Preparation of Spherical FePO₄ by Chemical Co-precipitation Combined with Spray-Drying

Abstract

Well-shaped spherical agglomerates of FePO₄ particles were prepared by a novel method: chemical co-precipitation combined with spray-drying. Tap density analysis, Brunauer–Emmett–Teller analysis, characterizations of X-ray diffraction, scanning electron microscopy, and transmission electron microscopy confirmed that the micron-sized spherical agglomerates with high specific surface area and high tap density were composed of the uniform nano-sized particles. The effects of pH and reaction time on the morphology of the FePO₄ particles were investigated by experimental and theoretical analyses. The analyses revealed that amorphous FePO₄ was responsible for forming a well-shaped spherical agglomerate, and the ideal spherical particles were obtained at pH 3. The reaction time also played a significant role in controlling the size and surface morphology of the FePO₄ particles, and smooth spherical FePO₄ particles were obtained at a reaction time of 6 h. By this novel method, poly-porous spherical iron phosphate particles were prepared, which can be used with high efficiency in some special fields, especially as a precursor for synthesizing LiFePO₄ and catalysts.

Keywords

FePO₄ / Spherical agglomerate / Spray-drying / pH / Reaction time

References

[1] Mesko MG, Day DE, Bunker BC. Immobilization of CsCl and SrF₂ in iron phosphate glasses. Waste Manag, 2000, 20(4): 271-278.

[2] Balmér P, Frederiksen OF. A pilot-plant scale evaluation of potential precipitants in the secondary precipitation process. Water Res, 1975, 9(8): 721-727.

[3] Lazzarin P, Bellemo S. Fatigue strength of AISI304 and FePO₄ steels in the presence of circular notches. Lamiera, 1989, 26(10): 116-123.

[4] De Latour C. Magnetic separation in water pollution control. IEEE Trans Magn, 1973, 9(3): 314-316.

[5] Lai YM, Liang XF, Yang SY, et al. Raman and FTIR spectra of iron phosphate glasses containing cerium. J Mol Struct, 2011, 992(1–3): 84-88.

[6] Ye W, Otsuka K. Partial oxidation of ethane by reductively activated oxygen over iron phosphate catalyst. J Catal, 1997, 171(1): 106-114.

[7] Son D, Kim E, Kim TG, et al. Nanoparticle iron–phosphate anode material for Li-ion battery. Appl Phys Lett, 2004, 85(24): 5875-5877.

[8] Croce F, D’Epifanio A, Reale P, et al. Ruthenium oxide-added quartz iron phosphate as a new intercalation electrode in rechargeable lithium cells. J Electrochem Soc, 2003, 150(5): A576-A581.

[9] Xie HM, Wang RS, Ying JR, et al. Optimized LiFePO₄–polyacene cathode material for lithium-ion batteries. Adv Mater, 2006, 18(19): 2609-2613.

[10] Oh SW, Myung ST, Oh SM, et al. Polyvinylpyrrolidone-assisted synthesis of microscale C–LiFePO₄ with high tap density as positive electrode materials for lithium batteries. Electrochim Acta, 2010, 55(3): 1193-1199.

[11] Liu QB, Liao SJ, Song HY, et al. LiFePO₄/C microspheres with nano-micro structure, prepared by spray drying method assisted with PVA as template. Curr Nanosci, 2012, 8(2): 208-214.

[12] Yuan LX, Wang ZH, Zhang WX, et al. Goodenough development and challenges of LiFePO₄ cathode material for lithium-ion batteries. Energy Environ Sci, 2011, 4(2): 269-284.

[13] Tang XC, Li LX, Lai QL, et al. Investigation on diffusion behavior of Li⁺ in LiFePO₄ by capacity intermittent titration technique (CITT). Electrochim Acta, 2009, 54(8): 2329-2334.

[14] Gao F, Tang ZY, Xue JJ. Preparation and characterization of nano-particle LiFePO₄ and LiFePO₄/C by spray-drying and post-annealing method. Electrochim Acta, 2007, 53(4): 1939-1944.

[15] Yu DH, Qian JS, Xue NH, et al. Mesoporous nanotubes of iron phosphate: synthesis, characterization, and catalytic property. Langmuir, 2007, 23(2): 382-386.

[16] Wang Y, Wang XX, Su Z, et al. SBA-15-supported iron phosphate catalyst for partial oxidation of methane to formaldehyde. Catal Today, 2004, 93–95: 155-161.

[17] Yu F, Zhang JJ, Yang YF, et al. Porous micro-spherical aggregates of LiFePO₄/C nanocomposites: a novel and simple template-free concept and synthesis via sol–gel-spray drying method. J Power Sources, 2010, 195(19): 6873-6878.

[18] Yu F, Zhang JJ, Yang YF, et al. Preparation and characterization of mesoporous LiFePO₄/C microsphere by spray-drying assisted template method. J Power Sources, 2009, 189(1): 794-797.

[19] Nie YH, Carey JR, Chen JS. Physical and electrochemical properties of LiFePO₄/C composite cathode prepared from various polymer-containing precursors. J Power Sources, 2009, 193(2): 822-827.

[20] Mal NK, Bhaumik A, Matsukata M, et al. Syntheses of mesoporous hybridironoxophenyl phosphate, iron oxophosphate, and sulfonated oxophenyly phosphate. Ind Eng Chem Res, 2006, 45(23): 7748-7751.

[21] Kandori K, Kuwae T, Ishikawa T. Control on size and adsorptive properties of spherical ferric phosphate particles. J Colloid Interface Sci, 2006, 300(1): 225-231.

[22] Wang M, Xue YH, Zhang KL, et al. Synthesis of FePO₄·2H₂O nanoplates and their usage for fabricating superior high-rate performance LiFePO₄. Electrochim Acta, 2011, 56(11): 4294-4298.

[23] Ying JR, Lei M, Jiang CY, et al. Preparation and characterization of high-density spherical Li_0.97Cr_0.01FePO₄/C cathode material for lithium ion batteries. J Power Sources, 2006, 158(1): 543-549.

[24] Zhu YM, Tang SZ, Shi HH, et al. Synthesis of FePO₄·xH₂O for fabricating submicrometer structured LiFePO₄/C by a co-precipitation method. Ceram Int, 2014, 40(2): 2685-2690.

[25] Chen ZY, Zhu HL, Zhu W, et al. Electrochemical performance of carbon nanotube-modified LiFePO₄ cathodes for Li-ion batteries. Trans Nonferr Met Soc China, 2010, 20(4): 614-618.

[26] Zhao B, Jiang Y, Zhang HJ, et al. Morphology and electrical properties of carbon coated LiFePO₄ cathode materials. J Power Sources, 2009, 189(1): 462-466.

[27] Scaccia S, Carewska M, Prosini PP. Thermoanalytical study of iron(III) phosphate obtained by homogeneous precipitation from different media. Thermochim Acta, 2004, 413(1–2): 81-86.

[28] Wilhelmy RB, Matijević E. Preparation and growth kinetics of monodispersed ferric phosphate hydrosols. Colloids Surf, 1987, 22(2): 97-110.

[29] Stanislav K, Ladislav S. Handbook of chemical equilibria in analytical chemistry, 1985, Chichester: Ellis Horwood Limited.

[30] Gu YJ, Liu P, Chen YB, et al. Influence of pH on electrochemical performances of iron phosphate (FePO₄·xH₂O) particles and LiFePO₄/C composites. Adv Mater Res, 2013, 643: 100-103.

[31] Delacourt C, Wurm C, Reale P, et al. Low temperature preparation of optimized phosphates for Li-battery applications. Solid State Ion, 2004, 173(1–4): 113-118.

[32] Nielsen A. Kinetics of precipitation, 1964, New York: Pergamon Press.