title: Nitrogen-Doped Yolk-Shell-Structured CoSe/C Dodecahedra for High-Performance Sodium Ion Batteries.
abstract: In this work, nitrogen-doped, yolk-shell-structured CoSe/C mesoporous dodecahedra are successfully prepared by using cobalt-based metal-organic frameworks (ZIF-67) as sacrificial templates. The CoSe nanoparticles are in situ produced by reacting the cobalt species in the metal-organic frameworks with selenium (Se) powder, and the organic species are simultaneously converted into nitrogen-doped carbon material in an inert atmosphere at temperatures between 700 and 900 °C for 4 h. For the composite synthesized at 800 °C, the carbon framework has a relatively higher extent of graphitization, with high nitrogen content (17.65%). Furthermore, the CoSe nanoparticles, with a size of around 15 nm, are coherently confined in the mesoporous carbon framework. When evaluated as novel anode materials for sodium ion batteries, the CoSe/C composites exhibit high capacity and superior rate capability. The composite electrode delivers the specific capacities of 597.2 and 361.9 mA h g-1at 0.2 and 16 A g-1, respectively.
authors.affiliation: School of Materials Science & Engineering, Central South University , Changsha 410083, Hunan China.
authors.forename: Yifang
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: School of Materials Science & Engineering, Central South University , Changsha 410083, Hunan China.
authors.forename: Anqiang
authors.identifier: http://orcid.org/0000-0002-7605-1192
authors.initials: A
authors.lastname: Pan
authors.affiliation: School of Materials Science & Engineering, Central South University , Changsha 410083, Hunan China.
authors.forename: Lin
authors.initials: L
authors.lastname: Ding
authors.affiliation: School of Resources & Safety Engineering, Central South University , Changsha 410083, Hunan China.
authors.forename: Zilong
authors.initials: Z
authors.lastname: Zhou
authors.affiliation: School of Materials Science & Engineering, Central South University , Changsha 410083, Hunan China.
authors.forename: Yaping
authors.initials: Y
authors.lastname: Wang
authors.affiliation: School of Materials Science & Engineering, Central South University , Changsha 410083, Hunan China.
authors.forename: Shaoyu
authors.initials: S
authors.lastname: Niu
authors.affiliation: School of Materials Science & Engineering, Central South University , Changsha 410083, Hunan China.
authors.forename: Shuquan
authors.initials: S
authors.lastname: Liang
authors.affiliation: Department of Materials Science & Engineering, University of Washington , Seattle, Washington 98195, United States.
authors.forename: Guozhong
authors.identifier: http://orcid.org/0000-0003-1498-4517
authors.initials: G
authors.lastname: Cao
keywords: anode; cobalt selenide; metal−organic frameworks; nitrogen-doped carbon; sodium ion batteries