"Ship in a Bottle" design of ZIF-9@CoAl LDH hybrid compound as a high performance asymmetric supercapacitor. (28th April 2020)

• Record Type: Journal Article
• Authors: Wang, Guorong; Li, Yanbing; Jin, Zhiliang
• Is Part Of: New journal of chemistry. Volume 44:Number 18(2020)
• Page Start: 7528
• Page End: 7540
• Publication Date: 2020-04-28
• Subjects: Chemistry -- Periodicals; Chimie -- Périodiques; 540
• DOI: 10.1039/d0nj00611d
• Languages: English
• ISSNs: 1144-0546

Abstract

Abstract : The ZIF-9@CoAl LDH compound was successfully synthesized by a "Ship in a Bottle" method. The conductivity of CoAl LDHs was improved by the introduction of 2D ZIF-9 micro-slices. Abstract : Constructing a particular nanostructure and improving electrical conductivity are two effective ways to improve the charge storage of LDH-based electrode materials. An asymmetric supercapacitor coupled with double-layer capacitance materials is the most promising strategy to improve the performance of a supercapacitor device. In this study, the ZIF-9@CoAl LDH compound was successfully synthesized by a "Ship in a Bottle" method. The conductivity of CoAl LDHs was improved by the introduction of 2D ZIF-9 micro-slices. The ZIF-9@CoAl LDH hybrid structure exhibited a high specific capacitance of 702.7 F g −1 at 1 A g −1 compared with that of the pure CoAl LDHs of 518.7 F g −1 at 1 A g −1 and recorded a favorable rate capability of 73.8% when the current density is up to 20 A g −1 (56.1% of pure CoAl LDHs). Besides, the assembled ZIF-9@CoAl LDHs//activated carbon asymmetric supercapacitor cell device worked synergistically to achieve a high energy density of 32.1 W h kg −1 with a power density of 1000 W kg −1 and a capacity retention of 75% after 5000 cycles. This work provides a simple strategy to improve the rate capability and energy storage performance of LDH-based materials.