title: High-Rate LiTi2(PO4)3@N-C Composite via Bi-nitrogen Sources Doping.
abstract: Mesoporous LiTi2(PO4)3@nitrogen-rich doped carbon composites have been synthesized by a novel bi-nitrogen sources doping strategy. Tripolycyanamide (C3H6N6) and urea are proposed for the first time as both nitrogen and carbon sources to achieve a homogeneous nitrogen-doped carbon coating layer via an in situ method. The electrode delivers ultrahigh rate performance and outstanding cycling stability in lithium ion batteries (LIBs). In an organic electrolyte system, the electrode demonstrates high discharge capacities of 120 mAh g(-1) and 87 mAh g(-1) at 20C and 50C, respectively. Moreover, 89.5% of initial discharge capacity is retained after 1000 cycles at 10C. When used as an anode for aqueous LIBs, the electrode also demonstrates superior rate capability with the discharge capacity of 103 mAh g(-1) at 10C, corresponding to 84% of that at 1C. Outstanding cycling stability with capacity retention of 91.2% after 100 cycles at 30 mA g(-1) and 90.4% over 400 cycles at 150 mA g(-1) are also demonstrated. The uniform nitrogen-rich carbon coating and unique mesoporous structure play important roles in effectively suppressing the charge-transfer resistance and facilitating Li ion/electron diffusion, thus leading to the superior electrochemical properties.
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University , Changsha, 410083, People's Republic of China.
authors.forename: Dan
authors.initials: D
authors.lastname: Sun
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University , Changsha, 410083, People's Republic of China.
authors.forename: Xia
authors.initials: X
authors.lastname: Xue
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University , Changsha, 410083, People's Republic of China.
authors.forename: Yougen
authors.initials: Y
authors.lastname: Tang
authors.affiliation: Department of Electrical and Computer Engineering, University of Houston , Houston, Texas 77204, United States.
authors.forename: Yan
authors.initials: Y
authors.lastname: Jing
authors.affiliation: Department of Materials Science & Engineering, University of Washington , Seattle, Washington 98185, United States.
authors.forename: Bin
authors.initials: B
authors.lastname: Huang
authors.affiliation: Battery Materials, BASF (China) Co., Ltd. , Shanghai, 201206, People's Republic of China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Ren
authors.affiliation: Department of Electrical and Computer Engineering, University of Houston , Houston, Texas 77204, United States.
authors.forename: Yan
authors.initials: Y
authors.lastname: Yao
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University , Changsha, 410083, People's Republic of China.|State Key Laboratory for Powder Metallurgy, Central South University , Changsha 410083, People's Republic China.
authors.forename: Haiyan
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Materials Science & Engineering, University of Washington , Seattle, Washington 98185, United States.
authors.forename: Guozhong
authors.initials: G
authors.lastname: Cao
keywords: aqueous lithium ion battery; cycling performance; mesoporous LiTi2(PO4)3/C; nitrogen doping; rate performance