采用放电等离子烧结(spark plasma sintering, SPS)工艺制备碳纤维增强碳化硼(Cf/B4C)复合材料,通过X射线衍射和激光拉曼光谱对聚丙烯腈(polyacrylonitrile, PAN)基碳纤维石墨化度进行表征,重点研究烧结温度、烧结压力和保温时间对碳纤维石墨化的影响。结果表明,温度、压力和保温时间均对碳纤维石墨化有影响,其中烧结温度的影响最明显。烧结温度为2 000 ℃时,碳纤维的(002)晶面间距d(002)和拉曼光谱中D峰强度ID与G峰强度IG的比值分别为0.336 nm和0.377,石墨化度达到92.21%。根据XRD所测的石墨化度和拉曼光谱中R-1的对应关系,拟合得到拉曼光谱表征碳纤维石墨化度的公式。SPS下PAN基碳纤维的低温石墨化是由于SPS综合了温度、压力和电流的影响,以溶解-再析出为主要催化机理,其中界面活化程度或许是产生碳纤维石墨化度差异的根本原因。
In this paper, the Cf/B4C composites were fabricated by spark plasma sintering (SPS). The graphitization degree of polyacrylonitrile (PAN) carbon fibers was characterized by X-ray diffraction and Laser Raman spectroscopy. The effects of sintering temperature, sintering pressure and holding time on the graphitization of carbon fibers were focused on. The results show that temperature, pressure and holding time have certain effects on the graphitization of carbon fibers, and the effect of temperature is the most obvious. When the sintering temperature reaches 2 000 ℃, the crystal plane spacing d(002) of carbon fiber by XRD and Raman peak intensity ratio (ID/IG) is 0.336 nm and 0.377 respectively, and the graphitization degree of carbon fibers reaches 92.21%. According to the corresponding relationship between the graphitization degree measured by XRD and Raman spectrum, the graphitization degree formula of carbon fibers characterized by Raman spectrum is fitted. The low-temperature graphitization of PAN carbon fibers under SPS is due to the fact that SPS combines the influences of temperature, pressure and current. In addition, the main catalytic mechanism is dissolution and reprecipitation. The difference of interfacial activation may be the fundamental reason for the different graphitization degree of carbon fibers.
[1] ZHAIY P, QIAN Y. ZHAO D Y, et al.Carbon materials for chemical capacitive energy storage[J]. Advanced Materials, 2011, 23(42): 4028-4050.
[2] JAYASRI D, NARAYANAN S S.Electrocatalytic oxidation and amperometric determination of BHA at graphite-wax composite electrode with silver hexacyanoferrate as electrocatalyst[J]. Sensors & Actuators B Chemical, 2006, 119(1): 135-42.
[3] MILLER J R, SIMON P.Electrochemical capacitors for energy management[J]. Science, 2008, 321(5889): 651-652.
[4] BROUSSE T, BéLANGER D, CHIBA K, et al. Materials for Electrochemical Capacitors[M]. Berlin: Springer-Verlag Berlin Heidelberg, Springer Handbook of Electrochemical Energy, 2017.
[5] LI M F, LIU Y G, ZENG G M, et al.Graphene and graphene-based nanocomposites used for antibiotics removal in water treatment: A review[J]. Chemosphere, 2019, 226: 360-380.
[6] SUN L H, LI M, SHANG L, et al.The influence of oxygen on skin-core structure of polyacrylonitrile-based precursor fibers[J]. Polymer, 2020, 197(8): 122516.
[7] LIN Q Y, FENG Z H, LIU Z J, et al.Atomic scale investigations of catalyst and catalytic graphitization in a silicon and titanium doped graphite[J]. Carbon, 2015, 88: 252-261.
[8] HUANG Z H, ZHU H H, PENG Q L, et al.Catalytic graphitization of polyacrylonitrile (PAN)-based carbon fibers with Fe-Cr2O3 composite coating[J]. Transactions of Nonferrous Metals Society of China, 2010, 20(8): 1418-1423.
[9] DESTYORINI F, YUDIANTI R, IRMAWATI Y, et al.Temperature driven structural transition in the nickel-based catalytic graphitization of coconut coir[J]. Diamond and Related Materials, 2021, 117: 108443.
[10] LI H T, ZHANG H, LI K J, et al.Catalytic graphitization of coke carbon by iron: Understanding the evolution of carbon Structure, morphology and lattice fringes[J]. Fuel, 2020, 279: 118531.
[11] SONI R U, EDLABADKAR V A, REWATKAR P M, et al.Low-temperature catalytic synthesis of graphite aerogels from polyacrylonitrile-crosslinked iron oxide and cobalt oxide xerogel powders[J]. Carbon, 2022, 193(30): 107-127.
[12] XIA S W, CAI N, LU W, et al.Reaction kinetics, mechanism, and product analysis of the iron catalytic graphitization of cellulose[J]. Journal of Cleaner Production, 2021, 329(20): 129735.
[13] LEE S, CHO S Y, CHUNG Y S, et al.High electrical and thermal conductivities of a PAN-based carbon fiber via boron-assisted catalytic graphitization[J]. Carbon, 2022, 199(31): 70-79.
[14] CHEN H J, YANG J X, SHUAI Q, et al.In-situ doping B4C nanoparticles in PAN precursors for preparing high modulus PAN-based carbon fibers with boron catalytic graphitization[J]. Composites Science and Technology, 2020, 200(10): 108455.
[15] ZHOU H H, YU Q, PENG Q L, et al.Catalytic graphitization of carbon fibers with electrodeposited Ni-B alloy coating[J]. Materials Chemistry and Physics, 2008, 110(2/3): 434-439.
[16] 李崇俊, 马伯信, 霍肖旭, 等. 碳化硼对碳/碳复合材料的催化石墨化作用[J]. 宇航材料工艺, 1997, 5: 34-37.
LI Chongjun, MA Boxin, HUO Xiaoxu, et al.Catalytic graphitization of carbon/carbon composites by boron carbide[J]. Aerospace Material Technology, 1997, 05: 34-37.
[17] HISHIYAMA Y, INAGAKI M, KIMURA S, et al.Graphitization of carbon fibre/glassy carbon composites[J]. Carbon, 1974, 12(3): 255-258.
[18] ZHANG F Q, HUANG Q Z, HUANG B Y, et al.Charaterization of graphitization degree of C/C composites by laser raman microspectroscopy[J]. Journal of Inorganic Materials, 2003, 18(2): 361-366.
[19] ZALDIVARR J, RELLICK G S.Some observations on stress graphitization in carbon-carbon composites[J]. Carbon, 1991, 29(8): 1155-1163.
[20] MATSUI K, LANTICSE L J, TANABE Y, et al.Stress graphitization of C/C composite reinforced by carbon nanofiber[J]. Carbon, 2005, 43(7): 1577-1579.
[21] FRANKLIN R E.The structure of graphitic carbons[J]. Acta Crystallographica, 1951, 4(3): 253-261.
[22] 稻垣道夫, 刘洪波. 石墨化度的评价[J]. 炭素技术, 1991, 5(10): 38-43.
DAOHUAN Daofu, LIU Hongbo.Evaluation of the degree of graphitization[J]. Carbon Technology, 1991, 5(10): 38-43.
[23] FITZER E, ROZPLOCH F.Laser Raman spectroscopy for determination of the C-C bonding length in carbon[J]. carbon, 1988, 26(4): 594-595.
[24] JAWHARI T, ROID A, CASADO J.Raman spectroscopic characterization of some commercially available carbon black materials[J]. Carbon, 1995, 33(11): 1561-1565.
[25] KAKIHANA M, OSADA M.Raman spectroscopy as a characterization tool for carbon materials[J]. Elsevier Ltd, 2003, 285-298.
[26] 张福勤. 航空刹车用C/C复合材料石墨化度的研究[D]. 长沙: 中南大学, 2002.
ZHANG Fuqin.Study on graphitization degree of C/C composites for aviation brakes[D]. Changsha: Central South University, 2002.
[27] ZHANG F Q, HUANG Q Z, HUANG B Y, et al.Charaterization of graphitization degree of C/C Composites by laser raman microspectroscopy[J]. Journal of Inorganic Materials, 2003, 18(2): 361-366.