title: Synthesis of lithium iron phosphate/carbon microspheres by using polyacrylic acid coated iron phosphate nanoparticles derived from iron(III) acrylate.
abstract: Lithium iron phosphate/carbon (LiFePO4 /C) microspheres with high rate and cycling performance are synthesized from iron phosphate/polyacrylic acid (FePO4 /PAA) nanoparticles. Iron(III) acrylate is used as a precursor for both the iron and carbon sources. FePO4 nanoparticles are first produced by a coprecipitation reaction. The byproduct, acrylic acid ions, is polymerized in situ to form a uniform PAA layer on the surface of the FePO4 nanoparticles. The as-prepared LiFePO4 /C microspheres are composed of primary nanoparticles with sizes of 40-50 nm. The nanoparticles are fully coated with a thin, uniform carbon layer derived from the decomposition of the PAA layer. The uniform carbon-coating layer cooperates with interstitial and boundary carbon derived from sucrose successfully to construct an excellent interconnecting conductive network in the microspheres. As a result of the unique structure, the as-prepared LiFePO4 /C microspheres display both high electronic and ionic conductivities, which contribute to their high rate performance (162.9 mAh g(-1) at 0.1C and 126.1 mAh g(-1) at 5C) and excellent cycling stability (97.1% of capacity retention after 500 cycles at 5C/5C).
authors.affiliation: Engineering Laboratory for the Next Generation Power and Energy Storage Batteries, and Engineering Laboratory for Functionalized Carbon Materials, Graduate School at Shenzhen, Tsinghua University, Shenzhen, 518055 (P.R. China); Laboratory of Advanced Materials, School of Materials Science and Engineering, Tsinghua University, Beijing, 100084 (P.R. China).
authors.forename: Dongwei
authors.initials: D
authors.lastname: Xu
authors.forename: Yan-Bing
authors.initials: YB
authors.lastname: He
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Chu
authors.forename: Zhaojun
authors.initials: Z
authors.lastname: Ding
authors.forename: Baohua
authors.initials: B
authors.lastname: Li
authors.forename: Jianfu
authors.initials: J
authors.lastname: He
authors.forename: Hongda
authors.initials: H
authors.lastname: Du
authors.forename: Xianying
authors.initials: X
authors.lastname: Qin
authors.forename: Feiyu
authors.initials: F
authors.lastname: Kang
mesh_terms: D000179:Acrylates / Q000737:chemistry; D000180:Acrylic Resins / Q000737:chemistry*; D002244:Carbon / Q000737:chemistry*; D060326:Chemistry Techniques, Synthetic; D004553:Electric Conductivity; D005290:Ferric Compounds / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D008094:Lithium / Q000737:chemistry*; D008863:Microspheres; D008958:Models, Molecular; D008968:Molecular Conformation; D053758:Nanoparticles / Q000737:chemistry*; D010710:Phosphates / Q000138:chemical synthesis* / Q000737:chemistry*
chemical_list: D000179:Acrylates; D000180:Acrylic Resins; D005290:Ferric Compounds; C473349:LiFePO4; D010710:Phosphates; C006903:carbopol 940; D002244:Carbon; D008094:Lithium; D007501:Iron; C036658:acrylic acid; C035885:ferric phosphate
keywords: carbon; electrochemistry; lithium; nanoparticles; polymers