[0026] Figure 7 This is a comparative transmission electron microscope (TEM) image.

[0027] Figure 8 This is a comparative Raman diagram.

[0028] Figure 9 The results show the 0.1C cycle performance of a sodium-ion battery assembled with the negative electrode as a comparative example.

[0029] Figure 10 The results show the rate performance test results of the sodium-ion battery assembled with the negative electrode as a comparative example. Detailed Implementation

[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0031] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of this application. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

[0032] Unless otherwise specified, the technical terms in this specification have the same meaning as those generally understood by those skilled in the art; however, in case of any conflict, the definitions in this specification shall prevail.

[0033] The first embodiment of this application discloses a method for preparing a modified hard carbon anode coated with organic acid-complexed transition metal particles, comprising:

[0034] S1. A mixture is obtained by mixing hard carbon materials, organic acids, and organic compounds of transition metal elements, and then adjusting the pH.

[0035] S1. The mixture is dehydrated and dried into powder, then centrifuged and dried to obtain a modified hard carbon anode coated with organic acid complexed transition metal particles.

[0036] Wherein, the hard carbon material mentioned in S1 is a biomass hard carbon material. The biomass hard carbon material is made by burning precursors such as rice husks, coconut shells, bamboo, and starch, and its surface is rich in carboxyl and hydroxyl functional groups; the organic acid includes one or more of tannic acid, gallic acid, citric acid, and hydroxycinnamic acid; the transition metal element organometallic compound mentioned in S1 includes one or more of nickel acetate, cobalt acetate, manganese acetate, copper sulfate, and nickel sulfate.

[0037] The mass ratio of the hard carbon material to the organic acid is 15:(1-4); the mass ratio of the organic acid to the organic compound of the transition metal element is 1:(1-3).

[0038] In this embodiment, the solvent for the mixed hard carbon material, organic acid and transition metal element organic compound mentioned in S1 is preferably deionized water. In order to achieve a thorough mixing, the mixing temperature can preferably be 20-50℃ and stirred for 2-4 hours.

[0039] In this embodiment, the pH adjustment mentioned in S1 is an alkaline regulator, such as sodium hydroxide, and the pH adjustment range is 5-11.

[0040] In this embodiment, the dehydration reaction is preferably carried out in a hydrothermal reactor at a reaction temperature of 120℃-170℃ for 8-10 hours. After the dehydration reaction, the reaction product is dried into powder at a drying temperature of 80-100℃.

[0041] In a further embodiment, in order to improve the purity of the powder, the obtained powder can be washed and dried. The washing is preferably done by washing with distilled water and anhydrous ethanol more than twice and then centrifuging. After washing, the powder is dried to obtain a modified hard carbon anode coated with organic acid complexed transition metal particles.

[0042] The modified hard carbon anode coated with organic acid complexed transition metal particles obtained by the above preparation method is rich in C=O (carbonyl) groups that can provide active sites for sodium ion adsorption / deintercalation and transition metal ions that can improve conductivity, which can improve the structural stability of hard carbon materials.

[0043] The technical effects of the present application's technical solution will be described in detail below through specific embodiments.

[0044] The instruments and operations used in the tests involved in the following embodiments are as follows:

[0045] X-ray diffraction (XRD) test: Instrument model UltimaIV-185, manufactured by Rigaku Corporation, Japan;

[0046] Scanning electron microscope (SEM) test: Instrument model S-4800, manufactured by Hitachi, Japan;

[0047] X-ray photoelectron spectroscopy (XPS) test: Instrument model: manufactured by Shimadzu Corporation, Japan;

[0048] AC impedance testing: Electrochemical workstation, China, test frequency range 0.1Hz-0.1MHz;

[0049] Battery cycle performance testing: CT2001A Land battery testing system, manufactured by Wuhan Landian Electronics Co., Ltd.

[0050] Assembly of CR2032 button cell: Modified hard carbon negative electrode material, conductive carbon black (SuperP), and binder were weighed and ground in a mass ratio of 7:2:1, then a suitable amount of water was added and ground to form a slurry. This slurry was then evenly coated onto copper foil using a scraper and dried in an oven for 12 hours, followed by drying in a vacuum oven at 120°C for 3 hours. The dried electrode sheets were cut into pieces using a cutting machine and used as negative electrode sheets. The counter electrode was a sodium metal sheet. Electrolyte was added, and a glass fiber separator was used. The CR2032 button cell was assembled in an argon glove box (water < 0.01 ppm, oxygen < 0.01 ppm).

[0051] Example 1: Preparation of modified hard carbon anode (HC@NiTA-1) coated with organic acid-complexed transition metal particles.

[0052] (1) Weigh 3g of hard carbon sample, 0.4g of tannic acid, 0.2g of nickel acetate and 50ml of distilled water into a small beaker, and stir with a magnetic stirrer for 10 minutes at room temperature and 500r / min.

[0053] (2) Weigh about 0.05g of sodium hydroxide block and put it into the small beaker mentioned above. Adjust the pH to neutral and then set the temperature of the magnetic stirrer to 40℃ and stir at 500r / min for 2h.

[0054] (3) Place the stirred solution in a hydrothermal reactor, seal it, and place it in an oven. React at 140°C for 8 hours. Then open the hydrothermal reactor and dry the liquid inside at 100°C to obtain powder.

[0055] (4) The powder was washed with distilled water and centrifuged twice, and washed with anhydrous ethanol and centrifuged twice. The centrifugation speed was 800 r / min. The sediment was removed and dried at 80°C to obtain HC@NiTA-1 material.

[0056] Example 2: Preparation of modified hard carbon anode (HC@NiTA-2) coated with organic acid complexed transition metal particles.

[0057] (1) Weigh 3g of hard carbon sample, 0.6g of tannic acid, 0.2g of nickel acetate and 50ml of distilled water into a small beaker, and stir with a magnetic stirrer for 10 minutes at room temperature and 500r / min.

[0058] (2) Weigh about 0.05g of sodium hydroxide block and put it into the small beaker mentioned above. Adjust the pH to neutral, and then set the temperature of the magnetic stirrer to 40℃ and stir at 500r / min for 2h.

[0059] (3) Place the stirred solution in a hydrothermal reactor, seal it, and place it in an oven. React at 140°C for 8 hours. Then open the hydrothermal reactor and dry the liquid inside at 100°C to obtain powder.

[0060] (4) The powder was washed with distilled water and centrifuged twice, and washed with anhydrous ethanol and centrifuged twice. The centrifugation speed was 800 r / min. The sediment was removed and dried at 80°C to obtain HC@NiTA-2 material.

[0061] Example 3: Preparation of modified hard carbon anode (HC@NiTA-3) coated with organic acid-complexed transition metal particles.

[0062] (1) Weigh 3g of hard carbon sample, 0.3g of gallic acid, 0.2g of nickel acetate and 50ml of distilled water into a small beaker, and stir with a magnetic stirrer for 10 minutes at room temperature and 500r / min to dissolve.

[0063] (2) Weigh about 0.05g of sodium hydroxide block and put it into the small beaker mentioned above. Adjust the pH to neutral and then set the temperature of the magnetic stirrer to 40℃ and stir at 500r / min for 2h.

[0064] (3) Place the stirred solution in a hydrothermal reactor, seal it, and place it in an oven. React at 140°C for 8 hours. Then open the hydrothermal reactor and dry the liquid inside at 100°C to obtain powder.

[0065] (4) The powder was washed with distilled water and centrifuged twice, and washed with anhydrous ethanol and centrifuged twice. The centrifugation speed was 800 r / min. The sediment was removed and dried at 80°C to obtain HC@NiTA-3 material.

[0066] Example 4: Preparation of modified hard carbon anode (HC@CoTA) coated with organic acid-complexed transition metal particles.

[0067] (1) Weigh 3g of hard carbon sample, 0.4g of tannic acid, 0.15g of cobalt acetate and 50ml of distilled water into a small beaker, and stir with a magnetic stirrer for 10 minutes at room temperature and 500r / min to dissolve.

[0068] (2) Weigh about 0.05g of sodium hydroxide block and put it into the small beaker mentioned above. Adjust the pH to neutral and then set the temperature of the magnetic stirrer to 40℃ and stir at 500r / min for 2h.

[0069] (3) Place the stirred solution in a hydrothermal reactor, seal it, and place it in an oven. React at 140°C for 8 hours. Then open the hydrothermal reactor and dry the liquid inside at 100°C to obtain powder.

[0070] (4) The powder was washed with distilled water and centrifuged twice, and washed with anhydrous ethanol and centrifuged twice. The centrifugation speed was 800 r / min. The sediment was removed and dried at 80°C to obtain HC@CoTA material.

[0071] Example 5: Preparation of modified hard carbon anode (HC@CoGA-1) coated with organic acid-complexed transition metal particles.

[0072] (1) Weigh 3g of hard carbon sample, 0.3g of gallic acid, 0.15g of cobalt acetate and 50ml of distilled water into a small beaker, and stir with a magnetic stirrer at room temperature and 500r / min for 10 minutes to dissolve.

[0073] (2) Weigh about 0.05g of sodium hydroxide block and put it into the small beaker mentioned above. Adjust the pH to neutral and then set the temperature of the magnetic stirrer to 40℃ and stir at 500r / min for 2h.

[0074] (3) Place the stirred solution in a hydrothermal reactor, seal it, and place it in an oven. React at 140°C for 8 hours. Then open the hydrothermal reactor and dry the liquid inside at 100°C to obtain powder.

[0075] (4) The powder was washed with distilled water and centrifuged twice, and washed with anhydrous ethanol and centrifuged twice. The centrifugation speed was 800 r / min. The sediment was removed and dried at 80°C to obtain HC@CoGA-1 material.

[0076] Example 6: Preparation of modified hard carbon anode (HC@CoGA-2) coated with organic acid-complexed transition metal particles.

[0077] (1) Weigh 3g of hard carbon sample, 0.45g of gallic acid, 0.15g of cobalt acetate and 50ml of distilled water into a small beaker, and stir with a magnetic stirrer for 10 minutes at room temperature and 500r / min to dissolve.

[0078] (2) Weigh about 0.05g of sodium hydroxide block and put it into the small beaker mentioned above. Adjust the pH to neutral and then set the temperature of the magnetic stirrer to 40℃ and stir at 500r / min for 2h.

[0079] (3) Place the stirred solution in a hydrothermal reactor, seal it, and place it in an oven. React at 140°C for 8 hours. Then open the hydrothermal reactor and dry the liquid inside at 100°C to obtain powder.

[0080] (4) The powder was washed with distilled water and centrifuged twice, and washed with anhydrous ethanol and centrifuged twice. The centrifugation speed was 800 r / min. The sediment was removed and dried at 80°C to obtain HC@CoGA-2 material.

[0081] Comparative Example 1: Preparation of Hard Carbon Anode

[0082] The preparation method is the same as in Example 1, except that the comparative example contains only 3g of hard carbon sample and does not contain 0.4g of tannic acid or 0.2g of nickel acetate.

[0083] The samples prepared in Examples 1-6 and the comparative examples were used as the negative electrode materials of the batteries. The batteries were assembled according to the assembly method of CR2032 button batteries, and the 0.1C cycle performance, rate performance and 1C rate cycle performance were tested.

[0084] Through investigation, the optimal coating complexation parameters were determined to be hard carbon: tannic acid: nickel acetate = 15:2:1. The electrochemical performance and characterization under these parameters are shown in Example 1 of the attached figure.

[0085] Ni 2p (ni 2p) in Example 1 3 / 2 and ni 2p 1 / 2 The XPS fine-resolution image, TEM image, and Raman image are attached. Figure 1 Appendix Figure 2 and attached Figure 3 The fine XPS pattern of Ni 2p shows that nickel on the surface of the Example 1 sample exists as divalent nickel ions, consistent with the valence state of nickel when tannic acid complexes with nickel. The TEM image shows a distinct coating layer on the surface of the Example 1 sample, and the coating layer thickness is relatively uniform. The Raman image shows that the Example 1 sample I... D / I G Smaller, lower I D / I G The sample in Example 1 showed fewer side reactions with the electrolyte and fewer surface defects.

[0086] The 0.1C cycle performance, rate performance, and 1C rate cycle performance results of Example 1 are further detailed in Appendix I. Figure 4 To be continued Figure 6 Expanding on the middle. (Attached) Figure 4 In the first week, the battery achieved a specific charge capacity of 398.7 mAh·g under 0.1C conditions. -1Furthermore, the coulombic efficiency in the first week was 16% higher than the control, because the tannic acid complex with nickel provided sodium storage energy, and the complex coating improved structural stability. Figure 5 In the middle, at a high rate of 5C, the battery capacity can be maintained at 299mAh·g. -1 The above; Appendix Figure 6 In Example 1, the battery can stably cycle for more than 600 cycles at a 1C rate while maintaining a capacity of 280 mAh·g. -1 The above demonstrates excellent rate-cycle stability;

[0087] like Figure 7 , Figure 8 TEM images and Raman spectroscopy images of the uncompared hard carbon anode material show that the hard carbon anode material prepared in the comparative example has no coating layer, and the Raman spectroscopy image is not shown in Figure I. D / I G Larger than Example 1. Figure 9 and Figure 10 Uncompared 0.1C cycle performance and rate performance graphs, in which... Figure 9 It can be seen that the hard carbon anode material prepared in the comparative proportion suffers from cycling instability and low capacity (250 mAh·g). -1 The following are the questions. Figure 10 It can be seen that as the tests are conducted at different magnifications, the comparative model exhibits serious problems such as extremely unstable cycles and inability to fully utilize its capacity.

[0088] The above embodiments are merely preferred embodiments of the present invention, and the scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing a modified hard carbon negative electrode coated with organic acid complexed transition metal particles, characterized in that, include: S1. A mixture is obtained by mixing hard carbon materials, organic acids, and organic compounds of transition metal elements, and then adjusting the pH. S1. The mixture is dehydrated and dried into powder, then washed and dried to obtain a modified hard carbon anode coated with organic acid complexed transition metal particles.

2. The preparation method according to claim 1, characterized in that, The hard carbon material mentioned in S1 is a biomass hard carbon material.

3. The preparation method according to claim 1, characterized in that, The organic acids mentioned in S1 include one or more of tannic acid, gallic acid, citric acid, and hydroxycinnamic acid.

4. The method of claim 1, wherein the step of forming the first and second layers is performed by a process selected from the group consisting of: sputtering, evaporation, and chemical vapor deposition. The transition metal organometallic compound S1 includes one or more of nickel acetate, cobalt acetate, manganese acetate, copper sulfate, and nickel sulfate.

5. The method of claim 1, wherein the step of forming the first and second layers is performed by a process selected from the group consisting of: sputtering, evaporation, and chemical vapor deposition. The mass ratio of the hard carbon material to the organic acid is 15:(1-4); the mass ratio of the organic acid to the organic compound of the transition metal element is 1:(1-3).

6. The method of claim 1, wherein the step of forming the first and second layers is performed by a process selected from the group consisting of: sputtering, evaporation, and chemical vapor deposition. The pH adjustment range described in S1 is 5-11.

7. The method of claim 1, wherein the step of forming the first and second layers is performed by a process selected from the group consisting of: sputtering, evaporation, and chemical vapor deposition. The dehydration reaction temperature of S2 is 120℃-170℃, and the reaction time is 8-10h.

8. The modified hard carbon anode coated with organic acid complexed transition metal particles obtained by any of the preparation methods described in claims 1-7.

9. The application of the modified hard carbon anode coated with organic acid complexed transition metal particles according to claim 8 in sodium-ion batteries.

10. A sodium-ion battery, characterized in that, The modified hard carbon anode, including the organic acid complexed transition metal particle coated as described in claim 7.

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