文献类型：期刊文献

英文题名：Spatially confined synthesis of a flexible and hierarchically porous three-dimensional graphene/FeP hollow nanosphere composite anode for highly efficient and ultrastable potassium ion storage

作者：Zhang, Zhifang[1];Wu, Chenxiao[1];Chen, Zhonghui[2];Li, Huiyu[1];Cao, Haijing[1];Luo, Xiaojing[1];Fang, Zebo[3];Zhu, Yanyan[1]

机构：[1]Shanghai Univ Elect Power, Coll Math & Phys, 2103 Pingliang Rd, Shanghai 200090, Peoples R China;[2]Henan Univ, Collaborat Innovat Ctr Nano Funct Mat & Applicat, Sch Mat Sci & Engn, Key Lab Special Funct Mat,Minist Educ, Kaifeng 475004, Peoples R China;[3]Shaoxing Univ, Dept Phys, Shaoxing 312000, Peoples R China

年份：2020

卷号：8

期号：6

起止页码：3369

外文期刊名：JOURNAL OF MATERIALS CHEMISTRY A

收录：SCI-EXPANDED(收录号：WOS:000521938400043)、、EI(收录号：20200808191168)、Scopus(收录号：2-s2.0-85079505094)、WOS

基金：We acknowledge the support by the National Natural Science Foundation of China (Grant No. 51672172, 51872186) and the start-up fund of Henan University for funding to Z.H.C. (CX3050A0920134).

语种：英文

外文关键词：Anodes - Graphene - Microphase separation - Nanospheres - Phosphorus compounds - Potassium - Stability - Transition metals

外文摘要：With excellent theoretical capacities, transition-metal phosphides (TMPs) have been recognized as promising anode materials for potassium-ion batteries (KIBs) but there remain considerable challenges in improving the structural stability and electrochemical performance. Moreover, the electrochemical reaction mechanism of TMP-based KIB anodes is still unclear and mostly unexplored. Herein, we elaborately design a flexible and hierarchically porous anode consisting of discrete FeP hollow nanospheres well encapsulated within a three-dimensional graphene skeleton (3DG/FeP) via a novel spatially confined one-step thermal transformation strategy using a 3DG/metal-organic framework (MOF) as the precursor for the first time. The unique architecture provides interconnected porous conducting network and tight contact between graphene and FeP hollow nanospheres as well as sufficient stress buffer nano-hollow spaces to greatly promote the charge transport and maintain the structural integrity. Thus, the 3DG/FeP anode delivers a high reversible capacity of 323 mA h g(-1) at 0.1 A g(-1) and ultrastable cycle performance with a capacity retention of 97.6% at 2 A g(-1) after 2000 cycles, which is almost the best result among all the reported FeP anodes for KIBs. Further detailed characterizations not only elucidate 3DG confinement-promoted microphase separation and nanoscale Kirkendall effects of MOF but also explore the multiple reversible intercalation and conversion processes of K+ insertion/extraction in the FeP component.