A carbon carrier with a bacterial morphology prepared by coating bacteria with TEOS and a preparation method and application thereof

Abstract

The application provides a carbon carrier with a bacterial morphology prepared by coating bacteria with TEOS and a preparation method and application thereof, and the preparation process of the carbon carrier is as follows: bacteria are subjected to a series of operations such as conventional subculture, fixation, dehydration, freeze-drying and the like, then the bacterial dry powder is mixed with TEOS at a proper ratio and subjected to hydrolysis coating, after reaction for a certain time, the excess TEOS is washed away by washing the mixture three times according to the method of alternately adding water and ethanol, and after freeze-drying, the obtained dry powder is put into a porcelain boat and pyrolyzed under a protective atmosphere to obtain the carbon carrier with the bacterial morphology. The method for preparing the carbon carrier with the bacterial morphology by coating bacteria with TEOS is simple in process, adjustable in morphology and friendly to the environment, the carrier has a certain metal loading capacity, and the prepared Pt / C catalyst has good electrochemical application potential.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fuel cell catalyst materials, in particular to a bacterial morphology carbon carrier prepared by coating bacteria with TEOS and a preparation method and application thereof. BACKGROUND

[0002] Traditional carbon-based catalyst carriers, including activated carbon, carbon nanotubes, graphene, etc., perform well in high specific surface area and electrical conductivity. However, these traditional carriers have obvious shortcomings: their synthesis process depends on high-temperature cracking or chemical vapor deposition technology, making it difficult to accurately control the pore structure, and the types of surface functional groups are single, which limits the effective exposure of the catalytic active sites and the loading efficiency of the catalyst. In addition, traditional carbon-based carriers lack biomimetic structure design, which to some extent restricts their synergistic effect with catalysts. In recent years, the preparation of porous carbon materials by biological template method has brought new breakthroughs to this field. This method significantly improves the diversity of carrier structure and functionalization potential by imitating natural biological structures, such as bacterial cellulose, opening up a new direction for the development of carbon-based catalyst carriers.

[0003] Bacteria are uniform in size (0.5-5 μm), and bacteria themselves are mainly composed of carbon (C), hydrogen (H), oxygen (O), nitrogen (N), phosphorus (P), sulfur (S) and trace amounts of other elements. The rich nitrogen (N) and phosphorus (P) content provides an adequate source of heteroatoms for doped carbon networks, while minimizing the doping level of other pollutants. The bacterial cell interior has a variety of highly porous cell structures, which makes the carbon material derived therefrom expected to achieve a large surface area and potentially controllable pore structure. Therefore, bacteria become an ideal candidate for biological templates, showing great potential in preparing high-performance carbon-based catalyst carriers. However, in the process of preparing carbon materials by existing biological template method, there are problems such as uncontrolled morphology, easy collapse of structure and complex process. SUMMARY

[0004] In view of this, the first object of the present application is to provide a bacterial morphology carbon carrier preparation method which is simple in process, adjustable in morphology and environmentally friendly.

[0005] In order to prepare efficient ORR catalysts, low-cost carbon carriers need to be developed, and the second object of the present application is to prepare carbon carriers with loading capacity, which requires the carbon carrier to have a certain metal loading capacity to facilitate the preparation of ORR catalysts later.

[0006] To experimentally achieve the above technical purposes, the present application provides a method for preparing a carbon carrier with a bacterial morphology by coating bacteria with tetraethyl orthosilicate (TEOS), which selects a single gram-positive bacterium as a raw material, first passes the bacteria through a conventional culture method for subculture and expansion, dehydrates and dries, collects the dried bacterial powder, mixes the dried bacterial powder with TEOS according to a certain ratio for hydrolysis coating, washes the mixture with ethanol and water alternately for 3 times, and dries the mixture. Finally, the dried sample is carbonized, the obtained carbon material is treated with HF to remove TEOS, and finally a gram-positive bacterial carbon carrier material with a bacterial morphology is obtained.

[0007] The gram-positive bacteria can be gram-positive or gram-negative, and the type of bacteria is not strictly required, and has a certain universality. Since the carrier constructed by the present application has a morphology highly consistent with the morphology of the bacteria itself, based on this characteristic, in order to maximize the advantages of the carrier and ensure the performance stability and consistency of the final product, it is recommended to preferentially select a single pure bacterium. In the current biotechnology field, the fermentation technology of bacteria has become mature and continuously improved, and with the aid of this advanced technical means, a variety of bacterial resources can be easily obtained, thereby providing a solid guarantee for the supply of raw materials, and ensuring the relative abundance of the source of raw materials. In addition, different types of bacteria have rich chemical composition and a wide variety of elements. This enables the preparation of carbon carrier materials using gram-positive bacteria as a derivative raw material to fully utilize the chemical properties of the bacteria themselves, laying a solid and deep material foundation for the innovative research and development and expanded application of carbon carrier materials, and expanding the application potential and development space of carbon carrier materials in multiple fields.

[0008] In one specific embodiment of the present application, Shewanella oneidensis (MR-1) is selected for constructing the carrier. Shewanella oneidensis MR-1) for constructing the carrier.

[0009] The technical solution of the present application is as follows:

[0010] A method for preparing a carbon carrier with a bacterial morphology by coating bacteria with TEOS, comprising the following steps: hydrolysis coating of gram-positive bacterial powder and tetraethyl orthosilicate under alkaline or acidic conditions, drying to obtain hydrolysis coating dry powder, carbonization under inert conditions, and drying to obtain the carbon carrier with a bacterial morphology;

[0011] The volume-to-mass ratio of tetraethyl orthosilicate to gram-positive bacterial powder is 1 mL: 0.1 g to 0.4 g.

[0012] Further, the gram-positive bacterial powder is obtained by activation culture, expansion culture, fixation, dehydration, and drying.

[0013] The expanding culture comprises subculturing the bacterial liquid through 2-4 generations;

[0014] The fixing comprises collecting the precipitated bacterial bodies after centrifugation of the bacterial liquid obtained through the expanding culture, and fixing the bacterial bodies at 2-6 DEG C through an organic solvent; the organic solvent comprises glutaraldehyde, and the mass concentration of the glutaraldehyde is 2-4 %;

[0015] The dehydrating comprises gradient dehydrating through ethanol solutions with volume concentrations of 30 %-100 %; the gradient dehydrating comprises sequentially dehydrating through ethanol solutions with volume concentrations of 30 %-35 %, 50 %-55 %, 70 %-75 % and 95 %-100 %; after the gradient dehydrating through the ethanol solutions, the dehydrating further comprises dehydrating through ethanol and tert-butanol; and the time for each dehydrating is 8-15 min.

[0016] Further, the gram-negative bacteria comprise Shewanella oleracea (S. oleracea) and Geobacter sulfurreducens (G. sulfurreducens); Shewanella oneidensis MR-1).

[0017] Further, the alkaline condition is pH 9-11, and the acidic condition is pH 2-3;

[0018] The hydrolysis coating is achieved by adjusting the pH of a tetraethyl orthosilicate solution, hydrolyzing the solution, mixing the hydrolyzed solution with dry gram-negative bacteria powder, and then hydrolyzing the mixture; or the hydrolysis coating is achieved by adjusting the pH of a hydrolysis solution, adding dry gram-negative bacteria powder into the hydrolysis solution, ultrasonic dispersing the mixture, and then adding tetraethyl orthosilicate into the mixture for hydrolysis coating.

[0019] The tetraethyl orthosilicate solution is obtained by mixing tetraethyl orthosilicate, anhydrous ethanol and water at volume ratios of 1-2:3-4:5-6.

[0020] The hydrolysis solution is obtained by mixing anhydrous ethanol and water at volume ratios of 3-4:5-6.

[0021] Further, the hydrolysis coating is achieved at 30-40 DEG C for 4-8 h, and stirring is further performed during the hydrolysis at a rate of 100-300 rpm.

[0022] Further, the carbonization is achieved at 500-1000 DEG C for 2-4 h, and the temperature is raised at a rate of 3-5 DEG C / min during the carbonization.

[0023] Further, after the carbonization, the carbon is further cleaned with a hydrofluoric acid solution for 4-8 h to remove silicon contained in the carbon, and the mass concentration of the hydrofluoric acid solution is 8 %-15 %; or the silicon contained in the carbon is removed through heating of sodium hydroxide.

[0024] In one aspect, the application further provides a carbon carrier with a bacterial morphology prepared through the preparation method.

[0025] In another aspect, the present application also provides a use of the carbon carrier with bacterial morphology in loading metal.

[0026] Further, the application also provides a use of the carbon carrier with bacterial morphology in preparing a metal catalyst in a fuel cell.

[0027] Compared with the prior art, the present application has the following beneficial effects:

[0028] The present application uses gram-negative bacteria Shewanella oneidensis (MR-1) as raw material, and through a series of operations such as expansion culture, fixation, dehydration and freeze-drying, a bacterial dry powder is obtained, which is hydrolyzed and coated with TEOS according to a ratio, and then washed, dried and carbonized in an inert gas atmosphere to obtain a carbon carrier material with the morphology of Shewanella oneidensis itself. Shewanella oneidensis The carrier has a certain metal loading capacity, and the method for preparing the carbon carrier with bacterial morphology by coating bacteria with TEOS provided by the present application is simple in process, adjustable in morphology and environmentally friendly.

[0029] The carbon carrier material prepared by the present application has the morphology of bacteria itself, and compared with a Pt / C catalyst prepared by a carbon carrier without TEOS hydrolysis coating, the Pt / C catalyst prepared by the carbon carrier with bacterial morphology provided by the present application has better electrocatalytic activity and better electrochemical application potential. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 The process flowchart of the present application is shown in the figure;

[0031] Figure 2 , Figure 3 The SEM image of the bacterial dry powder prepared in Example 1 is shown in the figure;

[0032] Figure 4 , Figure 5 The SEM image of the carrier material obtained by carbonizing the bacteria coated with TEOS prepared in Example 1 is shown in the figure;

[0033] Figure 6 , Figure 7 , Figure 8 , Figure 9 The SEM image of the carrier material obtained by directly carbonizing the bacteria prepared in Comparative Example 1 is shown in the figure;

[0034] Figure 10 The CV graph of the three-electrode test of the Pt-loaded carrier prepared is shown in the figure;

[0035] Figure 11 The LSV graph of the three-electrode test of the Pt-loaded carrier prepared is shown in the figure;

[0036] Figure 10 ,Figure 11 In the diagram, the horizontal axis represents potential (electric potential), and the vertical axis represents current density (current density). Detailed Implementation

[0037] To better understand the technical content of this invention, specific embodiments are provided below to further illustrate the invention.

[0038] Unless otherwise specified, the experimental methods used in the embodiments of this invention are all conventional methods.

[0039] Unless otherwise specified, all materials and reagents used in the embodiments of this invention are commercially available.

[0040] Lake Oneida Shewanella ( Shewanella oneidensis The MR-1 strain was purchased from the China Industrial Microbial Culture Collection Center (CICC). The received strain was activated by filling tubes with approximately 0.5 mL of liquid culture medium (TSB) according to the operating procedure to prepare the Shewanella Oneida culture.

[0041] Example 1 - Acidic Hydrolysis

[0042] The preparation steps of the carbon support with bacterial morphology are as follows:

[0043] (1) Take 3 mL of *Shewanella oneda* bacterial suspension and inoculate it into 30 mL of TSB (tryptone soybean broth) liquid medium, which is recorded as the first generation bacterial suspension. Subculture at a volume ratio of 1:10. After 10 h, subculture 30 mL of the first generation bacterial suspension into 300 mL of TSB medium, which is recorded as the second generation bacterial suspension. After 10 h, subculture 300 mL of the second generation bacterial suspension into 3000 mL of TSB medium, which is recorded as the third generation bacterial suspension. Culture conditions: 30℃, aerobic, 100-180 rpm shaker culture. After 10 h, collect the third generation bacterial suspension by centrifugation (6000 rpm, 10 min). Wash the collected bacteria three times with physiological saline to remove residual culture medium.

[0044] (2) The bacteria collected by centrifugation were fixed with 2.5% glutaraldehyde at 4°C for more than 4 hours or overnight.

[0045] (3) The fixed bacteria were washed three times with PBS to remove excess glutaraldehyde, and then subjected to gradient ethanol dehydration (30%, 50%, 70%, 100% once each, ethanol and tert-butanol 1:1 once, 10 min each time) to prepare tert-butanol bacterial suspension for pre-freezing.

[0046] (4) The pre-frozen bacterial suspension was placed in a vacuum freeze dryer and dried for more than 24 hours to obtain bacterial powder.

[0047] (5) Mix according to the volume ratio of TEOS: anhydrous ethanol: ultrapure water = 1:4:5, hydrolyze for 30 min after adjusting the pH value to 2-3, mix according to the ratio of TEOS: bacterial dry powder = 1 mL: 0.3 g, mix after adding bacterial dry powder, stir at 200 rpm and 35°C for 6 h, after hydrolysis and coating, wash with ethanol and water alternately for three times, vacuum freeze dry for more than 24 h, and obtain dry powder.

[0048] (6) Carbonize the dry powder at 800°C for 3 h under a nitrogen atmosphere (heating rate: 5°C / min), remove the silicon contained in the carbon by washing with 8-15% hydrofluoric acid (HF) for 4-8 h after carbonization is completed, and obtain the carbon carrier with bacterial morphology after drying.

[0049] Example 2 - Acidic hydrolysis

[0050] The preparation steps of the carbon carrier with bacterial morphology are as follows:

[0051] (1) Take 3 mL of Shewanella oneidensis bacterial solution and inoculate into 30 mL of TSB (tryptone soybean broth) liquid medium, and record it as first generation bacterial solution, and subculture according to the volume ratio of 1:10, 30 mL of first generation bacterial solution is subcultured into 300 mL of TSB medium after 10 h, and recorded as second generation bacterial solution, 300 mL of second generation bacterial solution is subcultured into 3000 mL of TSB medium after 10 h, and recorded as third generation bacterial solution, and the culture conditions are 30°C, aerobic, and 100-180 rpm shaking culture. After 10 h, centrifuge the third generation bacterial solution (6000 rpm, 10 min), and wash the collected bacteria with normal saline three times to remove the residual culture medium.

[0052] (2) Fix the centrifuged bacteria with 2.5% glutaraldehyde at 4°C for more than 4 h or overnight.

[0053] (3) Wash the fixed bacteria with PBS three times to remove excess glutaraldehyde, and then perform ethanol gradient dehydration (30%, 50%, 70%, 100% each time, ethanol and tert-butyl alcohol 1:1 once, each time for 10 min), and prepare a pre-frozen bacterial suspension.

[0054] (4) Place the pre-frozen bacterial suspension into a vacuum freeze dryer and dry for more than 24 h to obtain bacterial dry powder.

[0055] (5) After adjusting the pH value of the hydrolysis solution to 2-3, bacterial dry powder is added for ultrasonic treatment for 10 min to make the bacterial dry powder more uniformly dispersed, TEOS is added dropwise in a proportion of 1 mL:0.3 g of TEOS:bacterial dry powder, stirring is carried out at 200 rpm and 35°C for 6 h, the ratio of the hydrolysis solution is anhydrous ethanol:ultra-pure water=4:5, the hydrolysis solution is configured in a volume ratio of TEOS:anhydrous ethanol:ultra-pure water=1:4:5, after the completion of the hydrolysis coating, the ethanol and water are alternately washed for three times, vacuum freeze-drying is carried out for more than 24 h, and the dry powder is obtained.

[0056] (6) The dry powder is carbonized at 800°C for 3 h under a nitrogen atmosphere (the heating rate is 5°C / min), 8-15% HF washing is carried out for 4-8 h after the carbonization is completed, silicon contained in the carbon is removed, and a carbon carrier with a bacterial morphology is obtained after drying.

[0057] Example 3-alkaline hydrolysis

[0058] The difference between this example and Example 1 is that step (5) is alkaline hydrolysis, and TEOS is first hydrolyzed. The specific steps are as follows:

[0059] (1) 3 mL of Shewanella oneidensis bacterial solution is inoculated into 30 mL of TSB (tryptone soybean broth) liquid medium, which is recorded as first-generation bacterial solution, and is subcultured according to a volume ratio of 1:10, 30 mL of the first-generation bacterial solution is subcultured into 300 mL of TSB medium after 10 h, which is recorded as second-generation bacterial solution, 300 mL of the second-generation bacterial solution is subcultured into 3000 mL of medium after 10 h, which is recorded as third-generation bacterial solution, and the culture conditions are 30°C, aerobic, and 100-180 rpm shaking culture. The third-generation bacterial solution is centrifuged (6000 rpm, 10 min) after 10 h, and the collected bacteria are washed with normal saline for three times to remove the residual medium.

[0060] (2) The centrifuged bacteria are fixed with 2.5% glutaraldehyde at 4°C for more than 4 h or overnight.

[0061] (3) The fixed bacteria are washed with PBS for three times to remove excess glutaraldehyde, and then gradient dehydration with ethanol (30%, 50%, 70%, 100% each time, ethanol and tert-butyl alcohol 1:1 once, each time for 10 min) is carried out to prepare a tert-butyl alcohol bacterial suspension pre-freeze.

[0062] (4) The pre-frozen bacterial suspension is placed in a vacuum freeze dryer for drying for more than 24 h to obtain bacterial dry powder.

[0063] (5) Mixing according to the volume ratio of TEOS: anhydrous ethanol: ultrapure water = 1:4:5, hydrolyzing for 30 min after adjusting the pH value to 9-11, mixing according to the ratio of TEOS: bacterial dry powder = 1 mL: 0.3 g, stirring at 200 rpm and 35℃ for 6 h, after hydrolysis coating is completed, washing with ethanol and water alternately for three times, vacuum freeze-drying for more than 24 h, and obtaining the dry powder.

[0064] (6) Carbonizing the dry powder at 800℃ for 3 h under nitrogen atmosphere (heating rate: 5℃ / min), removing the silicon contained in the carbon by washing with 8-15% HF for 4-8 h after carbonization is completed, and obtaining the carbon carrier with bacterial morphology after drying.

[0065] Example 4 - Alkaline hydrolysis

[0066] The difference between this example and Example 2 is that step (5) is alkaline hydrolysis, and the bacteria are dispersed first. The specific steps are as follows:

[0067] (1) Take 3 mL of Shewanella oneidensis bacterial liquid and inoculate into 30 mL of TSB (tryptone soybean broth) liquid medium, and mark it as first generation bacterial liquid. Subculture according to the volume ratio of 1:10, and after 10 h, subculture 30 mL of first generation bacterial liquid into 300 mL of TSB medium, and mark it as second generation bacterial liquid. After 10 h, subculture 300 mL of second generation bacterial liquid into 3000 mL of TSB medium, and mark it as third generation bacterial liquid. The culture conditions are: 30℃, aerobic, 100-180 rpm shaking culture. After 10 h, centrifuge and collect the third generation bacterial liquid (6000 rpm, 10 min), and wash the collected bacteria with normal saline three times to remove the residual culture medium.

[0068] (2) Fix the centrifuged bacteria with 2.5% glutaraldehyde at 4℃ for more than 4 h or overnight.

[0069] (3) Wash the fixed bacteria with PBS three times to remove excess glutaraldehyde, and then perform ethanol gradient dehydration (30%, 50%, 70%, 100% each time, ethanol and tert-butyl alcohol 1:1 once, each time for 10 min) to prepare a tert-butyl alcohol bacterial suspension pre-freeze.

[0070] (4) Place the pre-frozen bacterial suspension into a vacuum freeze dryer and dry for more than 24 h to obtain a bacterial dry powder.

[0071] (5) After adjusting the pH value of the hydrolysis solution to 9-11, bacterial dry powder was added and ultrasonicated for 10 min to make the bacterial dry powder more uniformly dispersed. TEOS was added dropwise in a proportion of 1 mL:0.3 g of TEOS:bacterial dry powder, and stirring was performed at 200 rpm and 35°C for 6 h. The ratio of the hydrolysis solution was anhydrous ethanol:ultra-pure water=4:5, and the hydrolysis solution was prepared in a volume ratio of TEOS:anhydrous ethanol:ultra-pure water=1:4:5. After the completion of the hydrolysis coating, the ethanol and water were alternately washed three times, and vacuum freeze-drying was performed for more than 24 h to obtain a dry powder.

[0072] (6) The dry powder was carbonized at 800°C under a nitrogen atmosphere for 3 h (heating rate: 5°C / min), and after the completion of carbonization, 8-15% HF washing was performed for 4-8 h to remove silicon contained in the carbon, and a carbon carrier with a bacterial morphology was obtained after drying.

[0073] Comparative Example 1

[0074] The difference between this comparative example and Example 1 is that the bacterial dry powder does not undergo the TEOS hydrolysis coating step, and the details are as follows:

[0075] (1) 3 mL of Shewanella oneidensis bacterial solution was inoculated into 30 mL of TSB (tryptone soya broth) liquid medium, and was recorded as first generation bacterial solution. Subculture was performed at a volume ratio of 1:10, and after 10 h, 30 mL of the first generation bacterial solution was subcultured into 300 mL of TSB medium, and was recorded as second generation bacterial solution. After 10 h, 300 mL of the second generation bacterial solution was subcultured into 3000 mL of TSB medium, and was recorded as third generation bacterial solution. The culture conditions were 30°C, aerobic, and 100-180 rpm shaking culture.

[0076] (2) The centrifugally collected bacteria were fixed with 2.5% glutaraldehyde at 4°C for more than 4 h or overnight.

[0077] (3) The fixed bacteria were washed with PBS three times to remove excess glutaraldehyde, and then ethanol gradient dehydration was performed (30%, 50%, 70%, 100% each once, and ethanol and tert-butyl alcohol 1:1 once, each for 10 min), and a tert-butyl alcohol bacterial suspension pre-freeze was prepared.

[0078] (4) The pre-frozen bacterial suspension was placed in a vacuum freeze dryer and dried for more than 24 h to obtain bacterial dry powder.

[0079] (5) The bacterial dry powder was carbonized at 800°C under a nitrogen atmosphere for 3 h (heating rate: 5°C / min), and after the completion of carbonization, 8-15% HF washing was performed for 4-8 h to remove silicon contained in the carbon, and a carbon carrier was obtained after drying.

[0080] Example 1 - Pt / C catalyst

[0081] The Pt / C catalyst was prepared as follows:

[0082] Solution 1: carbon support: 0.1 g, H2O: 8.3 g, ethylene glycol: 12.36 g;

[0083] Solution 2: 50% H2PtCl4: 1.3297 mL - 5.32 mL (20% - 50%), 10%wt NaOH: 1.388 g, ethylene glycol: 3.952 g;

[0084] Solution 1, solution 2 were respectively ultrasonic for 5 min, mixed and ultrasonic for 30 min, uniform stirring for 30 min, 124℃ microwave for 10~20 s, then 0.5 mL nitric acid was added, after cooling, deionized water was added and stirred for 1 h, filtered, vacuum dried, to obtain the Pt / C catalyst.

[0085] The Pt / C catalyst was prepared by the above method using the carbon support with bacterial morphology prepared in Example 1 and the carbon support prepared in Comparative Example 1, respectively, and LSV / CV was tested by three electrode, electrode composition: working electrode was glassy carbon electrode, reference electrode was saturated calomel electrode, counter electrode was platinum wire, the prepared Pt / C catalyst was added dropwise on the working electrode to test CV / LSV curve, respectively.

[0086] The LSV / CV test results of the present application Figures 10-11 The carbon support with bacterial morphology prepared in Example 1 of the present application applied to the Pt / C catalyst, the electrocatalytic activity of the catalyst is better than that of the Pt / C catalyst prepared by the carbon support without TEOS hydrolysis coating.

[0087] The above only describes the preferred embodiments of the present application and is not intended to limit the present application, any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for preparing a carbon support with a bacterial morphology by coating bacteria with TEOS, characterized in that, The method comprises the following steps: The dry powder of the gram bacteria is hydrolytically coated with tetraethyl orthosilicate under alkaline or acidic conditions, dried to obtain a hydrolytically coated dry powder, and carbonized under inert conditions to obtain the carbon carrier with the bacterial morphology; The volume-mass ratio of the tetraethyl orthosilicate to the dry powder of the gram bacteria is 1 mL:0.1 g-0.4 g; The gram-negative bacteria is Shewanella odiaca Shewanella oneidensis MR-1; After the carbonization is completed, the carbon carrier is further cleaned with a hydrofluoric acid solution for 4-8 hours, and the mass concentration of the hydrofluoric acid solution is 8%-15%; or the carbon carrier is heated with sodium hydroxide.

2. The production method according to claim 1, characterized by, The dry powder of the gram bacteria is obtained through activation culture, expansion culture, fixation, dehydration, and drying. The expansion culture comprises subculturing the bacterial liquid through 2-4 generations. The fixation comprises centrifuging the bacterial liquid obtained through the expansion culture, collecting the precipitated bacterial bodies, and fixing the bacterial bodies at 2-6°C with an organic solvent; the organic solvent comprises glutaraldehyde, and the mass concentration of the glutaraldehyde is 2%-4%. The dehydration comprises gradient dehydration with ethanol solutions with a volume concentration of 30%-100%; the gradient dehydration comprises sequentially using ethanol solutions with a volume concentration of 30%-35%, 50%-55%, 70%-75%, and 95%-100%; after the gradient dehydration with the ethanol solutions is completed, the carbon carrier is further dehydrated with ethanol and tert-butanol; and the time for each dehydration is 8-15 minutes.

3. The preparation method according to claim 1, characterized in that, The alkaline condition is a pH value of 9-11, and the acidic condition is a pH value of 2-3. The hydrolytic coating is performed in the following manner: the tetraethyl orthosilicate solution is adjusted in pH value, then hydrolyzed, and then mixed with the dry powder of the gram bacteria to perform hydrolytic coating; or the hydrolysis liquid is adjusted in pH value, then added with the dry powder of the gram bacteria to perform ultrasonic dispersion, and then added with the tetraethyl orthosilicate to perform hydrolytic coating. The tetraethyl orthosilicate solution is obtained by mixing tetraethyl orthosilicate, anhydrous ethanol, and water in a volume ratio of 1-2:3-4:5-6. The hydrolysis liquid is obtained by mixing anhydrous ethanol and water in a volume ratio of 3-4:5-6.

4. The method of claim 1, wherein, The hydrolytic coating is performed at 30-40°C for 4-8 hours; and stirring is further performed during the hydrolysis, and the stirring rate is 100-300 rpm.

5. The preparation method according to claim 1, characterized in that, The carbonization is performed at 500-1000°C for 2-4 hours, and the temperature rising rate during the carbonization is 3-5°C / min. 6.A carbon carrier with the bacterial morphology, which is prepared by the preparation method in any one of claims 1-5. 7.The carbon carrier with the bacterial morphology in claim 6 is applied to loading of metal.

8. Use according to claim 7, characterized in that, The carbon carrier with the bacterial morphology is applied to preparation of a metal catalyst in a fuel cell.

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