| Title | Carbon-coated ultrathin metallic V5Se8 nanosheet for high-energy-density and robust potassium storage |
| Authors | Yang, Chao Lv, Fan Dong, Kang Lai, Feili Zhao, Kangning Sun, Fu Dou, Shuming Wang, Qian Xu, Jie Zhang, Panpan Arlt, Tobias Chen, Xiaodong Chen, Yanan Manke, Ingo Guo, Shaojun |
| Affiliation | Tech Univ Berlin, Inst Mat Sci & Technol, Str 17 Juni 135, D-10623 Berlin, Germany Helmholtz Ctr Berlin Mat & Energy, Hahn Meitner Pl 1, D-14109 Berlin, Germany Peking Univ, Dept Mat Sci & Engn, Coll Engn, Beijing 100871, Peoples R China Tianjin Univ, Sch Mat Sci & Engn, Tianjin 300350, Peoples R China Chinese Acad Sci, Qingdao Inst Bioenergy & Bioproc Technol, Qingdao 266101, Peoples R China Katholieke Univ Leuven, Dept Chem, Celestijnenlaan 200F, B-3001 Leuven, Belgium Shanghai Univ, Inst Sustainable Energy, Coll Sci, 99 Shangda Rd, Shanghai 200444, Peoples R China Xi An Jiao Tong Univ, Sch Sci, Dept Appl Chem, Xian 710049, Peoples R China Univ Adelaide, Sch Chem Engn, Adelaide, SA 5005, Australia |
| Issue Date | Mar-2021 |
| Publisher | ENERGY STORAGE MATERIALS |
| Abstract | Earth-abundant potassium is a promising alternative to lithium in energy-storage systems, but a pivotal limitation of potassium-ion batteries (KIBs) is their relatively low capacity and inferior cycle stability. Here we report the first synthesis of ultrathin metallic V5Se8 nanosheets embedded in porous carbon (graphene-like V5Se8@C) as a superior anode for KIBs, which achieves a high reversible depotassiation capacity along with unprecedented rate performance and outstanding cycling stability (a reversible depotassiation capacity of 145 mAh g(-1) after 800 cycles at 4 A g(-1) with 82.9% capacity retention). The impressive performances achieved are attributed to the synergistic contributions of the NiAs-type superstructure, ultrathin nanosheet architecture, sufficient accessible active sites, multi-dimensional electronic/ionic transport pathways and significant pseudocapacitive behaviors. Combined experimental analysis and first-principles calculations reveal fast reaction kinetics, high ionic/electronic conductivity and low diffusion barriers of K-ion in graphene-like V5Se8 @C hybrid. Ex-situ characterizations confirm that V5Se8@C electrode undergo a reversible phase-evolution by the sequential intercalation and conversion reactions with synergistic K+-storage mechanisms. Furthermore, by coupling with pre-treated K0.5MnO2 cathode, the full-cell is demonstrated to exhibit large energy density of 160.2 Wh kg(-1) with average discharge voltage of 2.2 V and capacity retention of 86% over 200 cycles. These desirable findings demonstrate graphene-like V5Se8@C nanosheets hold great practical application in future grid-scale energy storage. |
| URI | http://hdl.handle.net/20.500.11897/605770 |
| ISSN | 2405-8297 |
| DOI | 10.1016/j.ensm.2020.11.005 |
| Indexed | SCI(E) |
| Appears in Collections: | 工学院 |
