Gallium Sulfide–Single‐Walled Carbon Nanotube Composites: High‐Performance Anodes for Lithium‐Ion Batteries. (8th July 2014)

• Record Type: Journal Article
• Authors: Meng, Xiangbo; He, Kai; Su, Dong; Zhang, Xiaofeng; Sun, Chengjun; Ren, Yang; Wang, Hsien‐Hau; Weng, Wei; Trahey, Lynn; Canlas, Christian P.; Elam, Jeffrey W.
• Is Part Of: Advanced functional materials. Volume 24:Number 34(2014)
• Page Start: 5435
• Page End: 5442
• Publication Date: 2014-07-08
• Subjects: Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adfm.201401002
• Languages: English
• ISSNs: 1616-301X

Abstract

<abstract abstract-type="main" xml:lang="en"> <title> <x xml:space="preserve">Abstract</x> </title> <p>Metal sulfides are an important class of functional materials possessing exceptional electrochemical performance and thus hold great promise for rechargeable secondary batteries. In this work, we deposited gallium sulfide (GaS<sub>x</sub>, x = 1.2) thin films by atomic layer deposition (ALD) onto single‐walled carbon nanotube (SWCNT) powders. The ALD GaS<sub>x</sub> was performed at 150 °C, and produced uniform and conformal amorphous films. The resulting core‐shell, nanostructured SWCNT‐GaS<sub>x</sub> composite exhibited excellent electrochemical performance as an anode material for lithium‐ion batteries (LIBs), yielding a stable capacity of ≈575 mA g<sup>–1</sup> at a current density of 120 mA g<sup>–1</sup> in the voltage window of 0.01–2 V, and an exceptional columbic efficiency of >99.7%. The GaS<sub>x</sub> component of the composite produced a specific capacity of 766 mA g<sup>–1</sup>, a value two times that of conventional graphite anodes. We attribute the excellent electrochemical performance of the composite to four synergistic effects: 1) the uniform and conformal ALD GaS<sub>x</sub> coating offers short electronic and Li‐ion pathways during cycling; 2) the amorphous structure of the ALD GaS<sub>x</sub> accommodates stress during lithiation‐delithiation processes; 3) the mechanically robust SWCNT framework also accommodates stress from cycling; 4) the SWCNT matrix provides a continuous, high conductivity network.</p> </abstract>