A carbon cloth interlayer immobilizes carbon nanotube-supported ternary chalcogen compounds in novel lithium-chalcogenide batteries. (20th December 2022)

• Record Type: Journal Article
• Authors: Yang, Zewen; Jia, Dandan; Zhao, Qing; Song, Depeng; Sun, Xiaolin; Zhang, Yuan; Gao, Jing; Ohsaka, Takeo; Matsumoto, Futoshi; Shen, Qiang; Wu, Jianfei
• Is Part Of: Electrochimica acta. Volume 436(2022)
• Publication Date: 2022-12-20
• Subjects: Lithium-chalcogenide batteries -- Multichalcogen active material -- Carbon nanotubes -- Carbon cloth interlayer -- Performance enhancement; SST811 multichalcogen active material composed of S, Se, and Te in a ratio of 8:1:1 -- CNT multiwalled carbon nanotubes -- CCNT carboxylated multiwalled carbon nanotubes -- CC carbon cloth; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2022.141465
• Languages: English
• ISSNs: 0013-4686

Abstract

Highlights: CCNT contains oxygen-containing functional groups with high electronegativity. The reaction mechanism of SST811/CCNT was deeply explored. The introduction of a CC interlayer can effectively enhance the performance. SST811/CCNT cathode maintained 1219.2 mAh g −1 after 300 cycles with interlayer. CC interlayer does not affect the intrinsic reaction mechanism of SST811/CCNT. Abstract: The development of lithium-chalcogen batteries containing one active species is limited by bottlenecks. Multichalcogen composites that integrate the advantages of each component while avoiding their defects are desired. Herein, carbon nanotubes (CNT) and carboxylated-CNT (CCNT) are adopted as carriers for active substances consisting of S, Se, and Te at a feed ratio of 8:1:1 (SST811). The electrochemical performance of SST811/CCNT is better than that of SST811/CNT because CCNT contains more oxygen-containing functional groups, allowing the active species to be firmly anchored. Cyclic voltammetry (CV) curves, charge-discharge profiles and in-situ Raman results reveal the solid-phase charge-discharge mechanism of SST811/CCNT in ester electrolyte, consisting of a combination of basic reaction steps. To suppress the shedding of active species during long cycling, a carbon cloth (CC) interlayer is introduced between cathode and separator without altering the inherent reaction mechanism of SST811/CCNT. Under the protection of CC interlayer, the capacity of SST811/CCNT remains at 1219.2 mAh g −1 after 300 cycles, which is 1.5 times that without interlayer. The protective effect of CC interlayer is demonstrated by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), X-ray diffraction (XRD), and Raman results. This work inspires the further development of lithium-chalcogenide batteries. Graphical abstract: Carboxylated carbon nanotubes containing oxygen-containing functional groups with high electronegativity inevitably cannot firmly immobilize the S-Se-Te ternary active species in long-term continuous reactions. The introduction of a carbon cloth protective interlayer can refix the active species that have fallen off without affecting the inherent reaction mechanism, thereby improving the cycling stability. Image, graphical abstract