Enabling Flexible Heterostructures for Li‐Ion Battery Anodes Based on Nanotube and Liquid‐Phase Exfoliated 2D Gallium Chalcogenide Nanosheet Colloidal Solutions. Issue 34 (10th July 2017)

• Record Type: Journal Article
• Authors: Zhang, Chuanfang (John); Park, Sang‐Hoon; Ronan, Oskar; Harvey, Andrew; Seral‐Ascaso, Andrés; Lin, Zifeng; McEvoy, Niall; Boland, Conor S.; Berner, Nina C.; Duesberg, Georg S.; Rozier, Patrick; Coleman, Jonathan N.; Nicolosi, Valeria
• Is Part Of: Small. Volume 13:Issue 34(2017)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2017-07-10
• Subjects: chalcogenides -- in situ XRD -- Li‐ion battery -- liquid‐phase exfoliation -- percolated networks; Nanotechnology -- Periodicals; Nanoparticles -- Periodicals; Microtechnology -- Periodicals; 620.5
• DOI: 10.1002/smll.201701677
• Languages: English
• ISSNs: 1613-6810

Abstract

Abstract : 2D metal chalcogenide (MC) nanosheets (NS) have displayed high capacities as lithium‐ion battery (LiB) anodes. Nevertheless, their complicated synthesis routes coupled with low electronic conductivity greatly limit them as promising LiB electrode material. Here, this work reports a facile single‐walled carbon nanotube (SWCNT) percolating strategy for efficiently maximizing the electrochemical performances of gallium chalcogenide (GaX, X = S or Se). Multiscaled flexible GaX NS/SWCNT heterostructures with abundant voids for Li + diffusion are fabricated by embedding the liquid‐exfoliated GaX NS matrix within a SWCNT‐percolated network; the latter improves the electron transport and ion diffusion kinetics as well as maintains the mechanical flexibility. Consequently, high capacities (i.e., 838 mAh g −1 per gallium (II) sulfide (GaS) NS/SWCNT mass and 1107 mAh g −1 per GaS mass; the latter is close to the theoretical value) and good rate capabilities are achieved, which can be majorly attributed to the alloying processes of disordered Ga formed after the first irreversible GaX conversion reaction, as monitored by in situ X‐ray diffraction. The presented approach, colloidal solution processing of SWCNT and liquid‐exfoliated MC NS to produce flexible paper‐based electrode, could be generalized for wearable energy storage devices with promising performances. Abstract : A facile single‐walled carbon nanotube (SWCNT) percolating strategy for efficiently maximizing the electrochemical performances of liquid‐phase exfoliated gallium chalcogenide nanosheets (NS; GaX, X = S or Se) is reported. The unique heterostructure enables high capacities in GaS NS/SWCNT composites, reaching the theoretical capacity of the GaS component (1107 mAh g −1 at 100 mA g −1 ).