Tempura-like carbon/carbon composite as advanced anode materials for K-ion batteries

• 作者: Hao-Jie Liang Zhen-Yi Gu Xue-Ying Zheng Wen-Hao Li Ling-Yun Zhu Zhong-Hui Sun Yun-Feng Meng Hai-Yue Yu Xian-Kun Hou Xing-Long Wu
• 来源期刊: 能源化学
• 年，卷（期）: 2021,（8）
• 页码范围: 589-598
• 页数: 10页
• 语种: 英文

摘要

Graphite as a promising anode candidate of K-ion batteries (KIBs) has been increasingly studied currently,but corresponding rate performance and cycling stability are usually inferior to amorphous carbon materials.To protect the layer structure and further boost performance,tempura-like carbon/carbon nanocomposite of graphite@pitch-derived S-doped carbon (G@PSC) is designed and prepared by a facile and low-temperature modified molten salt method.This robust encapsulation structure makes their respective advantages complementary to each other,showing mutual promotion of electrochemical performances caused by synergy effect.As a result,the G@PSC electrode is applied in KIBs,delivering impressive rate capabilities (465,408,370,332,290,and 227 mA h g-1 at 0.05,0.2,0.5,1,2,and 5 A g-1) and ultralong cyclic stability (163 mA g-1 remaining even after 8000 cycles at 2 A g-1).On basis of ex-situ studies,the sectionalized K-storage mechanism with adsorption (pseudocapacitance caused by S doping)-intercalation (pitch-derived carbon and graphite) pattern is revealed.Moreover,the exact insights into remarkable rate performances are taken by electrochemical kinetics tests and density functional theory calculation.In a word,this study adopts a facile method to synthesize high-performance carbon/carbon nanocomposite and is of practical significance for development of carbonaceous anode in KIBs.