N,P-codoped porous carbon derived from chitosan with hierarchical N-enriched structure and ultra-high specific surface Area toward high-performance supercapacitors  

作　　者：Xipeng Xin Na Song Ruiming Jia Bingnan Wang Hongzhou Dong Shuai Ma Lina Sui Yingjie Chen Qian Zhang Lifeng Dong Liyan Yu 

机构地区：[1]College of Materials Science and Engineering,Qingdao University of Science and Technology,Qingdao,266042,China [2]School of Mathematics and Physics,Qingdao University of Science and Technology,Qingdao,266042,China

出　　处：《Journal of Materials Science & Technology》2021年第29期45-55,共11页材料科学技术（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(Nos.21776147,21606140,61604086,and 21905153);the Qingdao Municipal Science and Technology Bureau,China(19-6-1-91-nsh);the International Science&Technology Cooperation Program of China(No.2014DFA60150);the Department of Science and Technology of Shandong Province(Nos.ZR2018BB066 and 2016GGX104010);the Chemcloudcomputing of National Supercomputing Center in Shenzhen(Shenzhen CloudComputing Center)。

摘　　要：In this work,a facile"carbonization-activation"strategy is developed to synthesize N,P-codoped hierarchical porous carbon.Phosphoric acid is innovatively introduced during the hydrothermal process to achieve in-situ P doping as well as create abundant pores,and the employment of sodamide is of vital importance to simultaneously serve as activating agent and N-source to succeed a high-level N doping.Thus,the obtained samples exhibit a unique three-dimensional hierarchical structure with an ultra-high specific surface area(3646 m^(2)g^(-1))and ultra-high N-doping level(9.81 at.%).Computational analyses confirm that N,P co-doping and higher N content can enhance active sites and widen potential differences of carbon materials to improve their capacitance.The as-prepared carbon materials demonstrate superior electrochemical performances,such as an ultra-high capacitance of 586 Fg^(-1)at 1 Ag^(-1),a superior rate capability of 409 Fg^(-1)at 20 Ag^(-1),and excellent long-term stability of 97%capacitance retention after10,000 cycles in 6 M KOH.Moreover,an assembled symmetric supercapacitor delivers a high energy density of 28.1 Wh kg^(-1)at the power density of 450 W kg^(-1)in 1 M Na_(2)SO_(4),demonstrating a great potential for applications in supercapacitors.

关 键 词：facile and cost-effective strategy Ultra-high specific surface area High-level heteroatoms doping High specific capacitance 

分 类 号：TQ127.11[化学工程—无机化工] TM53[电气工程—电器]