Gallium Sulfide–Single‐Walled Carbon Nanotube Composites: High‐Performance Anodes for Lithium‐Ion Batteries |
| |
Authors: | Xiangbo Meng Kai He Dong Su Xiaofeng Zhang Chengjun Sun Yang Ren Hsien‐Hau Wang Wei Weng Lynn Trahey Christian P. Canlas Jeffrey W. Elam |
| |
Affiliation: | 1. Energy Systems Division, Argonne National Laboratory, Argonne, IL, USA;2. Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY, USA;3. Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, IL, USA;4. Advanced Photon Source, Argonne National Laboratory, Argonne, IL, USA;5. Materials Science Division, Argonne National Laboratory, Argonne, IL, USA |
| |
Abstract: | 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 (GaSx, x = 1.2) thin films by atomic layer deposition (ALD) onto single‐walled carbon nanotube (SWCNT) powders. The ALD GaSx was performed at 150 °C, and produced uniform and conformal amorphous films. The resulting core‐shell, nanostructured SWCNT‐GaSx composite exhibited excellent electrochemical performance as an anode material for lithium‐ion batteries (LIBs), yielding a stable capacity of ≈575 mA g–1 at a current density of 120 mA g–1 in the voltage window of 0.01–2 V, and an exceptional columbic efficiency of >99.7%. The GaSx component of the composite produced a specific capacity of 766 mA g–1, 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 GaSx coating offers short electronic and Li‐ion pathways during cycling; 2) the amorphous structure of the ALD GaSx 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. |
| |
Keywords: | atomic layer deposition lithium‐ion battery gallium sulfide anode carbon nanotube composite high performance |
|
|