Boron-doped carbon-based material and preparation method thereof

Abstract

The invention relates to the field of carbon-based composite materials, in particular to a boron-doped carbon-based material and a preparation method thereof.The boron-doped carbon-based material is prepared from, by mass, 80-95% of microcrystalline wax, 5-10% of modifier, 5-10% of calcium sulfate, 5-10% of nano carbon powder, 5-10% of ferric oxide, 5-10% of zinc oxide, 5-10% of titanium dioxide and 5-10% of trimethyl borate; 1-5% of a modifier; 1-3% of nano carbon powder; 1-3% of calcium sulfate; 1 to 3% of ferric oxide; 1-3% of zinc oxide; 1-3% of titanium dioxide; in the melting process of the microcrystalline wax, a melting method is adopted, firstly, heat preservation is performed at a relatively high melting temperature (150-200 DEG C) to improve the fluidity of a microcrystalline wax melt, so that the aim of fully and uniformly mixing all the component raw materials is achieved, and a consistent environment is created for lattice ion substitution in subsequent heat treatment.

Description

Technical Field

[0001] The present invention relates to the field of carbon-based composite materials, and in particular to a boron-doped carbon-based material and a preparation method thereof. Background Art

[0002] Carbon-based materials are widely used in energy storage, environmental protection, electronic devices, catalysis and other fields due to their excellent physical and chemical properties, such as high conductivity, good mechanical strength, and wide chemical stability. Driven by the development of modern science and technology and industry, people have higher and higher requirements on the functions and performance of carbon-based materials. Among many water treatment technologies, carbon-based materials based on modified paraffin wax and trace elements are widely used in the restoration and reconstruction of aquatic ecosystems by providing carbon sources to microorganisms. Traditional carbon-based material formulas usually include components such as microcrystalline wax, modifiers, calcium sulfate, nano-carbon powder, ferric oxide, zinc oxide, and titanium dioxide. These materials can form biowax products after high-temperature reactions. However, there are some shortcomings in the existing technology. For example, the carbon (C) atoms in some reaction processes fail to completely react chemically with other components, resulting in unstable performance and shortened service life of the final product.

[0003] In order to solve the above problems, many researchers have tried to improve the performance of carbon-based materials by adding other chemicals. In recent years, boron (B), as an important doping element, has shown significant effects in improving the performance of carbon-based materials due to its unique electronic structure and chemical properties. B doping can change the electronic structure of carbon-based materials, increase conductivity and chemical reactivity. Patent CN114530601A discloses a preparation method of boron-doped porous materials and their application in potassium ion batteries. Under the doping of B, the transmission efficiency of ions and electrons during charging and discharging can be accelerated, and the electrochemical performance of the battery can be improved. Patent CN108840679B discloses a preparation method of crystalline boron-doped carbon materials. By doping with B, a material with high surface activity, few defects and high conductivity can be obtained. Trimethyl borate (C3H9BO3), as a provider of B, not only has excellent antibacterial and antioxidant properties, but also can participate in complex chemical reactions under high temperature conditions. Therefore, introducing trimethyl borate into the preparation process of carbon-based materials may significantly improve the performance and stability of the product.

[0004] These examples show that the performance of the material can be significantly improved by introducing B into the material. In the preparation process of carbon-based biowax, trimethyl borate is added under high temperature conditions, so that the active boron atoms penetrate into the surface of the carbon material, diffuse into the interior of the carbon material, and penetrate into the interlayer of the carbon material crystal to replace its lattice, completing the replacement of C atoms by B atoms. By changing the chemical composition and structure of the carbon material surface, the stability of the carbon-based biowax is improved. Summary of the invention

[0005] In order to solve the problems of the prior art, the present invention provides a boron-doped carbon-based material, the components of which include microcrystalline wax, a modifier, calcium sulfate, nano-carbon powder, ferric oxide, zinc oxide, titanium dioxide and trimethyl borate, and the mass percentage content is as follows: Microcrystalline wax: 80-95%; Modifier: 1-5%; Nano carbon powder: 1-3%; Calcium sulfate: 1-3%; Ferrous oxide: 1-3%; Zinc oxide: 1-3%; Titanium dioxide: 1-3%; Trimethyl borate: 1-3%.

[0006] A method for preparing a boron-doped carbon-based material comprises the following steps: Step 1, adding all components of the boron-doped carbon-based material as claimed in claim 1 into a reaction kettle for reaction; Step 2: After the reaction is completed, the reactor is cooled down naturally to 70-80°C; Step 3: Casting in a mold to quickly obtain a biowax product under circulating refrigeration of cooling water.

[0007] Furthermore, in step 1, the reactor is heated to 150-200° C. and kept at this temperature for 360 min.

[0008] Compared with the prior art, the present invention has the following beneficial effects: a boron-doped carbon-based material and a preparation method thereof include a melting process of microcrystalline wax, a heat treatment process and a biowax molding process. In the melting process of microcrystalline wax, a melting method is adopted, firstly, the temperature is kept at a relatively high melting temperature (150-200 ° C) to improve the fluidity of the microcrystalline wax melt, thereby achieving the purpose of fully and uniformly mixing the raw materials of each component, and creating a consistent environment for lattice ion substitution in subsequent heat treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 This is an XRD pattern of a boron-doped carbon-based material of the present invention; Figure 2 It is a thermal analysis spectrum of a boron-doped carbon-based material of the present invention. DETAILED DESCRIPTION

[0010] In order to further understand the features, technical means, specific objectives and functions of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. Example

[0011] 85 g of microcrystalline wax, 5 g of modifier, 3 g of nano-carbon powder, 1.4 g of CaSO4, 1.2 g of Fe2O3, 1.5 g of ZnO, 1.3 g of TiO2 and 1.6 g of C3H9BO3 were weighed respectively, the above components were mixed evenly and placed in a reactor, kept at 150 °C for 360 minutes, then the melting temperature was reduced to 70 °C, the molten liquid was poured into a mold in a water cooling system, and naturally cooled to obtain a carbon-based material biowax; The XRD test results of the carbon-based biowax are as follows: Figure 1 As shown in the figure, it can be seen that the diffraction peak of the microcrystalline phase completely corresponds to the JCPDS standard card crystal phase, but the 2θ angle has a right shift of 0.2°, indicating that although the lattice structure in the microcrystal has not changed, the lattice ions may have changed, indicating that part of the C in the carbon-based material microcrystal is replaced by B.

[0012] The thermal analysis spectrum of the carbon-based material is as follows Figure 2 As shown in the figure, the melting point peak of the B-doped sample shifted 2 °C to the right, and the phase change enthalpy decreased by 17.6 J / g. This indicates that the introduction of the B element changes the lattice structure, making it more stable and reducing the energy required for the phase change process. Example 1

[0013] 88 g of microcrystalline wax, 3 g of modifier, 2 g of nano-carbon powder, 1.6 g of CaSO4, 1.5 g of Fe2O3, 1.5 g of ZnO, 1.2 g of TiO2 and 1.2 g of C3H9BO3 were weighed respectively, the above components were mixed evenly and placed in a reactor, kept at 180 °C for 360 min, then the melting temperature was reduced to 70 °C, the molten liquid was poured into a mold in a water cooling system, and naturally cooled to obtain a carbon-based material biowax; The XRD test results show that the diffraction peak of the microcrystal phase completely corresponds to the JCPDS standard card crystal phase, but the 2θ angle has a rightward shift of 0.35°, indicating that although the lattice structure of the microcrystal has not changed, the lattice ions may have changed, indicating that part of the C in the carbon-based material microcrystal is replaced by B.

[0014] Thermal analysis results show that the melting point peak of the B-doped sample shifted to the right by 5.6 °C, and the phase change enthalpy decreased by 28.8 J / g. This indicates that the introduction of the B element changes the lattice structure, making it more stable, and reduces the energy required for the phase change process. Example 2

[0015] 90 g of microcrystalline wax, 2 g of modifier, 1.5 g of nano-carbon powder, 1.0 g of CaSO4, 1.2 g of Fe2O3, 1.3 g of ZnO, 1.2 g of TiO2 and 1.8 g of C3H9BO3 were weighed respectively, the above components were evenly mixed and placed in a reactor, kept at 200 °C for 360 minutes, and then the melting temperature was reduced to 70 °C, and the molten liquid was poured into a mold in a water cooling system and naturally cooled to obtain a carbon-based material biowax; The XRD test results show that the diffraction peak of the microcrystal phase completely corresponds to the JCPDS standard card crystal phase, but the 2θ angle has a rightward shift of 0.52°, indicating that although the lattice structure of the microcrystal has not changed, the lattice ions may have changed, indicating that part of the C in the carbon-based material microcrystal is replaced by B.

[0016] Thermal analysis results show that the melting point peak of the B-doped sample shifted to the right by 10.5 °C, and the phase change enthalpy decreased by 55.1 J / g, indicating that the introduction of the B element changed the lattice structure, making it more stable, and reduced the energy required for the phase change process.

[0017] The above embodiments only express one or several implementation modes of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for those of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the attached claims.

Claims

1. A boron-doped carbon-based material, characterized in that: Its components include microcrystalline wax, modifier, calcium sulfate, nano carbon powder, ferric oxide, zinc oxide, titanium dioxide and trimethyl borate, and the mass percentage contents are as follows: Microcrystalline wax: 80-95%; Modifier: 1-5%; Nano carbon powder: 1-3%; Calcium sulfate: 1-3%; Ferrous oxide: 1-3%; Zinc oxide: 1-3%; Titanium dioxide: 1-3%; Trimethyl borate: 1-3%.

2. A method for preparing a boron-doped carbon-based material, characterized in that: The steps include: Step 1, adding all components of the boron-doped carbon-based material as claimed in claim 1 into a reaction kettle for reaction; Step 2: After the reaction is completed, the reactor is cooled down naturally to 70-80°C; Step 3: Casting in a mold to quickly obtain a biowax product under circulating refrigeration of cooling water.

3. The method for preparing a boron-doped carbon-based material according to claim 2, characterized in that: In step 1, the reactor is heated to 150-200°C and maintained at this temperature for 360 min.

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