title: Enhanced Electrochemical Performance of Layered Lithium-Rich Cathode Materials by Constructing Spinel-Structure Skin and Ferric Oxide Islands.
abstract: Layered lithium-rich cathode materials have been considered as competitive candidates for advanced lithium-ion batteries because they are environmentally benign, high capacity (more than 250 mAh·g-1), and low cost. However, they still suffer from poor rate capability and modest cycling performance. To address these issues, we have proposed and constructed a spinel-structure skin and ferric oxide islands on the surface of layered lithium-rich cathode materials through a facile wet chemical method. During the surface modification, Li ions in the surface area of pristine particles could be partially extracted by H+, along with the depositing process of ferric hydrogen. After calcination, the surface structure transformed to spinel structure, and ferric hydrogen was oxidized to ferric oxide. The as-designed surface structure was verified by EDX, HRTEM, XPS, and CV. The experimental results demonstrated that the rate performance and capacity retentions were significantly enhanced after such surface modification. The modified sample displayed a high discharge capacity of 166 mAh·g-1at a current density of 1250 mA·g-1and much more stable capacity retention of 84.0% after 50 cycles at 0.1C rate in contrast to 60.6% for pristine material. Our surface modification strategy, which combines the advantages of spinel structure and chemically inert ferric oxide nanoparticles, has been shown to be effective for realizing the layered lithium-rich cathodes with surface construction of fast ion diffusing capability as well as robust electrolyte corroding durability.
authors.affiliation: School of Material Science and Engineering, Beijing Key Laboratory of Environmental Science and Engineering, Beijing Institute of Technology , Beijing 100081, China.|Collaborative Innovation Center for Electric Vehicles in Beijing, Beijing 100081, China.|National Development Center of High Technology Green Materials, Beijing 100081, China.
authors.forename: Shi
authors.initials: S
authors.lastname: Chen
authors.affiliation: School of Material Science and Engineering, Beijing Key Laboratory of Environmental Science and Engineering, Beijing Institute of Technology , Beijing 100081, China.|National Development Center of High Technology Green Materials, Beijing 100081, China.
authors.forename: Yu
authors.identifier: http://orcid.org/0000-0001-7808-8004
authors.initials: Y
authors.lastname: Zheng
authors.affiliation: School of Material Science and Engineering, Beijing Key Laboratory of Environmental Science and Engineering, Beijing Institute of Technology , Beijing 100081, China.|National Development Center of High Technology Green Materials, Beijing 100081, China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Lu
authors.affiliation: School of Material Science and Engineering, Beijing Key Laboratory of Environmental Science and Engineering, Beijing Institute of Technology , Beijing 100081, China.|Collaborative Innovation Center for Electric Vehicles in Beijing, Beijing 100081, China.|National Development Center of High Technology Green Materials, Beijing 100081, China.
authors.forename: Yuefeng
authors.identifier: http://orcid.org/0000-0002-5144-2832
authors.initials: Y
authors.lastname: Su
authors.affiliation: School of Material Science and Engineering, Beijing Key Laboratory of Environmental Science and Engineering, Beijing Institute of Technology , Beijing 100081, China.|National Development Center of High Technology Green Materials, Beijing 100081, China.
authors.forename: Liying
authors.initials: L
authors.lastname: Bao
authors.affiliation: School of Material Science and Engineering, Beijing Key Laboratory of Environmental Science and Engineering, Beijing Institute of Technology , Beijing 100081, China.
authors.forename: Ning
authors.initials: N
authors.lastname: Li
authors.affiliation: School of Material Science and Engineering, Beijing Key Laboratory of Environmental Science and Engineering, Beijing Institute of Technology , Beijing 100081, China.
authors.forename: Yitong
authors.initials: Y
authors.lastname: Li
authors.affiliation: School of Material Science and Engineering, Beijing Key Laboratory of Environmental Science and Engineering, Beijing Institute of Technology , Beijing 100081, China.|Collaborative Innovation Center for Electric Vehicles in Beijing, Beijing 100081, China.|National Development Center of High Technology Green Materials, Beijing 100081, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.affiliation: School of Material Science and Engineering, Beijing Key Laboratory of Environmental Science and Engineering, Beijing Institute of Technology , Beijing 100081, China.|Collaborative Innovation Center for Electric Vehicles in Beijing, Beijing 100081, China.|National Development Center of High Technology Green Materials, Beijing 100081, China.
authors.forename: Renjie
authors.identifier: http://orcid.org/0000-0002-7001-2926
authors.initials: R
authors.lastname: Chen
authors.affiliation: School of Material Science and Engineering, Beijing Key Laboratory of Environmental Science and Engineering, Beijing Institute of Technology , Beijing 100081, China.|Collaborative Innovation Center for Electric Vehicles in Beijing, Beijing 100081, China.|National Development Center of High Technology Green Materials, Beijing 100081, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Wu
keywords: ferric oxide; layered lithium-rich cathode material; lithium-ion batteries; spinel structure; surface modification