MOF-derived NiCo2S4 and carbon hybrid hollow spheres compactly concatenated by electrospun carbon nanofibers as self-standing electrodes for aqueous alkaline Zn batteries. Issue 8 (26th January 2022)

• Record Type: Journal Article
• Authors: Yu, Jiaqi; Cai, Daoping; Si, Junhui; Zhan, Hongbing; Wang, Qianting
• Is Part Of: Journal of materials chemistry. Volume 10:Issue 8(2022)
• Page Start: 4100
• Page End: 4109
• Publication Date: 2022-01-26
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/d1ta10597c
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : MOF-derived NiCo2 S4 nanoparticles and hollow carbon hybrid spheres compactly concatenated by electrospun carbon fibers have been successfully synthesized and employed as self-standing cathode electrodes for aqueous alkaline Zn batteries. Abstract : The development of high-performance cathode materials is of great importance for aqueous alkaline Zn batteries (AZBs) but also remains a great challenge. Herein, we demonstrate the rational design and synthesis of NiCo2 S4 nanoparticles and hollow carbon hybrid spheres compactly concatenated by carbon fibers (denoted as NiCo2 S4 /HCS@CFs) through an innovative combination of metal–organic framework (MOF)-derived strategy and electrospinning technique. The as-synthesized NiCo2 S4 /HCS@CF film is flexible, lightweight, and free of any polymer binders, which offers multilevel advantages including high electrical conductivity, abundant electroactive sites, fast ion diffusion, facile electrolyte permeability and robust structural stability. When evaluated as self-standing cathode electrodes, as expected, the resulting NiCo2 S4 /HCS@CFs//Zn batteries exhibit an extremely high capacity of 343.1 mA h g −1 at a current density of 3.8 A g −1 (based on the NiCo2 S4 active material), as well as superior rate performance and decent cycling performance. Moreover, the corresponding quasi-solid-state batteries are also fabricated to confirm the potential for practical applications. Remarkably, the energy densities of NiCo2 S4 /HCS@CFs//Zn batteries are 563.2 W h kg −1 and 49.1 mW h cm −3 (liquid) and 504.1 W h kg −1 and 43.9 mW h cm −3 (quasi-solid-state). What's more, density functional theory (DFT) calculations reveal that NiCo2 S4 /HCS@CFs have strong adsorption ability for OH − ions. This work not only highlights the importance of developing advanced flexible and lightweight cathode electrodes for aqueous AZBs, but also provides some insights into electrode designs for other energy storage devices.