A bi-functional Co–Ni layered double hydroxide three-dimensional porous array electrode derived from ZIF-L(Co)@ZIF-L(Co, Ni) for oxygen evolution reaction and supercapacitors. (19th April 2022)

• Record Type: Journal Article
• Authors: Chen, Chao; Deng, Xiaohua; Deng, Yingjie; An, Lu; Deng, Yijie; Zheng, Yuying; Dang, Dai; Yang, Xu
• Is Part Of: International journal of hydrogen energy. Volume 47:Number 33(2022)
• Page Start: 14896
• Page End: 14905
• Publication Date: 2022-04-19
• Subjects: Metal−organic framework -- Layered double hydroxide -- OER catalyst -- Supercapacitor; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2022.03.017
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: Developing high-efficiency bifunctional materials for electro-catalysis and supercapacitors are urgently needed but challenging. Herein, we develop a self-supporting Co–Ni LDH electrode prepared by in-situ growing ZIF-L(Co)@ZIF-L(Co, Ni) on carbon paper followed by a pseudomorphic transformation. The optimized Co–Ni LDH/carbon paper electrodes (CN-2/CP) exhibit excellent electrochemical activity and stability in oxygen evolution reactions (OER) and supercapacitors. The CN-2/CP electrode displays a low overpotential of 230 mV at 10 mA cm −2 and superior stability at 40-h chronopotentiometry for OER. For supercapacitor, the CN-2/CP electrode delivers a high specific capacitance of 1346 F g −1 at 1 A g −1 and maintains a capacitance of 88.5% after 7000 charge/discharge cycles at 20 A g −1 . Based on the physical and chemical characterization results, the high performance originates from the in-situ electrochemical conversion of metal hydroxide, improved conductivity, fast charge transfer at the interface and unique layered cross morphology providing more active sites. Graphical abstract: Image 1 Highlights: In-situ synthesis of Co–Ni LDH 3D porous array on carbon paper. The self-supported electrode exhibits high OER performance and stability. The large surface area and high porosity of CoNi LDH provide abundant active sites.