Highly Reversible Li–Se Batteries with Ultra-Lightweight N,S-Codoped Graphene Blocking Layer

作     者：Xingxing Gu Lingbao Xin Yang Li Fan Dong Min Fu Yanglong Hou 

作者机构：Chongqing Key Laboratory of Catalysis and New Environmental Materials College of Environment and Resources Chongqing Technology and Business University School of Chemical Engineering Shandong University of Technology College of Arts Chongqing Technology and Business University Beijing Key Laboratory for Magnetoelectric Materials and Devices (BKLMMD) BIC-ESAT Department of Materials Science and Engineering College of Engineering Peking University 

出 版 物：《Nano-Micro Letters》 (纳微快报（英文版）)

年 卷 期：2018年第10卷第4期

页      面：42-51页

核心收录：

学科分类：081702[工学-化学工艺] 0808[工学-电气工程] 08[工学] 0817[工学-化学工程与技术] 

基　　金：supported by the National Natural Science Foundation of China (51125001,51172005) the NSFCRGC Joint Research Scheme (51361165201) the Start-up Foundation of High-level Talents in Chongqing Technology and Business University (1856008) 

主　　题：Li–Se batteries N,S-codoped Graphene Ultra-lightweight Free-standing Vacuum filtration 

摘      要：The desire for practical utilization of rechargeable lithium batteries with high energy density has motivated attempts to develop new electrode materials and battery systems. Here, without additional binders we present a simple vacuum filtration method to synthesize nitrogen and sulfur codoped graphene(N,S-G) blocking layer, which is ultra-lightweight, conductive, and free standing. When the N,S-G membrane was inserted between the catholyte and separator, the lithium–selenium(Li–Se)batteries exhibited a high reversible discharge capacity of 330.7 mAh g^(-1) at 1 C(1 C = 675 mA g^(-1)) after 500 cycles and high rate performance(over 310 mAh g^(-1) at 4 C) even at an active material loading as high as ～5 mg cm^(-2). This excellent performance can be ascribed to homogenous dispersion of the liquid active material in the electrode, good Li^+-ion conductivity, fast electronic transport in the conductive graphene framework, andstrong chemical confinement of polyselenides by nitrogen and sulfur atoms. More importantly, it is a promising strategy for enhancing the energy density of Li–Se batteries by using the catholyte with a lightweight heteroatom doping carbon matrix.