锂铁磷酸盐LiFePO_4的制备及高压原位研究
摘要
本文首先研究了锂铁磷酸盐LiFePO_4的制备情况,通过在氮气保护气氛下,以Li_2CO_3、NH4H2PO_4、Fe_2O_3和葡萄糖为原料,利用碳热还原法合成了碳包覆的LiFePO_4材料。对LiFePO_4常压下的结构进行了研究,并给出了LiFePO_4常压下的拉曼活性振动模式。随后利用拉曼光谱和同步辐射X射线衍射技术对LiFePO_4进行了高压原位研究,给出了LiFePO_4随压力变化的拉曼光谱和晶格常数。本文还在LiFePO_4碳包覆的基础上进行了金属离子掺杂研究,本文分别掺杂了Zn~(2+)、Cu~(2+)、Ni~(2+)、Co~(2+)、Co~(3+)、Mn~(4+)金属离子,并对掺杂样品进行了表征,且讨论了掺杂结果。
As a new replaceable energy material, lithium ion batteries have attracted a lot of research interests. Lithium ion battery has high capacity, and is environmentally recycled. Now, the studies of lithium ion batteries are mainly concentrated in battery capacity and enhanced electrochemical performance. By improving the anode materials of lithium ion batteries to higher battery capacity, it has become the current research direction. Among these anode materials, lithium iron phosphate LiFePO_4 has been investigated quite thoroughly. LiFePO_4 has low toxicity and good reversibility, and the big anions in crystal structure can stable the whole structure. By carbon-encapsulating or metal ions doping, it can improve the capacity of LiFePO_4.
In this thesis, at the protective atmosphere with nitrogen,Li_2CO_3, Fe_2O_3 and glucose NH4H2PO_4 used as raw materials, carbon-encapsulated LiFePO_4 materials have been synthesized by carbonthermal reduction method. The XRD analysis shows the agreements with the standard PDF card. Meanwhile, the crystal structure of LiFePO_4 was studied, and besides its Raman active vibration modes at ambient pressure.
Raman spectroscopy and synchrotron radiation X-ray diffraction technique are used for in-situ studies of LiFePO_4 under high pressure. The Raman spectra and the changes of lattice constants at high pressure have been presented. High-pressure Raman spectra show that all Raman modes are shifted to higher wave numbers with the increase of the pressure. Some Raman modes related with the vibrations of PO_4 cluster are obviously enhanced at high pressure. While releasing the pressures, no internal stress is found. The lattice constants and the unit cell volume become smaller continuously with the pressure increasing pressure.
The doping effects of different kinds of metal ions have been studied on the base of carbon-encapsulated LiFePO_4. In this thesis, doping of Zn~(2+), Cu~(2+), Ni~(2+), Co~(2+), Co~(3+), and Mn~(4+) metal ions have been investigated, and the samples are characterized by XRD and Raman spectroscopy. The results show that the metal ions can be easily doped into LiFePO_4, without any new structure change. Namely, they can from solid solution with LiFePO_4 as LiFe_(1-x)M_xPO_4 (M = Zn~(2+) Cu~(2+), Ni~(2+), Co~(2+), Co~(3+), Mn~(4+)).
As a new replaceable energy material, lithium ion batteries have attracted a lot of research interests. Lithium ion battery has high capacity, and is environmentally recycled. Now, the studies of lithium ion batteries are mainly concentrated in battery capacity and enhanced electrochemical performance. By improving the anode materials of lithium ion batteries to higher battery capacity, it has become the current research direction. Among these anode materials, lithium iron phosphate LiFePO_4 has been investigated quite thoroughly. LiFePO_4 has low toxicity and good reversibility, and the big anions in crystal structure can stable the whole structure. By carbon-encapsulating or metal ions doping, it can improve the capacity of LiFePO_4.
In this thesis, at the protective atmosphere with nitrogen,Li_2CO_3, Fe_2O_3 and glucose NH4H2PO_4 used as raw materials, carbon-encapsulated LiFePO_4 materials have been synthesized by carbonthermal reduction method. The XRD analysis shows the agreements with the standard PDF card. Meanwhile, the crystal structure of LiFePO_4 was studied, and besides its Raman active vibration modes at ambient pressure.
Raman spectroscopy and synchrotron radiation X-ray diffraction technique are used for in-situ studies of LiFePO_4 under high pressure. The Raman spectra and the changes of lattice constants at high pressure have been presented. High-pressure Raman spectra show that all Raman modes are shifted to higher wave numbers with the increase of the pressure. Some Raman modes related with the vibrations of PO_4 cluster are obviously enhanced at high pressure. While releasing the pressures, no internal stress is found. The lattice constants and the unit cell volume become smaller continuously with the pressure increasing pressure.
The doping effects of different kinds of metal ions have been studied on the base of carbon-encapsulated LiFePO_4. In this thesis, doping of Zn~(2+), Cu~(2+), Ni~(2+), Co~(2+), Co~(3+), and Mn~(4+) metal ions have been investigated, and the samples are characterized by XRD and Raman spectroscopy. The results show that the metal ions can be easily doped into LiFePO_4, without any new structure change. Namely, they can from solid solution with LiFePO_4 as LiFe_(1-x)M_xPO_4 (M = Zn~(2+) Cu~(2+), Ni~(2+), Co~(2+), Co~(3+), Mn~(4+)).
引文
[1]吴宇平,戴晓兵,等.锂离子电池-应用与实践[M].北京:化学工业出版社, 2004.
[2]吴宇平,张汉平,等.聚合物锂离子电池[M].北京:化学工业出版社,2007.
[3]艾德生,高喆.新能源材料-基础与应用[M].北京:化学工业出版社,2010.
[4]吴宇平,张汉平,吴锋.绿色电源材料[M].北京:化学工业出版社,2008.
[5]黄可龙,王兆翔,刘素琴.锂离子电池原理与关键技术[M].北京:化学工业出版社,2008.
[6]晋勇,孙小松,薛屺.X射线衍射分析技术[M].北京:国防工业出版社,2008.
[7][苏]齐克利斯著.王殿儒,罗明晖译.高压和超高压物理-化学研究技术[M].北京:科学出版社,1983.
[8]徐彭寿,潘国强.同步辐射应用基础[M].安徽:中国科技大学出版社,2009.
[9]渡边诚,佐藤繁.同步辐射科学基础[M].上海:上海交通大学出版社,2010.
[10]刘丹.A2O3(C-RES)和BO3型金属氧化物的高压结构相变研究[D].长春:吉林大学超硬材料国家重点实验室,2009.
[11]PAULSEN J M, MUELLER-NEUHAUS J R,DAHN J R.Layered LiCoO2 with a different oxygen stacking(O2 structure)as a cathode material for rechargeable lithium batteries[J]. J Electrochemical Soc, 2000, 147(2): 508-516.
[12]ROUGIER A, GRAVEREAU P, DELMAS C.Optimization of the Composition of the Lil-ZNil+ZO2 Electrocde Materials:Structural,Magnetic,and Electochimica Studies [J]. J Electrochemical Soc, 1996, 143: 1168-1175.
[13]WANG Z X, WU C, LIU L J, et al.Electrochemical Evaluation and Structural Characterization of Commercial LiCoO2 Surfaces Modified with MgO for Lithium-Ion Batteries[J]. J Electrochemical Soc, 2002, 149(4): A466-A471.
[14]LIU L J, WANG ZX, Li H, et al. Al2O3-coated LiCoO2 as cathode material for lithium ion batteries[J]. Solid State Ionic, 2002, 152– 153: 341– 346.
[15]WANG Z X, LIU L J, CHEN L Q, et al. Structural and electrochemical characterizations of surface-modified LiCoO2 cathode materials for Li-ion batteries[J].Solid State Ionic, 2002, 148: 335– 342.
[16]KANNAN A M, RABENBERG L, MANTHIRAM A. High Capacity Surface-Modified LiCoO2 Cathodes for Lithium-Ion Batteries[J]. Electrochemical andSolid-State Letters, 2003, 6(1): A16-A18.
[17]HIRANO A, KANIE K, et al.Neutron diffraction study on layered rocksalt Li1_xNi1+xO2 at high temperature[J]. Solid State Ionic, 2002, 152– 153: 207– 216.
[18]ARAI H, TSUDA M, SAITO K, et al. Thermal Reactions Between Delithiated Lithium Nickelate and Electrolyte Solutions[J]. J Electrochemical Soc, 2002, 149 (4): A401-A406.
[19]YAMADA A, KUDO Y.Phase Diagram of Lix(MnyFel1-y)PO4(0≤x,y≤1) [J].J Electrochem Soc, 2001, 148(10): Al 153-Al 158.
[20]HWANG B J,SANTHANAM R,LIU D G.Effect of Various Synthetic Parameters on Purity of LiMn2O4 Spinel Synthesized by a Sol-gel Method at Low Temperature[J].J.Power Sources, 2001, 101: 86-89.
[21]HON Y M,LIN S P,FUNG K Z,HON M H.Synthesis and Characterization of Nano-LiMn2O4 Powder by Tartaric Acid Gel Process[J].J European Ceramic Society,2002,(22): 653-660.
[22]DEB A, BERGMANN U, GAIRNS E J et al. X-ray absorption spectroscopy study of the LixFePO4 cathode during cycling using a novel electrochemical in situ reaction cell[J]. Synchrotron Rad, 2004, 11: 497-504.
[23]YAMADA A, CHUNG S. Crystal Chemistry of the Olivine-Type Li(MnyFe1-y)PO4 and (MnyFe1-y)PO4 as Possible 4 V Cathode Materials forLithium Batteries[J]. J. Electrochem. Soc., 2001, 148(8): A960-A967.
[24]DELACOURT C, RODRIGUEZ-CARVAJAL J, SCHMITT B, et al. Crystal chemistry of the olivine-type LixFePO4 system (0≤x≤1) between 25 and 370℃[J]. Solid State sciences, 2005, 7: 1506-1516.
[25]PADHI A K, NANJUNDASWAMY K S, GOODENOUGH J B. Phospho -olivines as Positive-Electrode Materials forRechargeable Lithium Batteries[J]. J Electrochem Soc, 1997, 144(4): 1188-1193.
[26]ANDERSSON A S, THOMAS J O. The source of first-cycle capacity loss in LiFePO4[J]. J. Power Source, 2001, 97-98: 498-502.
[27]RAVET N, CHOUINARD Y, MAGNAN J F, et al.Electroactivity of natural and synthetic triphylite[J].J. Power Sources, 2001, 97-98: 503-507.
[28]YAMADA A, CHUNG S C, HINOKUMA K. Optimized LiFePO4 for Lithium Battery Cathodes [J]. J. Electrochem. Soc., 2001, 148(3): A224-A229.
[29]BARKER J, SAIDI M Y, SWOYER J L. Lithium Iron(II)Phospho-olivinesPrepared by a Novel Carbothermal Reduction Method [J].Electrochemical and Solid-State Letters, 2003, 6 (3) : A53-A55.
[30]HIGUCHI M, KATAYAMA K, AZUMA Y, et al. Synthesis of LiFePO4 cathode material by microwave processing[J]. Journal of Power Sources, 2003, 119–121: 258–261.
[31]TUCKER M C, DOEFF M M, RICHARDSON T J, et al. 7Li and 31P magic angle spinning nuclear magnetic resonance of LiFePO4 type materials[J]. Electrochem.Solid State Lett., 2002, 5(5): A95-98.
[32]Shoufeng Y,PETER Y Z.WHTTINGGHAM M S.Hydrothermal synthesis of lithium iron phosphate cathodes[J].Electrochemistry Communications, 2001, 3(9): 505-508.
[33]ARNOLD G, GARCHE J, HEMMER R, et al. Fine-particle lithium iron phosphate LiFePO4 synthesized by a new low-cost aqueous precipitation technique[J]. J.Power Sources, 2003, 119-121: 247-251.
[34]CROCE F, EPIFANIO A D, HASSOUN J, et al. A novel concept for the synthesis of an improved LiFePO4 liuthium battery cathode[J].Electrochem.Solid State Lett.,2002 ,5(3): A47-A50
[35]FRANGER S,LE CRAS F,BOURBON B,et al.LiFePO4 synthesis routes for enhanced electrochemical performance[J]. J.Electrochem.Soc., 2002, 5(10): A231- A233.
[36]Myung S T,Komaba S, Hirosald N, et al. Emulsion drying synthesis of olivine LiFePO4/C composite and its electrochemical properties as lithium intercalation material[J].Electrochimica Acta, 2004, 49: 4213–4222.
[37]GAO F, TANG Z Y, XUE H J. Preparation and characterization of nano-particle LiFePO4 and LiFePO4/C by spray-drying and post-annealing method [J]. Electraochem Acta, 2007, 53(4): 1939-1944.
[38]KONAROVA M, TANIGUCHI I. Preparation of carbon coated LiFePO4 by a combination of spray pyrolysis with planetary ball-milling followed by heat treatment and their electrochemical properties[J]. Powder Technology, 2009, 191: 111–116.
[39]KUZUBA T, SATO Y, YAMAOKA S, ERA K.Raman-scattering study of high-pressure effects on the anisotropy of force constants of hexagonal boron nitride[J]. Phys. Rev. B, 1978, 18: 4440–4443.
[40]WU X L, JIANG L Y, CAO F F,et al. LiFePO4 Nanoparticles Embedded in a Nanoporous Carbon Matrix: Superior Cathode Material for ElectrochemicalEnergy-Storage Devices[J]. Adv. Mater., 2009, 21: 2710–2714.
[41]KIM J K, CHOI J W, CHAUHAN G S, et al. Enhancement of electrochemical performance of lithium iron phosphate by controlled sol-gel synthesis [J]. Elegtrochimica Acta, 2008, 53(28): 8258-8264.
[42]BURBA C M, FRECH R. Raman and FTIR Spectroscopic Study of LixFePO4 ( 0≤x≤1) [J]. J. Electrochem. Soc., 2004, 151(7): A1032-A1038.
[43]BURBA C M, PALMER J M, HOLINSWORTH B S. Laser-induced phase changes in olivine FePO4: a warning on characterizing LiFePO4-based cathodes with Raman spectroscopy[J]. J. Raman Spectrosc, 2009, 40:225–228.
[44]倪江锋,周恒辉,等.铬离子掺杂对LiFePO4电化学性能的影响[J].物理化学学报,2004,20(6):582-586.
[45]CHUNG S Y, BLOKING J T,CHIANG Y M. Electronically conductive phospho-olivines as lithium storage electrodes[J]. Nature Materials, 2002, 1:123-128.
[46]HUA N, WANG C Y, KANG X Y, et al. Synthesis and Electrochemical Characterizations of Zinc-doped LiFePO4/C by Carbothermal Reduction[J]. Journal of Inorganic Materials, 2010, 25(8): 887-892.
[2]吴宇平,张汉平,等.聚合物锂离子电池[M].北京:化学工业出版社,2007.
[3]艾德生,高喆.新能源材料-基础与应用[M].北京:化学工业出版社,2010.
[4]吴宇平,张汉平,吴锋.绿色电源材料[M].北京:化学工业出版社,2008.
[5]黄可龙,王兆翔,刘素琴.锂离子电池原理与关键技术[M].北京:化学工业出版社,2008.
[6]晋勇,孙小松,薛屺.X射线衍射分析技术[M].北京:国防工业出版社,2008.
[7][苏]齐克利斯著.王殿儒,罗明晖译.高压和超高压物理-化学研究技术[M].北京:科学出版社,1983.
[8]徐彭寿,潘国强.同步辐射应用基础[M].安徽:中国科技大学出版社,2009.
[9]渡边诚,佐藤繁.同步辐射科学基础[M].上海:上海交通大学出版社,2010.
[10]刘丹.A2O3(C-RES)和BO3型金属氧化物的高压结构相变研究[D].长春:吉林大学超硬材料国家重点实验室,2009.
[11]PAULSEN J M, MUELLER-NEUHAUS J R,DAHN J R.Layered LiCoO2 with a different oxygen stacking(O2 structure)as a cathode material for rechargeable lithium batteries[J]. J Electrochemical Soc, 2000, 147(2): 508-516.
[12]ROUGIER A, GRAVEREAU P, DELMAS C.Optimization of the Composition of the Lil-ZNil+ZO2 Electrocde Materials:Structural,Magnetic,and Electochimica Studies [J]. J Electrochemical Soc, 1996, 143: 1168-1175.
[13]WANG Z X, WU C, LIU L J, et al.Electrochemical Evaluation and Structural Characterization of Commercial LiCoO2 Surfaces Modified with MgO for Lithium-Ion Batteries[J]. J Electrochemical Soc, 2002, 149(4): A466-A471.
[14]LIU L J, WANG ZX, Li H, et al. Al2O3-coated LiCoO2 as cathode material for lithium ion batteries[J]. Solid State Ionic, 2002, 152– 153: 341– 346.
[15]WANG Z X, LIU L J, CHEN L Q, et al. Structural and electrochemical characterizations of surface-modified LiCoO2 cathode materials for Li-ion batteries[J].Solid State Ionic, 2002, 148: 335– 342.
[16]KANNAN A M, RABENBERG L, MANTHIRAM A. High Capacity Surface-Modified LiCoO2 Cathodes for Lithium-Ion Batteries[J]. Electrochemical andSolid-State Letters, 2003, 6(1): A16-A18.
[17]HIRANO A, KANIE K, et al.Neutron diffraction study on layered rocksalt Li1_xNi1+xO2 at high temperature[J]. Solid State Ionic, 2002, 152– 153: 207– 216.
[18]ARAI H, TSUDA M, SAITO K, et al. Thermal Reactions Between Delithiated Lithium Nickelate and Electrolyte Solutions[J]. J Electrochemical Soc, 2002, 149 (4): A401-A406.
[19]YAMADA A, KUDO Y.Phase Diagram of Lix(MnyFel1-y)PO4(0≤x,y≤1) [J].J Electrochem Soc, 2001, 148(10): Al 153-Al 158.
[20]HWANG B J,SANTHANAM R,LIU D G.Effect of Various Synthetic Parameters on Purity of LiMn2O4 Spinel Synthesized by a Sol-gel Method at Low Temperature[J].J.Power Sources, 2001, 101: 86-89.
[21]HON Y M,LIN S P,FUNG K Z,HON M H.Synthesis and Characterization of Nano-LiMn2O4 Powder by Tartaric Acid Gel Process[J].J European Ceramic Society,2002,(22): 653-660.
[22]DEB A, BERGMANN U, GAIRNS E J et al. X-ray absorption spectroscopy study of the LixFePO4 cathode during cycling using a novel electrochemical in situ reaction cell[J]. Synchrotron Rad, 2004, 11: 497-504.
[23]YAMADA A, CHUNG S. Crystal Chemistry of the Olivine-Type Li(MnyFe1-y)PO4 and (MnyFe1-y)PO4 as Possible 4 V Cathode Materials forLithium Batteries[J]. J. Electrochem. Soc., 2001, 148(8): A960-A967.
[24]DELACOURT C, RODRIGUEZ-CARVAJAL J, SCHMITT B, et al. Crystal chemistry of the olivine-type LixFePO4 system (0≤x≤1) between 25 and 370℃[J]. Solid State sciences, 2005, 7: 1506-1516.
[25]PADHI A K, NANJUNDASWAMY K S, GOODENOUGH J B. Phospho -olivines as Positive-Electrode Materials forRechargeable Lithium Batteries[J]. J Electrochem Soc, 1997, 144(4): 1188-1193.
[26]ANDERSSON A S, THOMAS J O. The source of first-cycle capacity loss in LiFePO4[J]. J. Power Source, 2001, 97-98: 498-502.
[27]RAVET N, CHOUINARD Y, MAGNAN J F, et al.Electroactivity of natural and synthetic triphylite[J].J. Power Sources, 2001, 97-98: 503-507.
[28]YAMADA A, CHUNG S C, HINOKUMA K. Optimized LiFePO4 for Lithium Battery Cathodes [J]. J. Electrochem. Soc., 2001, 148(3): A224-A229.
[29]BARKER J, SAIDI M Y, SWOYER J L. Lithium Iron(II)Phospho-olivinesPrepared by a Novel Carbothermal Reduction Method [J].Electrochemical and Solid-State Letters, 2003, 6 (3) : A53-A55.
[30]HIGUCHI M, KATAYAMA K, AZUMA Y, et al. Synthesis of LiFePO4 cathode material by microwave processing[J]. Journal of Power Sources, 2003, 119–121: 258–261.
[31]TUCKER M C, DOEFF M M, RICHARDSON T J, et al. 7Li and 31P magic angle spinning nuclear magnetic resonance of LiFePO4 type materials[J]. Electrochem.Solid State Lett., 2002, 5(5): A95-98.
[32]Shoufeng Y,PETER Y Z.WHTTINGGHAM M S.Hydrothermal synthesis of lithium iron phosphate cathodes[J].Electrochemistry Communications, 2001, 3(9): 505-508.
[33]ARNOLD G, GARCHE J, HEMMER R, et al. Fine-particle lithium iron phosphate LiFePO4 synthesized by a new low-cost aqueous precipitation technique[J]. J.Power Sources, 2003, 119-121: 247-251.
[34]CROCE F, EPIFANIO A D, HASSOUN J, et al. A novel concept for the synthesis of an improved LiFePO4 liuthium battery cathode[J].Electrochem.Solid State Lett.,2002 ,5(3): A47-A50
[35]FRANGER S,LE CRAS F,BOURBON B,et al.LiFePO4 synthesis routes for enhanced electrochemical performance[J]. J.Electrochem.Soc., 2002, 5(10): A231- A233.
[36]Myung S T,Komaba S, Hirosald N, et al. Emulsion drying synthesis of olivine LiFePO4/C composite and its electrochemical properties as lithium intercalation material[J].Electrochimica Acta, 2004, 49: 4213–4222.
[37]GAO F, TANG Z Y, XUE H J. Preparation and characterization of nano-particle LiFePO4 and LiFePO4/C by spray-drying and post-annealing method [J]. Electraochem Acta, 2007, 53(4): 1939-1944.
[38]KONAROVA M, TANIGUCHI I. Preparation of carbon coated LiFePO4 by a combination of spray pyrolysis with planetary ball-milling followed by heat treatment and their electrochemical properties[J]. Powder Technology, 2009, 191: 111–116.
[39]KUZUBA T, SATO Y, YAMAOKA S, ERA K.Raman-scattering study of high-pressure effects on the anisotropy of force constants of hexagonal boron nitride[J]. Phys. Rev. B, 1978, 18: 4440–4443.
[40]WU X L, JIANG L Y, CAO F F,et al. LiFePO4 Nanoparticles Embedded in a Nanoporous Carbon Matrix: Superior Cathode Material for ElectrochemicalEnergy-Storage Devices[J]. Adv. Mater., 2009, 21: 2710–2714.
[41]KIM J K, CHOI J W, CHAUHAN G S, et al. Enhancement of electrochemical performance of lithium iron phosphate by controlled sol-gel synthesis [J]. Elegtrochimica Acta, 2008, 53(28): 8258-8264.
[42]BURBA C M, FRECH R. Raman and FTIR Spectroscopic Study of LixFePO4 ( 0≤x≤1) [J]. J. Electrochem. Soc., 2004, 151(7): A1032-A1038.
[43]BURBA C M, PALMER J M, HOLINSWORTH B S. Laser-induced phase changes in olivine FePO4: a warning on characterizing LiFePO4-based cathodes with Raman spectroscopy[J]. J. Raman Spectrosc, 2009, 40:225–228.
[44]倪江锋,周恒辉,等.铬离子掺杂对LiFePO4电化学性能的影响[J].物理化学学报,2004,20(6):582-586.
[45]CHUNG S Y, BLOKING J T,CHIANG Y M. Electronically conductive phospho-olivines as lithium storage electrodes[J]. Nature Materials, 2002, 1:123-128.
[46]HUA N, WANG C Y, KANG X Y, et al. Synthesis and Electrochemical Characterizations of Zinc-doped LiFePO4/C by Carbothermal Reduction[J]. Journal of Inorganic Materials, 2010, 25(8): 887-892.