title: Controlled synthesis of series NixCo3-xO4 products: Morphological evolution towards quasi-single-crystal structure for high-performance and stable lithium-ion batteries.
abstract: Transition metal oxides are very promising alternative anode materials for high-performance lithium-ion batteries (LIBs). However, their conversion reactions and concomitant volume expansion cause the pulverization, leading to poor cycling stability, which limit their applications. Here, we present the quasi-single-crystal Ni(x)Co(3-x)O4 hexagonal microtube (QNHM) composed of continuously twinned single crystal submicron-cubes as anode materials for LIBs with high energy density and long cycle life. At the current density of 0.8 A g(-1), it can deliver a high discharge capacities of 1470 mAh g(-1) over 100 cycles (105% of the 2nd cycle) and 590 mAh g(-1) even after 1000 cycles. To better understand what underlying factors lead our QNHMs to achieve excellent electrochemical performance, a series of Ni(x)Co(3-x)O4 products with systematic shape evolution from spherical to polyhedral, and cubic particles as well as circular microtubes consisted of spheres and square microtubes composed of polyhedra have been synthesized. The excellent electrochemical performance of QNHMs is attributed to the unique stable quasi-single-crystal structure, which can both provide efficient electrical transport pathway and suppress the electrode pulverization. It is important to note that such quasi-single-crystal structure would be helpful to explore other high-energy lithium storage materials based on alloying or conversion reactions.
authors.affiliation: School of Physics and Engineering, State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-sen University, Guangzhou 510275, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: School of Physics and Engineering, State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-sen University, Guangzhou 510275, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Instrumental Analysis &Research Center, Sun Yat-sen University, Guangzhou 510275, China.
authors.forename: Wenxia
authors.initials: W
authors.lastname: Zhao
authors.affiliation: Key Laboratory of New Processing Technology for Nonferrous Metal and Materials, Ministry of Education, Guilin University of Technology, Guilin, 541004, China.
authors.forename: Hai
authors.initials: H
authors.lastname: Wang
authors.affiliation: School of Physics and Engineering, State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-sen University, Guangzhou 510275, China.
authors.forename: Baojun
authors.initials: B
authors.lastname: Li
authors.affiliation: School of Physics and Engineering, State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-sen University, Guangzhou 510275, China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Zhou
authors.affiliation: School of Physics and Engineering, State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-sen University, Guangzhou 510275, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Shen