个人信息Personal Information
教授
博士生导师
硕士生导师
性别:女
毕业院校:大连理工大学
学位:博士
所在单位:医学部
学科:化学生物学. 药理学. 细胞生物学
办公地点:Chemical complex building,D513
联系方式:zczhang@dlut.edu.cn 13942696903
电子邮箱:zczhang@dlut.edu.cn
Highly stable lithium-sulfur batteries based on p-n heterojunctions embedded on hollow sheath carbon propelling polysulfides conversion
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论文类型:期刊论文
发表时间:2019-04-21
发表刊物:JOURNAL OF MATERIALS CHEMISTRY A
收录刊物:SCIE、EI
卷号:7
期号:15
页面范围:9230-9240
ISSN号:2050-7488
摘要:Newly-developed lithium-sulfur batteries (LSBs) have been supposed to be extremely promising devices as they deliver a high theoretical energy of 2600 W h kg(-1). Utilizing sulfur as the cathode material is advantageous due to its low price, non-toxicity, and abundant resources. The main bottleneck hindering the practical application of LSBs is their poor cycling performance due to the shuttling of soluble lithium polysulfides (LiPSs), poor conductivity, and sluggish redox reaction. Herein, we prepared a new type of p-n heterostructure embedded into carbon hollow nanosheet arrays grown on carbon cloth by subsequent sulfidation and nitridation. The hollow heterostructures can sufficiently restrict the dissolution of LiPSs due to the polar chemisorption and physical confinement, and facilitate polysulfide redox kinetics (Li2Sx Li2S, 2 x 8). The abundant active sites and boundary defects constructed by the Co9S8-Co4N heterostructures improve the nucleation/conversion redox kinetics of Li2S. Also, the hollow structure can increase the sulfur loading and supply enough space for relieving the volume expansion during the whole cycling process. After melting the diffused sulfur of the nanocomposites, the resulting free-standing S/CC@Co9S8-Co4N electrode exhibits a highly stable cycling rate with an ultralow capacity fading rate of 0.027% per cycle at 5.0C over 1000 cycles. Our work provides a potential avenue for constructing heterostructured materials for LSBs with high performance.