中文版 | English
CSpace
Zeolitic-imidazolate framework derived Ni-Co layered double hydroxide hollow microspheres with enhanced pseudocapacitive properties for hybrid supercapacitors
Li, Xu1,2; Liu, Shuangyi2; Bai, Sihan2; Li, Zhenhu2; Shen, Jun1
2022-04-21
摘要With the advantages of electrochemical activity for Ni and Co elements, as well as joint enhanced nature, layered double hydroxides (i.e., Ni-Co LDHs) are believed to be competitive candidates for hybrid supercapacitors (HSCs) but they possess poor structural stability. Here, a series of citrate-intercalated Ni-Co LDH electrode materials are synthesized by hydrolyzing ZIF-67 at room temperature. Due to three-carboxylic coordinate sites with metal hydroxide layers, citrate ions strongly support the layered structure as pillars and offer efficient enlarged interlayer paths for OH- transportation, resulting in an obviously enhanced utilization of the intrinsic properties of Ni-Co LDHs. In combination with the abundant active sites of hollow microsphere morphology, the electrochemical characteristics of Ni and Co elements are further determined, and thus, an evolution from typical pseudocapacitive to battery-type charge storing behaviors is first demonstrated. As a result, the Ni-Co-LDH-C-1:4 with a high Co content exhibits pseudocapacitive characteristics including high specific capacities of 135 and 124 mA h g(-1) at 1 and 10 A g(-1), and over 100% capacity retention after 10 000 charge-discharge cycles, showing excellent rate capability and cycling stability. Simultaneously, the Ni-Co-LDH-C-4:1 with a high Ni content demonstrates typical battery-type behavior with an obvious charge-discharge plateau and a maximum specific capacity of 255 mA h g(-1) (1835 F g(-1)) at 1 A g(-1), and good rate capability with 164 mA h g(-1) at 10 A g(-1). In addition, the hybrid electrode Ni-Co-LDH-M exhibits pseudocapacitance-like electrochemical characteristics due to the deliberate design of involving multiple compositions of Ni-Co-LDH-Cs, which is an anticipated property for battery-type electrodes to balance the dynamics of capacitive electrodes in HSCs. This method provides a route to design highly stable and activated pseudocapacitive electrodes for future-generation HSC applications.
DOI10.1039/d1tc05792h
发表期刊JOURNAL OF MATERIALS CHEMISTRY C
ISSN2050-7526
卷号10期号:16页码:6348-6357
通讯作者Li, Zhenhu(lizhenhu@cigit.ac.cn) ; Shen, Jun(shenjun@cqu.edu.cn)
收录类别SCI
WOS记录号WOS:000775153400001
语种英语