Sulfur-doped 3D hierarchical porous carbon network toward excellent potassium-ion storage performance  

作　　者：Dan Wang Kang-Hui Tian Jie Wang Zhi-Yuan Wang Shao-Hua Luo Yan-Guo Liu Qing Wang Ya-Hui Zhang Ai-Min Hao Ting-Feng Yi 

机构地区：[1]School of Materials Science and Engineering,Northeastern University,Shenyang 110819,China [2]Key Laboratory of Dielectric,Electrolyte Functional Materia-Hebei Province,Qinhuangdao 066004,China [3]School of Resources and Materials,Northeastern University,Qinhuangdao 066004,China

出　　处：《Rare Metals》2021年第9期2464-2473,共10页稀有金属（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(Nos.51871046,51902046,52071073,51874079,51571054,51771046 and 51674068);the Natural Science Foundation of Liaoning Province(No.201602257);the Natural Science Foundation of Hebei Province(Nos.E2019501097,E2018501091 and E2020501004);the Science and Technology Project of Hebei Province(No.15271302D);the Training Foundation for Scientific Research of Talents Project Hebei Province(No.A2016005004);the Young Talents Program in University of Hebei Province(No.BJ2018014);Hebei Province Higher Education Science and Technology Research Project(No.QN2017103);the Fundamental Research Funds for the Central Universities(Nos.N182304017,N182304015,N172302001 and N172304044)。

摘　　要：Carbonaceous materials are promising anode candidates for potassium-ion batteries, but currently the unsatisfactory cycling and rate performances due to the sluggish diffusion kinetic and serious structure damage during K+ insertion/extraction limit their practical application. Herein, a series of sulfur-doped porous carbons(SPCs) were prepared via a template-assisted freeze-drying followed by the carbonization and sulfuration processes at different temperatures. Among the three as-synthesized samples, SPC-600 exhibits the highest specific capacity(407 mAh·g^(-1) at 0.10 A·g^(-1)), the best rate(242 mAh·g^(-1) at 2.00 A·g^(-1)) and cycling performance(286 m Ah·g^(-1) after 800 cycles at 0.50 A·g^(-1)). All the SPCs display higher capacities than the undoped carbon materials. The excellent electrochemical performance of SPC can be ascribed to the abundant three-dimensional porous structure together with S-doping in the disordered carbon, which is favor of providing adequate reaction active sites as well as fast ion/electron transport paths. The density functional theory(DFT) calculations further demonstrate that the sulfurdoping can promote K-ion adsorption and storage. Meanwhile, the kinetic analyses reveal that surface-induced capacitive mechanism dominates the K-ion storage process in SPCs, which contributes to ultrafast charge storage. This work provides an effective strategy for fabricating highperformance potassium-ion storage electrode materials.

关 键 词：Potassium-ion batteries Porous carbon Sulfur-doping Density functional theory(DFT)calculations 

分 类 号：TM912[电气工程—电力电子与电力传动]