JP2007269545A - Carbon structure and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a carbon structure having a high interlayer density and a high bulk density by maintaining the interlayer distance wider than that of graphite and a manufacturing method thereof.
The carbon structure of the present invention removes part of oxygen covalently bonded by firing of graphite oxide, and has an XRD (X-ray diffraction) diffraction pattern peak in the range of 19 ° to 26 °. In addition, the density according to the He method is 1.4 g / cm ³ or more and the volume resistivity is 1 Ω · cm or less. In the above carbon structure, the constituent components are at least carbon and oxygen, and the proportion of oxygen is about 1 to 25 wt%.
[Selection figure] None

Description

  The present invention relates to a novel carbon structure having a regular structure with an interlayer distance wider than that of graphite and a method for producing the same. In this specification, H, Ar, N, He, and the like are element symbols.

  Recently, the development of clean battery technology and fuel cell components to be installed in hybrid vehicles and electric vehicles has been accelerated due to the promotion of environmental problems and energy saving measures. For example, a high-capacity and high-power material is desired for a lithium ion battery, and further improvement in energy density is desired for a capacitor. And for lithium-ion batteries, improvements to higher capacity and higher output are being promoted, and the use of graphite materials with good crystallinity can support higher capacity, but the higher output point It is inferior and has many problems. Further, when non-graphitizable carbon is used, high output can be obtained, but it is difficult to adapt to high capacity batteries.

The carbon negative electrode materials that have been put to practical use are roughly classified into three types: graphitizable carbon (soft carbon), graphite, and non-graphitizable carbon (hard carbon) as described in the following document 1. The Among these, graphitizable carbon is carbon that develops a graphite crystal when subjected to a heat treatment at 2000 ° C. or higher, and easily shifts to a graphite structure. The average crystallite size is _{L c} is 5nm _{approximately, d 002} is 0.34 nm, crystallite number is several tens of the order of several sheets. A density of about 1.8 to 2.0 g / cm ³ is often used. On the other hand, graphite is widely used as a negative electrode material for lithium ion secondary batteries. In addition to natural graphite, artificial graphite obtained by heat-treating graphitizable carbon at a high temperature of 2000 ° C. or higher, such as MCMB, mesophase / pitch-based carbon fiber. Etc. are used. Graphite crystallization has progressed, the size _{L c} of the crystallites is not less 100nm or more, in crystallite number 300 or more _{sheets, d 002} is 0.3354 nm, density of the 2.1~2.25g / cm ³ high. Further, non-graphitizable carbon is almost amorphous and does not reach a graphite structure even when subjected to high temperature treatment. The crystallite is small and there are only a few laminated structures. d ₀₀₂ is as wide as 0.37 nm or more, and the density is 1.5 to 1.7 g / cm ³ , which is lower than that of graphite.

As for the characteristics of each material, in the case of a graphite negative electrode with advanced crystallinity, if a high-boiling propylene carbonate (PC) solvent is used as the electrolyte, PC decomposition is preferentially performed during lithium doping, so PC is used. Can not. However, it can be used for easily graphitizable carbon and non-graphitizable carbon having no developed graphite structure. On the other hand, from the viewpoint of capacity, graphite is a material with high crystallinity and high density, and its charge capacity per volume is excellent. However, regarding rapid charge / discharge characteristics and cycle characteristics in a region where the current density is high, non-graphitizable carbon having a low crystallinity and a wide d ₀₀₂ is excellent. This is presumably because the resistance when Li ions are doped is small and the expansion during doping / dedoping is small. In addition, for gas storage materials such as hydrogen storage materials, it has been suggested by simulation that the gas storage capacity can be dramatically increased by the formation of regular layers wider than graphite. A material having high properties and high bulk density has not yet been put into practical use.
Issued by Maruzen Co., Ltd., “Battery Handbook-Third Edition”, pages 272-277

  By the way, as a carbon structure having a large discharge capacity and a large output, a material having a high density and a high doping amount of Li ions and a high crystallinity is required. In addition, a high-boiling solvent such as PC can be used, and a carbon structure with good cycle characteristics requires a material of about 0.38 nm in which the expansion during Li ion doping / dedoping is small and the interlayer distance is wider than that of graphite. Conceivable. Further, as a gas storage material such as a hydrogen storage material, it is necessary to form a regular space between layers.

  Therefore, the present invention uses graphite oxide in which oxygen is covalently bonded between the graphite layers, and removes oxygen while maintaining the regularity between the layers, so that the interlayer distance is maintained wider than that of graphite, and the density and bulk by the He method are increased. An object is to provide a high-density carbon structure and a method for producing the same.

The inventors first tried to use graphite oxide whose interlayer distance regularly spreads to about 0.67 nm for the purpose of creating a carbon-based material having a regular interlayer wider than that of graphite. Then, firing conditions and the like were examined in more detail with the aim of removing oxygen and aligning the graphite oxide layer to about 0.38 nm and preventing regularity and density reduction between layers. From the test, oxygen in graphite oxide is rapidly released as H ₂ O, CO ₂ , and CO at about 270 ° C. by firing, and the release of gas is further promoted by the reaction heat at that time. Explosive expansion and miniaturization progressed, and it was confirmed that it became amorphous.

  Therefore, the present inventors have been able to remove oxygen while maintaining the regularity between layers, or as a result of intensive research from that point, as a result of using a reducing gas with good heat conductivity that can instantly release the heat of the sample. It was discovered that the reduction of regularity between layers can be suppressed by suppressing the accumulation of reaction heat in the sample, preventing the sudden release of gas, and suppressing the expansion, by firing. It was.

That is, the carbon structure of claim 1 removes some of the covalently bonded oxygen by firing (under controlled and controlled conditions to suppress expansion) of graphite oxide, and the XRD (X-ray diffraction) diffraction pattern The peak is in the range of 19 ° to 26 °, the density by He method is 1.4 g / cm ³ or more, and the volume resistivity is 1 Ω · cm or less.

From the test results, the above carbon structure is composed of at least carbon and oxygen, and the proportion of oxygen is about 1 to 25 wt% (Claim 2), and the composed components are at least carbon and oxygen. The carbon is about 87 wt% or more, the oxygen is about 1 to 9 wt%, and has regular layers of 0.34 to 0.40 nm (Claim 3), Raman spectroscopy The R value, which is the ratio between the D band and G band of the spectrum, is 0.3 to 0.8 (Claim 4), the specific surface area is 20 m ² / g or less, and the bulk density is 0.1 g / cm ³ or more. (Claim 5), these requirements are also important.

The manufacturing method of claim 6 is the above-described carbon structure identified from the manufacturing method. The first process for synthesizing graphite oxide in which oxygen is bonded between graphite layers, and oxygen in graphite oxide by firing. The method for producing a carbonaceous structure according to claim 1, wherein the method comprises a second process of removing carbon. In the above manufacturing method, the second process is firing in an atmosphere of He gas or H ₂ gas (Claim 7), and the heating is performed at a heating rate slower than 10 ° C./min up to the reduction temperature. It is also important that the first process is a process in which fuming nitric acid and potassium chlorate are added to and mixed with crystalline graphite (claim 9).

  As described above, the carbon structure of the present invention has a small expansion during doping / de-doping of Li ions, maintains an interlayer distance wider than that of graphite, and has a high density and a high bulk density. It is useful for increasing the capacity and output of the negative electrode material for batteries, and is a useful structure for hydrogen storage. In addition, since the production method of the present invention can be carried out by selecting graphite oxide and controlling the setting of firing conditions, the carbon structure of the present invention can be mass-produced at low cost while suppressing the production cost.

First, the carbon structure of the present invention uses graphite oxide with expanded graphite layers as a raw material, and removes some of the covalently bonded oxygen by firing with suppressed expansion. The peak of the XRD diffraction pattern starts from 19 °. It is a structure having a novel regularity in a range of 26 °, a density by He method of 1.4 g / cm ³ or more, and a volume resistivity value of 1 Ω · cm or less.

Here, the graphite oxide prepared by the Brodie method is an intercalation compound in which oxygen is covalently bonded between about 36 wt% and 38 wt% between graphite layers, and the interlayer distance is expanded to about 0.67 nm. When this graphite oxide is baked, the covalently bonded oxygen is suddenly released as H ₂ O, CO ₂ , CO at about 270 ° C., resulting in finer particles due to rapid expansion and disruption of the regular structure. appear. Therefore, the present inventors have made it possible to release an oxygen compound while maintaining the regular structure of graphite oxide by examining the firing conditions. In other words, in the carbon structure of the present invention, the suppression of the expansion is important from the viewpoint that it is important to minimize the temperature rise in the sample due to the reaction heat generated at the time of sudden gas release at about 270 ° C. This has been achieved through repeated studies and improvements in firing conditions.

It is said that heat conduction generally moves from higher to lower temperature, but in this case, molecules with higher kinetic energy collide with adjacent lower kinetic energy molecules. This occurs when part of the energy of molecules with high kinetic energy on the colliding side moves toward lower molecules. Therefore, also in the firing of graphite oxide, it is considered that the influence of the atmosphere gas during firing is large in order to prevent the accumulation of reaction heat (in the graphite oxide). From this point, as a result of the examination, in the firing in vacuum, air, Ar gas, or N ₂ , sample expansion occurs rapidly with gas generation, and the 2θ peak due to particle refinement and XRD is observed. It changed to broad and the disappearance of regular structure occurred.

However, it has been found that in firing in He gas, there is almost no expansion when gas is released, and a regular structure by XRD after firing can be confirmed. In addition, the effect of suppressing expansion was also observed in firing in an H2 gas atmosphere. For example, focusing on the thermal conductivity, the above phenomenon is 0.0241 W / m · K for air, 0.0015 W / m · K for Ar, and 0.0242 W / m · K for N ₂ . On the other hand, He is 0.1415 W / m · K, and H ₂ is 0.1684 W / m · K, both of which show considerably higher thermal conductivity than the former.

Thus, the present inventors have confirmed that it is an important requirement to use He gas or H ₂ gas having at least a considerably high thermal conductivity in the operation of removing oxygen from graphite oxide by calcination. The production method of the present invention is specified from the requirements, and uses graphite oxide having an interlayer distance wider than that of graphite, and heat-fires it in an atmosphere of He gas or H ₂ gas as a reducing gas, and oxygen in the graphite oxide. Try to get rid of some of the.

Further, the present inventors have found that there is a clear correlation between the oxygen content, the XRD peak position, and the volume resistivity value. That is, in the above carbon structure, when the oxygen content exceeds about 25 wt%, a large peak of graphite oxide is recognized at around 13 to 14 °, and the volume resistivity is about 10 to 10 ⁸ Ω · cm. . However, when the oxygen content is in the range of about 22 wt% to 17 wt%, the peak intensity of graphite oxide near 2θ = 13 to 14 ° decreases, and a new peak appears at 2θ = 19.5 ° to 21 °. The volume resistivity in this region varies from 0.1 to 10 Ω · cm. Furthermore, when the oxygen content is about 17 wt% or less, the 13 to 14 ° graphite oxide peak disappears and the new peak intensity around 22 ° increases. At this time, the volume resistivity is 0.1 Ω · cm or less. On the other hand, the present inventors show that the hydrogen storage capacity becomes maximum in a region where a peak of graphite oxide near 2θ = 13 to 14 ° and a new peak of 2θ = 19.5 ° to 21 ° appear. I have confirmed.

  That is, in the carbon structure of the present invention, the constituent component is composed of at least carbon and oxygen, and the proportion of oxygen contained is about 1 to 25 wt%, or the constituent component is composed of at least carbon and oxygen. Further, carbon is about 87 wt% or more, and the oxygen ratio is about 1 wt% to 9 wt%. In particular, in the latter configuration, a carbon structure having an XRD peak of 22 ° to 26 ° (regular 3.40 to 4.00 ° interlayer) can also be used as a lithium ion battery material. These carbon structures have a wider interlayer than graphite, and have improved crystallinity than non-graphitizable carbon (hard carbon), and are effective for application to lithium ion battery materials with high output.

Further, in the carbon structure of the present invention, the R value (R = 0.3 to 0.8) of the Raman spectrum is large, graphitization is not progressing, and the specific surface area is as small as 20 m ² / g or less. It is also characterized by a bulk density as high as 0.1 g / cm ³ or more. These are not limited to application to lithium ion battery materials, but are useful as applications to gas storage materials having regular layers.

  In the following examples, in order to create a carbon-based material having a regular interlayer wider than that of graphite, graphite oxide having an interlayer distance regularly spread to about 0.67 nm was used. It is an example when oxygen in the inside is removed.

(1. Preparation of Graphite Oxide) In Tables 1 and 2, the graphite oxides of Samples 1 to 11 were prepared by the Brodie method using natural graphite (flaky graphite) having an average particle diameter of 8 μm and 16 μm as follows. First, 8 g of natural graphite was put into 150 ml of fuming nitric acid, and 64.4 g of potassium chlorate was further added to react for 3 hours. The reaction temperature was kept at 55 ° C. After completion of the reaction, graphite oxide was obtained by dilution, filtration and drying.

(Reduction treatment) For each of the prepared graphite oxides, in order to partially remove oxygen in the graphite oxide, 200 ° C to 1000 ° C in N ₂ gas, He gas, H ₂ gas, and vacuum atmosphere (10 -3 Torr). The baking temperature was changed to 0 ° C. and heating was performed for 1 h. The heating was performed up to a predetermined reduction temperature under conditions of 2 ° C./min to 10 ° C./min. In Tables 1 and 2, Sample 1 is graphite oxide (comparative example) that is not fired. Samples 2 to 7 are the same in that the atmosphere is He gas and the heating rate is 5 ° C./min. Sample 2 was heated at a firing temperature of 200 ° C. for 1 h (Comparative Example), Sample 3 was heated at a firing temperature of 250 ° C. for 1 h (Example), and Sample 4 was heated at a firing temperature of 270 ° C. for 1 h ( Example), sample 5 was heated for 1 h at a firing temperature of 300 ° C. (Example), sample 6 was heated for 1 h at a firing temperature of 500 ° C. (Example), and sample 7 was heated for 1 h at a firing temperature of 1000 ° C. (Comparative example). Sample 8 was heated in H2 gas and heated at a rate of 2 ° C./min and calcined at 400 ° C. for 1 h (Example). Sample 9 was heated in H ₂ gas and heated at a rate of 10 ° C./min. Heated at 400 ° C. for 1 h (Comparative Example), Sample 10 was N ₂ gas with a heating rate of 5 ° C./min, heated at a baking temperature of 400 ° C. for 1 h (Comparative Example), and Sample 11 was in a vacuum atmosphere Among them, the heating rate was 2 ° C./min and the baking temperature was 400 ° C. for 1 h (Comparative Example).

(2. Physical properties of sample) Samples 1 to 11 processed under the above conditions were subjected to powder X-ray diffraction analysis, elemental analysis, specific surface area measurement, powder resistance measurement, density measurement by He method, and Raman spectroscopic analysis as follows. It was done like that.

(Powder X-ray diffraction) In this diffraction, MXP18VAHF manufactured by Mac Science Co., Ltd. was used as an X-ray diffraction apparatus utilizing an automatic recording method (diffractometer) using a counter (counter tube). In the measurement, the voltage and current applied to the X-ray tube were 40 kV and 150 mA, and CuKα was used as the incident X-ray. The X-ray powder pattern of each sample was measured, and 2θ on the (002) plane and interlayer distance d ₀₀₂ on the (002) plane were measured.

(Elemental analysis) An elemental analyzer (Perkin Elmer 2004) was used for analysis of C, H, and N as constituent components. The analysis of O was performed using Vario EL manufactured by Elemental.

(Specific surface area) The specific surface area of each of the samples 1 to 11 was measured by using a nitrogen adsorption method, and the BET equation by Brunauer-Emmett-Teller was used for analysis (standard: ISO 9277).

(Powder Resistance) Using a powder resistance meter PD-51 manufactured by Mitsubishi Chemical Corporation, the powder resistance (volume resistivity) at the time of pressurization was measured at 650 kg / cm ² . FIG. 3 is a graph showing the relationship between the volume resistivity and the oxygen content.

(Measurement of Density by He Method) In this measurement, as schematically shown in FIG. 1, the He equilibrium pressure density was measured as follows using a measuring apparatus including the pressure vessels 1 and 2. First, approximately 1 g of the measurement sample is accurately put into the pressure vessel 2. Next, after evacuating the pressure vessels 1 and 2, about 0.2 MPa of He is put into the vessel 2 and the pressure P _0.2 is accurately measured. Further, with the valve 1 on the pressure vessel 2 side closed, He with a pressure of 0.8 MPa is put into the pressure vessel 1 and the pressure P _0.8 is accurately measured. Further, in the closed state of the valve 2 provided on the upstream side piping of the pressure vessel 2, to measure the He equilibrium pressure P _E valve 1 and the pressure vessel 1 to open the valve 3 and the pressure vessel 2. Then, He equilibrium compaction of the sample determine the V _s based on the equation 1 below.

(Formula 1)
[(P _0.8 · V ₂ ) / T _0.8 ] + [(P _0.2 · (V ₁ −V _s ) / T _0.2 ) =
[(P _E · V ₂ ) / T _E ] + [P _E · (V ₁ −V _s ) / T _E ]

And the density in He method is calculated | required from sample weight W / sample volume Vs. Here, the volumes V ₁ and V ₂ of the reaction vessel are measured in advance. Moreover, although the temperature ( _T0.8 , _T0.2 , _TE ) in the pressure vessel in each pressure condition was set to 30 degreeC, the measured value was used for the measurement of the density by He method.

As analysis method of the surface structure (Raman spectroscopy) carbon materials, by Raman spectroscopy (NRS-2100 of Renishow Co.) at an intensity ratio of G-band (1580 cm ^-1 vicinity) and D-band (1360 cm around ^-1) A certain R value (I ₁₃₆₀ / I ₁₅₈₀ ) was determined and evaluated. Ar laser light was used for the measurement.

(Measurement of hydrogen storage amount) For samples 1 to 7, the hydrogen storage amount and hydrogen release amount were measured by a test method according to JIS 7201 and 7203. In this measurement, each sample was precisely weighed, placed in a sample tube and evacuated, and then the hydrogen pressure was increased to 12 MPa, and the hydrogen storage amount [mass%] was measured by the volume method. Next, the temperature was returned to room temperature, and the hydrogen release amount was confirmed.

(Table 1)

(Table 2)

(3. Evaluation) Each of the samples 1 to 6 in Table 1 uses flaky graphite having a particle size of 8 μm, adjusts graphite oxide to the Brodie method, sample 1 is not fired, and samples 2 to 6 are in a He atmosphere. This is an example of reduction and firing. That is, sample 1 has the characteristics of graphite oxide. Oxygen is 35.6 wt% covalently bonded between the graphite layers, the XRD 2θ has a peak at 13.38 °, and the layer is expanded to 0.66 nm (black theorem). In Tables 1 and 2, in the lower determination column, “x” indicates a comparative example, and “◯” indicates an example.

Samples 2 to 7 are carbon structures in which a part of the covalently bonded oxygen is removed by firing with suppressed thermal expansion using He gas having good thermal conductivity. It can be seen that with the removal of oxygen, the 2θ peak of XRD moves from the low angle to the high angle side as shown in FIG. 2, the interlayer approaches the graphite, and the volume resistivity decreases. In particular, the carbon structures of samples 3 to 6 having a peak at 2θ of 19 ° to 23 ° can reduce the volume resistivity to 1 Ω · cm or less, and the density by He method is 1.5 g / cm ³ or more. The density required for the battery material in the range is maintained, and the interlayer distance of the (002) plane calculated from 2θ is also 0.39 nm to 0.45 nm, and the regular interlayer is maintained.

  Further, there is a close relationship between the amount of oxygen in the interlayer and the distance between the layers. In particular, the carbon structure of Sample 6 has a carbon specific structure of 87 wt%, an oxygen ratio of 7 wt%, and a volume resistivity of 0.015Ω.・ As low as cm, the XRD peak is 22.72 ° (having a regular interlayer of 0.39 nm), and is suitable as a battery material.

Here, the carbon structure of Sample 7 is an example of firing at −1000 ° C. in a He atmosphere. However, 2θ is 26.5 °, and the interlayer distance is 0.336 nm which is almost equal to the graphite interlayer. is there. At this time, the oxygen content is less than 1 wt%, and oxygen of 1 wt% or more is required for expansion between layers.
As described above, a novel carbon structure having an interlayer distance (0.34 nm to 0.40 nm) close to that of hard carbon, which is a negative electrode material that places importance on output characteristics, by changing the reduction temperature condition and controlling the ratio of oxygen. Can be adjusted.

  Further, as apparent from Sample 1, the R value, which is the ratio of the D band to the G band in the Raman spectrum of the graphite oxide used, is 0.729, which is higher than that of general graphite (R value is about 0.1). It shows a high value. That is, it is surmised that the graphite oxide used has a decrease in crystal size and crystallinity on the surface. In addition, the R values of Samples 2 to 6 obtained by reducing the graphite oxide to remove oxygen show a high R value without being much lower than that before the reduction. Thus, it can be seen that the carbon structure of each sample obtained by removing oxygen by reduction using graphite oxide exhibits a high R value even when the interlayer is close to graphite.

The carbon structures of Samples 8 to 11 are obtained by comparing differences in the firing atmosphere. The carbon structures of Samples 8 and 9 are examples in which the temperature raising time up to 400 ° C. is set to 2 ° C./min and 10 ° C./min in firing in an H ₂ gas atmosphere. H ₂ gas is a gas having high thermal conductivity, but by changing the temperature rise temperature to 10 ° C./min as in sample 9, the decomposition gas containing oxygen generated at around 270 ° C. and the reaction heat Due to heat storage, rapid gas release and sample expansion occur, resulting in a significant decrease in bulk density. In this respect, it was confirmed from the sample 8 that when the temperature rising rate was set to 2 ° C./min, the heat of reaction heat was smoothly radiated and explosive gas generation could be prevented. In addition, from the carbon structures of the sample 10 fired in the N ₂ gas atmosphere and the sample 11 fired in the vacuum atmosphere, heat release during the reaction is insufficient, and explosive gas release and expansion of the structure are caused. It was confirmed that it cannot be suppressed. Although not mentioned in the examples, a carbon structure using the same graphite oxide as above and calcined in an air atmosphere or an Ar gas atmosphere has a tendency similar to that of the sample 10, that is, heat release during the reaction is insufficient. It was not possible to suppress explosive gas release and sample expansion.

From the above, it is important to use at least a high thermal conductivity He gas or H ₂ gas as a reducing gas used for firing graphite oxide to suppress expansion and maintain a regular structure. I understood. In addition, the carbon structures of Samples 2 to 8 reduced with He gas or H ₂ gas have a specific surface area of 20 m ² / g or less and a bulk density of 0.1 g / cm ³ or more. It has suitable characteristics.

  Further, although the hydrogen storage amount was not included in the table, the graphite oxide of sample 1 was 0.04 wt%, whereas the carbon structure of sample 4 was 0.27 wt% at the maximum. Both carbon structures of Samples 6 and 7 were 0.09 wt%. In other words, it has been confirmed that the hydrogen storage capacity has a maximum value in a region where a peak of graphite oxide near 2θ = 13 to 14 ° and a new peak of 2θ = 19.5 ° to 21 ° can be confirmed.

  The carbon structure of the present invention has conductivity close to that of graphite, and can be applied to conductive materials, capacitors, battery materials such as lithium ion batteries, hydrogen storage materials, and the like.

It is a reference schematic diagram for demonstrating the measuring method of He equilibrium pressure density. It is a diffraction diagram which shows the XRD pattern of a graphite oxide baking product (samples 1-7). It is a graph which shows the relationship between oxygen content and volume specific resistance.

Explanation of symbols

1 and 2 are pressure vessels

Claims (9)

A part of oxygen covalently bonded by removing graphite oxide is removed, and the peak of the diffraction pattern in the XRD (X-ray diffraction) measurement is in the range of at least 19 ° to 26 °, and the He method A carbon structure having a measured density at 1.4 g / cm ³ or more and a volume resistivity of 1 Ω · cm or less   The carbon structure of claim 1, wherein the constituents comprise at least carbon and oxygen, and the proportion of oxygen is about 1 to 25 wt%.   The component comprises at least carbon and oxygen, wherein carbon is in a proportion of about 87 wt% or more, oxygen is in a proportion of about 1 to 9 wt%, and has regular layers of 0.34 to 0.40 nm. 1 carbon structure   The carbon structure according to claim 1, wherein the R value, which is the ratio of the D band to the G band in the Raman spectrum, is 0.3 to 0.8. The carbon structure according to claim 1, wherein the specific surface area is 20 m ² / g or less and the bulk density is 0.1 g / cm ³ or more.   6. The carbon according to claim 1, comprising: a first process for synthesizing graphite oxide in which oxygen is bonded between graphite layers; and a second process for removing oxygen in the graphite oxide by firing. A method for producing a textured structure. The method for producing a carbonaceous structure according to claim 6, wherein the second process is firing in an atmosphere of He gas or H ₂ gas.   The said heating is a manufacturing method of the carbonaceous structure of Claim 7 performed at the temperature increase rate slower than 10 degrees C / min to reduction temperature. 9. The method for producing a carbonaceous structure according to claim 6, wherein the first process is a process in which fuming nitric acid and potassium chlorate are added to and mixed with crystalline graphite.

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