CN115188949B - Preparation method of mesocarbon microbead-silicon carbon composite negative electrode material - Google Patents
Preparation method of mesocarbon microbead-silicon carbon composite negative electrode material Download PDFInfo
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Abstract
The invention discloses a preparation method of a mesocarbon microbead-silicon carbon composite negative electrode material, which comprises the following steps: the preparation method comprises the steps of placing medium-temperature asphalt in a reaction kettle for polymerization reaction to obtain polymerized asphalt, settling and centrifuging to obtain mesocarbon microbeads, modifying the mesocarbon microbeads by a plasma technology to obtain modified mesocarbon microbeads, preparing a silane coupling agent organic solvent containing organic lithium salt, depositing silicon salt on the surfaces of the modified mesocarbon microbeads by an electrochemical deposition method, washing and carbonizing to obtain the modified mesocarbon microbeads. The material disclosed by the invention is applied to the lithium ion battery, so that the energy density and the cycle performance of the battery can be improved, and the expansion performance of the battery can be reduced.
Description
Technical Field
The invention belongs to the field of preparation of lithium ion battery materials, and particularly relates to a preparation method for preparing an intermediate phase carbon microsphere-silicon carbon composite negative electrode material by an electrochemical deposition method.
Background
The silicon carbon material is a preferred material of a next-generation lithium ion battery cathode material due to high energy density and wide material source, but the silicon carbon material has the defects of large expansion, poor high-temperature storage performance and the like, so that the silicon carbon material is limited to be rapidly popularized in the field of lithium ions. The measures for improving silicon carbon mainly comprise the steps of nanocrystallization of silicon, reduction of expansion due to the structure of a core-shell structure, improvement of silicon expansion in the aspects of silicon, but the measures for improving silicon carbon do not fundamentally reduce the expansion of silicon because a flexible buffer layer is not constructed on the surface of silicon to reduce the expansion of silicon carbon. The mesocarbon microbeads are isotropic spherical structure obtained by polymerizing, extracting and carbonizing asphalt, and have the advantages of stable structure, good cycle performance, low expansion and the like. If the silicon-based precursor is doped between the mesocarbon microbeads to construct a silicon-carbon structure, the expansion in the charge-discharge process is restrained, the expansion of silicon can be reduced, and the cycle performance can be improved. For example, patent application No. 201910270930.1 discloses a preparation method and application of a mesocarbon microbead/nano-silicon composite sphere, wherein the preparation process comprises the steps of carrying out surface modification on nano-silicon powder to obtain nano-silicon powder; dispersing the nano silicon powder with the surface connected with fluorine radicals and tetrahydrofuran solution containing mesocarbon microbead precursors into aqueous solution of polyvinylpyrrolidone to obtain mixed solution; and heating the mixed solution, allowing the intermediate phase carbon microsphere precursor to self-assemble layer by layer in water to coat nano-scale silicon powder, and centrifugally drying to obtain the intermediate phase carbon microsphere/nano-scale silicon composite ball, wherein the prepared composite material can improve expansion and improve specific capacity, but the preparation process is complex, the preparation process of a liquid phase method is difficult to accurately control, and the local agglomeration of the nano-silicon in the intermediate phase precursor is easily caused, so that the material consistency and the electrochemical performance of the nano-silicon are influenced. For another example, patent publication No. CN110931747B discloses a core-shell structure silicon/mesophase carbon microsphere composite anode material and a preparation method thereof, wherein the preparation method comprises mechanically blending carbon-coated nano-silicon and mesophase pitch uniformly, sintering, and separating to obtain the core-shell structure silicon/mesophase carbon microsphere composite material. The core-shell structure silicon/mesocarbon microbead composite material has the hollow nanocage encapsulated silicon unit, improves the charge-discharge specific capacity of a negative electrode material, and has good rate capability and cycle stability, but has the defects of poor consistency, uneven coating thickness, long reaction process time, poor binding force and the like due to the fact that a core and a shell are physically adsorbed together by adopting a liquid phase.
Disclosure of Invention
The invention aims to overcome the defects and provide a preparation method of an intermediate phase carbon microsphere-silicon carbon composite negative electrode material which can improve the energy density and the cycle performance of a battery and reduce the expansion performance of the battery.
The invention relates to a preparation method of a mesocarbon microbead-silicon carbon composite negative electrode material, which comprises the following steps:
(1) Placing the medium temperature asphalt in a reaction kettle, heating to 350-450 ℃ at a heating rate of 1-10 ℃/min, preserving heat for 1-6h to obtain polymerized asphalt, settling, and performing centrifugal separation at 500-1000r/min to obtain mesocarbon microbeads; then, modifying the modified mesocarbon microbeads by using a plasma technology by using 100 percent pure oxygen, 10-50 ccm of oxygen flow, 100-800 mtorr of cavity pressure, 100-400W of power and 5-50 min of processing time to obtain modified mesocarbon microbeads; according to the modified mesocarbon microbeads: mixing the binder and the binder in a mass ratio of 100-20, hot-pressing at 100-200 ℃ and 5T for 10-60min, and pressing on a copper rod to obtain an intermediate phase carbon microsphere composite rod;
(2) Adding a silane coupling agent into an organic solvent to prepare a concentration of 1-5wt%, wherein the silane coupling agent: adding organic lithium salt at the mass ratio of 100 to 10-50, and uniformly dispersing to obtain a solvent;
(3) Taking an intermediate phase carbon microsphere composite rod as a working electrode, taking a solvent as reaction liquid, taking a platinum electrode as a counter electrode, adopting a cyclic voltammetry method, scanning for 10-100 weeks at a scanning speed of 0.1-5mV/s, then washing for 10 times by deionized water, drying for 24 hours in vacuum at 80 ℃ and under-0.09 Mpa, stripping from a copper rod to obtain silicon-containing intermediate phase carbon microspheres, and carbonizing for 6 hours at 800 ℃ to obtain the silicon-based intermediate phase carbon microsphere composite material;
(4) Uniformly mixing the silicon-based intermediate phase carbon microsphere composite material with a reducing agent according to the mass ratio of 10: introducing mixed gas of argon and hydrogen into the reactor at a hydrogen volume ratio of 1-5:1, heating to 800-1200 ℃ at a heating rate of 1-10 ℃/min, reducing for 1-6h, and then cooling in an inert atmosphere to obtain the intermediate phase carbon microsphere-silicon carbon composite cathode material.
The preparation method of the mesocarbon microbeads-silicon carbon composite negative electrode material comprises the following steps: the binder in the step (1) is one of low-temperature asphalt, medium-temperature asphalt, high-temperature asphalt, coal asphalt or petroleum asphalt.
The preparation method of the mesocarbon microbeads-silicon carbon composite negative electrode material comprises the following steps: the silane coupling agent in the step (2) is one of 3-chloropropyltriethoxysilane, 3-chloropropyltrimethoxysilane or 3-bromopropyltrimethoxysilane; the organic solvent is one of ethanol, methanol or isopropanol, N, N-dimethylformamide, N, N-dimethylacetamide or tetrahydrofuran, and dimethyl sulfoxide.
The preparation method of the mesocarbon microbeads-silicon carbon composite negative electrode material comprises the following steps: the organic lithium salt in the step (2) is one of lithium difluoroborate, lithium methyl carbonate, lithium ethyl carbonate, lithium ethylene dicarbonate, lithium ethylene dilithium carbonate, lithium propylene dilithium carbonate, lithium methoxide, lithium ethoxide, lithium formate or lithium oxalate.
The preparation method of the mesocarbon microbeads-silicon carbon composite negative electrode material comprises the following steps: the reducing agent in the step (2) is one of magnesium powder, copper powder, nickel powder or aluminum powder, and the particle size of the reducing agent is 100-1000nm.
Compared with the prior art, the invention has obvious beneficial effects, and the technical scheme can show that: according to the invention, silicon-based materials are deposited in the pores of the mesocarbon microbead composite rod precursor material and on the surface of the mesocarbon microbead composite rod precursor material by an electrochemical deposition method, electrochemical lithium supplement is carried out, and reduction is carried out to obtain the silicon carbon-mesocarbon microbead composite material. According to the invention, a silane coupling agent is used as a silicon source, and a silicon-carbon material with chemical bond connection is obtained by easily combining an alkaline group on the surface of the coupling agent with an oxygen-containing group on the surface of a mesocarbon microbead composite rod, so that the silicon-carbon material has the characteristics of stable structure and the like, and an organic lithium salt deposits lithium on the surface of the organic lithium salt, so that the defects are reduced, and the storage performance is improved; simultaneously, the silicon dioxide formed by the reaction is converted into SiO by reducing gas X And (3) a compound to improve the specific capacity of the material. Thereby improving the energy density and the cycle performance of the battery and reducing the expansion performance of the battery.
Drawings
Fig. 1 is an SEM image of a silicon carbon-mesocarbon microbead composite prepared in example 1.
Detailed Description
Example 1:
an electrochemical deposition method for preparing an intermediate phase carbon microsphere-silicon carbon composite negative electrode material comprises the following steps:
(1) Placing medium temperature asphalt (softening point 80 ℃) in a reaction kettle, heating to 400 ℃ at the heating rate of 5 ℃/min, keeping the temperature for 3h for polymerization reaction to obtain polymerized asphalt, settling, and performing centrifugal separation at 800r/min to obtain mesocarbon microbeads; modifying the carbon microsphere by using a plasma technology (the oxygen flow is 30ccm, the cavity pressure is 500mtorr, the processing time is 20min, and the power is 200W) to obtain a modified mesocarbon microsphere; weighing 100g of modified mesocarbon microbeads, mixing with 10g of high-temperature asphalt (softening point 150 ℃), hot-pressing (pressure of 5T) at 150 ℃ for 30min, and pressing on a copper bar to obtain a mesocarbon microbead composite bar;
(2) Adding 100g of 3-chloropropyltriethoxysilane into 3300ml of ethanol organic solvent to prepare a concentration of 3wt%, and then adding 30g of lithium difluoroborate to disperse uniformly to obtain a solvent;
(3) Adopting an electrochemical deposition method, taking an intermediate phase carbon microsphere composite rod as a working electrode, taking a solvent as reaction liquid, taking a platinum electrode as a counter electrode, adopting a cyclic voltammetry method, scanning for 50 weeks at a scanning speed of 1mV/s, then washing with deionized water for 10 times, drying in vacuum (80 ℃,24h and-0.09 Mpa), stripping from a copper rod to obtain silicon-containing intermediate phase carbon microspheres, and carbonizing for 6h at 800 ℃ to obtain the silicon-based intermediate phase carbon microsphere composite material;
(4) Uniformly mixing 100g of the silicon-based-mesocarbon microbead composite material and 10g of a magnesium powder reducing agent, then introducing a mixed gas of argon and hydrogen (volume ratio, argon: hydrogen =3:1, flow rate 100 ml/min), heating to 950 ℃ at a heating rate of 5 ℃/min, reducing for 3h, and then cooling in an argon inert atmosphere to obtain the mesocarbon microbead-silicon-carbon composite negative electrode material.
Example 2:
an electrochemical deposition method for preparing mesocarbon microbeads-silicon carbon composite negative electrode material comprises the following steps:
(1) Placing medium temperature asphalt (softening point 80 ℃) into a reaction kettle, heating to 350 ℃ at the heating rate of 1 ℃/min, keeping the temperature for 6h for polymerization reaction to obtain polymerized asphalt, and then settling and performing centrifugal separation at 500r/min to obtain mesocarbon microbeads; then, modifying the microspheres by using a plasma technology (the oxygen flow is 10ccm, the cavity pressure is 100mtorr, the processing time is 50min, and the power is 100W) to obtain modified mesocarbon microbeads; weighing 100g of modified mesocarbon microbeads, mixing with 5g of coal pitch (softening point of 200 ℃), hot-pressing at 200 ℃ (pressure of 5T) for 10min, and pressing on a copper rod to obtain a mesocarbon microbead composite rod;
(2) Weighing 100g of 3-chloropropyltrimethoxysilane, adding into 10000ml of isopropanol organic solvent to prepare 1wt% of concentration, adding 10g of lithium methyl carbonate, and dispersing uniformly to obtain a solvent;
(3) Adopting an electrochemical deposition method, taking an intermediate phase carbon microsphere composite rod as a working electrode, taking a solvent as reaction liquid, taking a platinum electrode as a counter electrode, adopting a cyclic voltammetry method, scanning for 10 weeks at a scanning speed of 0.1mV/s, then washing for 10 times by deionized water, carrying out vacuum drying (80 ℃,24h and-0.09 Mpa), stripping from a copper rod to obtain silicon-containing intermediate phase carbon microspheres, and carbonizing for 6h at 800 ℃ to obtain the silicon-based intermediate phase carbon microsphere composite material;
(4) Uniformly mixing 100g of the silicon-based-mesocarbon microbead composite material with 10g of aluminum powder reducing agent, introducing argon and hydrogen mixed gas (volume ratio, argon: hydrogen =1:1, flow rate 100 ml/min), heating to 800 ℃ at a heating rate of 1 ℃/min, reducing for 6h, and cooling in an argon inert atmosphere to obtain the mesocarbon microbead-silicon carbon composite negative electrode material.
Example 3:
an electrochemical deposition method for preparing mesocarbon microbeads-silicon carbon composite negative electrode material comprises the following steps:
(1) Placing medium temperature asphalt (softening point 80 ℃) into a reaction kettle, heating to 450 ℃ at a heating rate of 10 ℃/min, keeping the temperature for 1h for polymerization reaction to obtain polymerized asphalt, and then settling and performing centrifugal separation at 1000r/min to obtain mesocarbon microbeads; then, modifying the microspheres by using a plasma technology (the oxygen flow is 50ccm, the cavity pressure is 800mtorr, the processing time is 5min, and the power is 400W.) to obtain modified mesocarbon microspheres; weighing 100g of modified mesocarbon microbeads, mixing the modified mesocarbon microbeads with 20g of petroleum asphalt (softening point of 200 ℃), hot-pressing at 100 ℃ (pressure of 5T) for 10min, and pressing on a copper bar to obtain a mesocarbon microbead composite bar;
(2) Adding 100g of 3-bromopropyltrimethoxysilane into 2000ml of methanol organic solvent to prepare a concentration of 5wt%, and then adding 50g of lithium methoxide to disperse uniformly to obtain a solvent;
(3) Adopting an electrochemical deposition method, taking an intermediate phase carbon microsphere composite rod as a working electrode, taking a solvent as reaction liquid, taking a platinum electrode as a counter electrode, adopting a cyclic voltammetry method, scanning for 100 weeks at a scanning speed of 5mV/s, then washing with deionized water for 10 times, drying in vacuum (80 ℃,24h and-0.09 Mpa), stripping from a copper rod to obtain silicon-containing intermediate phase carbon microspheres, and carbonizing for 6h at 800 ℃ to obtain the silicon-based intermediate phase carbon microsphere composite material;
(4) Uniformly mixing 100g of the silicon-based-mesocarbon microbead composite material and 10g of nickel powder reducing agent, introducing argon and hydrogen mixed gas (volume ratio, argon: hydrogen =5:1, flow rate: 100 ml/min), heating to 1200 ℃ at a heating rate of 10 ℃/min, reducing for 1h, and cooling in an argon inert atmosphere to obtain the mesocarbon microbead-silicon carbon composite negative electrode material.
Comparative example:
a preparation method of a silicon carbon-mesocarbon microbead composite material comprises the following steps:
weighing 100G of mesocarbon microbeads (Shanghai fir Co., ltd., model G10) on the market and 10G of 3-bromopropyltrimethoxysilane, adding into 2000ml of ethanol solution, uniformly dispersing, filtering, vacuum drying filter residues at 80 ℃ for 24h (vacuum degree: -0.09 Mpa), and carbonizing the filter residues at 800 ℃ for 6h to obtain the mesocarbon microbead-silicon dioxide composite material; weighing 100g of mesocarbon microbead-silicon dioxide composite material, uniformly mixing with 5g of magnesium powder, transferring to a tubular furnace, introducing argon and hydrogen mixed gas (argon: hydrogen =3:1, flow rate 100 ml/min), heating to 1200 ℃ at a heating rate of 10 ℃/min, reducing for 1h, and then cooling in an argon inert atmosphere to obtain the silicon carbon-mesocarbon microbead composite material.
Test example:
performance testing
1.1 SEM test
The silicon carbon-mesocarbon microbead composite material prepared in example 1 was subjected to SEM test, and the test results are shown in fig. 1. As can be seen from the figure, the composite material is spherical and has uniform size distribution, and the particle size of the composite material is between (10 and 20) mu m.
1.2 Powder conductivity test
The silicon carbon-mesocarbon microbeads composite materials of examples 1 to 3 and the comparative example were subjected to a powder conductivity test, which was carried out by the following method: pressing the powder into a blocky structure on a powder compaction density instrument under the pressure of 2T, and then testing the powder conductivity by adopting a four-probe tester. The test results are shown in table 1.
1.3 Tap density, specific surface area, particle size test
According to GB/T243333-2019 graphite cathode materials for lithium ion batteries. The test results are shown in table 1.
TABLE 1 physicochemical Properties of graphite materials in examples and comparative examples
As can be seen from Table 1, the silicon carbon-mesocarbon microbead composites prepared in examples 1-3 of the present invention have significantly higher electrical conductivity and tap density than the comparative examples. The reason is that the silicon-based material is deposited on the surface and in the pores of the mesocarbon microbeads by adopting an electrochemical deposition method, and then is carbonized and reduced to obtain the silicon monoxide which has high density and chemical bond connection, so that the tap density of the composite material is improved and the conductivity is improved.
Experimental example 2 button cell test
The silicon carbon-mesocarbon microbeads composites of examples 1-3 and comparative example were assembled into button cells A1, A2, A3, B1, respectively. The assembling method comprises the following steps: and adding a binder, a conductive agent and a solvent into the negative electrode material, stirring and pulping, coating the mixture on copper foil, and drying and rolling to obtain the negative electrode plate. The binder used was LA132 binder, the conductive agent was SP, the negative electrode material was the silicon carbon-mesocarbon microbead composite material in examples 1-3 and comparative example, respectively, and the solvent was redistilled water. The proportion of each component is: and (3) anode material: SP: LA132: double distilled water =95g:1g:4g:220mL; the electrolyte is LiPF 6 /EC+DEC（LiPF 6 The concentration of the lithium ion battery is 1.2mol/L, the volume ratio of EC to DEC is 1:1), the metal lithium sheet is used as a counter electrode, and the diaphragm is made of a Polyethylene (PE), polypropylene (PP) or polyethylene propylene (PEP) composite film. The button cell is assembled in a glove box filled with argon, electrochemical performance test is carried out on a Wuhan blue electricity CT2001A type battery tester, the charging and discharging voltage range is 0.005V-2.0V, and the charging and discharging multiplying power is 0.1C. The test results are shown in table 2.
Table 2 comparison of electrical properties of examples and comparative examples
As can be seen from table 2, the first discharge capacity and the first charge-discharge efficiency of the lithium ion battery using the silicon carbon-mesocarbon microbead composite material obtained in examples 1 to 3 are significantly higher than those of the comparative example, because the example uses electrochemical deposition to make the binding force between the materials stronger, improve the gram capacity performance of the materials, and simultaneously uses an electrochemical deposition method to supplement lithium with organic lithium to improve the first efficiency of the materials.
Experimental example 3 pouch cell test
The silicon carbon-mesocarbon microbeads composite materials in examples 1 to 3 and comparative example were used as negative electrode materials to prepare negative electrode sheets. A ternary material (LiNi 1/3Co1/3Mn1/3O 2) is used as a positive electrode, a LiPF6 solution (a solvent is EC + DEC, the volume ratio is 1, the concentration of LiPF6 is 1.3 mol/L) is used as an electrolyte, and celegard2400 is used as a diaphragm, so that the 5Ah soft package batteries A1, A2 and A3, B1, B2, B3, B4, B5 and B6 are prepared. And then testing the cycle performance and the rate performance of the soft package battery.
Cycle performance test conditions: the charging and discharging current is 1C/1C, the voltage range is 2.8-4.2V, and the cycle times are 500 times.
Multiplying power performance test conditions: charging rate: 1C/3C/5C/8C, discharge multiplying power of 1C; voltage range: 2.8-4.2V.
The test results are shown in tables 3 and 4.
TABLE 3 comparison of the cycle performance of the examples and comparative examples
As can be seen from table 3, the cycle performance of the pouch battery prepared from the silicon carbon-mesocarbon microbead composite material of the present invention is superior to that of the comparative example, because the electrochemical deposition method has the advantages of uniform and compact deposition and low impedance in the aspect of 1C/1C rate cycle performance, the cycle is improved, and the internal resistance is reduced, i.e., the silicon carbon-mesocarbon microbead composite material prepared in the example has better cycle and lower DCR.
Table 4 multiplying power charging performance comparison table
As can be seen from table 4, the soft-package batteries prepared from the silicon carbon-mesocarbon microbead composite materials of examples 1 to 3 of the present invention have a better constant current ratio, because the materials of the examples deposit silicon compounds on the surfaces of the modified mesocarbon microbeads thereof by an electrochemical deposition method, and the surface active groups of the modified mesocarbon microbeads and the groups of the silane coupling agent are connected by chemical bonds to form new groups, so that the new groups have a lower internal resistance and the rate capability, i.e., a higher constant current ratio, is improved.
The present invention is not limited to the above preferred embodiments, and any modifications, equivalent substitutions, improvements, etc. within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (5)
1. A preparation method of a mesocarbon microbead-silicon carbon composite negative electrode material comprises the following steps:
(1) Placing the medium-temperature asphalt in a reaction kettle, heating to 350-450 ℃ at a heating rate of 1-10 ℃/min, preserving heat for 1-6h to obtain polymerized asphalt, settling, and performing centrifugal separation at 500-1000r/min to obtain mesocarbon microbeads; modifying 100 percent pure oxygen with the oxygen flow of 10-50 ccm, the cavity pressure of 100-800 mtorr, the power of 100-400W and the processing time of 5-50 min to obtain modified mesocarbon microbeads; according to the modified mesocarbon microbeads: mixing the binder and the binder in a mass ratio of 100-20, hot-pressing at 100-200 ℃ and 5T for 10-60min, and pressing on a copper rod to obtain an intermediate phase carbon microsphere composite rod;
(2) Adding a silane coupling agent into an organic solvent to prepare a concentration of 1-5wt%, wherein the silane coupling agent: adding organic lithium salt in a mass ratio of 100; wherein the silane coupling agent is one of 3-chloropropyltriethoxysilane, 3-chloropropyltrimethoxysilane or 3-bromopropyltrimethoxysilane;
(3) Taking an intermediate phase carbon microsphere composite rod as a working electrode, taking a solvent as reaction liquid, taking a platinum electrode as a counter electrode, adopting a cyclic voltammetry method, scanning for 10-100 weeks at a scanning speed of 0.1-5mV/s, then washing for 10 times by deionized water, drying for 24 hours in vacuum at 80 ℃ and under-0.09 Mpa, stripping from a copper rod to obtain silicon-containing intermediate phase carbon microspheres, and carbonizing for 6 hours at 800 ℃ to obtain the silicon-based intermediate phase carbon microsphere composite material;
(4) Uniformly mixing the silicon-based intermediate phase carbon microsphere composite material with a reducing agent according to the mass ratio of 10: introducing mixed gas of argon and hydrogen into the reactor at a hydrogen volume ratio of 1-5:1, heating to 800-1200 ℃ at a heating rate of 1-10 ℃/min, reducing for 1-6h, and then cooling in an inert atmosphere to obtain the mesocarbon microbead-silicon carbon composite anode material.
2. The method for preparing the mesocarbon microbeads-silicon carbon composite negative electrode material of claim 1, wherein: the binder in the step (1) is one of low-temperature asphalt, medium-temperature asphalt, high-temperature asphalt, coal asphalt or petroleum asphalt.
3. The method for preparing the mesocarbon microbead-silicon carbon composite anode material as claimed in claim 1, wherein: the organic solvent in the step (2) is one of ethanol, methanol or isopropanol, N, N-dimethylformamide, N, N-dimethylacetamide or tetrahydrofuran and dimethyl sulfoxide.
4. The method for preparing the mesocarbon microbead-silicon carbon composite anode material as claimed in claim 1, wherein: the organic lithium salt in the step (2) is one of lithium difluoroborate, lithium methyl carbonate, lithium ethyl carbonate, lithium ethylene dicarbonate, lithium ethylene dilithium carbonate, lithium propylene dilithium carbonate, lithium methoxide, lithium ethoxide, lithium formate or lithium oxalate.
5. The method for preparing the mesocarbon microbead-silicon carbon composite anode material as claimed in claim 1, wherein: the reducing agent in the step (2) is one of magnesium powder, copper powder, nickel powder or aluminum powder, and the particle size of the reducing agent is 100-1000nm.
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| Jialing Zou.Electroless copper plating mechanism of mesophase pitch-based carbon fibers by the grafting modification of silane couple agent.2022,全文. * |
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