Unconventional Pore and Defect Generation in Molybdenum Disulfide: Application in High-Rate Lithium-Ion Batteries and the Hydrogen Evolution Reaction
| Autor: | Wanjung Kim, Gee Woo Chang, Min-Sang Song, Xinjian Shi, Hwan Jin Kim, Jong Hyeok Park, Ki Jeong Kong, Kan Zhang, Ming Ma, Jeong Taik Lee, Jae Man Choi |
|---|---|
| Rok vydání: | 2014 |
| Předmět: |
Models
Molecular Materials science General Chemical Engineering Inorganic chemistry Molecular Conformation Oxide chemistry.chemical_element Overpotential law.invention chemistry.chemical_compound Electric Power Supplies law Electrochemistry Environmental Chemistry General Materials Science Disulfides Molybdenum disulfide Nanosheet Molybdenum Tafel equation Graphene General Energy Nanomesh chemistry Porosity Cobalt Hydrogen |
| Zdroj: | ChemSusChem. 7:2489-2495 |
| ISSN: | 1864-5631 |
| Popis: | A 2H-MoS2 (H=hexagonal) ultrathin nanomesh with high defect generation and large porosity is demonstrated to improving electrochemical performance, including in lithium-ion batteries (LIBs) and the hydrogen evolution reaction (HER), with the aid of a 3D reduced graphene oxide (RGO) scaffold as fast electron and ion channels. The 3D defect-rich MoS2 nanomesh/RGO foam (Dr-MoS2 Nm/RGO) can be easily obtained through a one-pot cobalt acetate/graphene oxide (GO) co-assisted hydrothermal reaction, in which GO, cobalt and acetate ions are co-morphology-controlling agents and defect inducers. As an anode material for LIBs, Dr-MoS2 Nm/RGO has only a 9% capacity decay at a 10 C discharge rate versus 0.2 C with stable cyclability at the optimized composition (5 wt% RGO to MoS2 and 2 mol% Co to Mo), and significantly achieves 810 mA h g(-1) at a high current density of 9.46 A g(-1) over at least 150 cycles. Moreover, Dr-MoS2 Nm/RGO exhibits superior activity for the HER with an overpotential as low as 80 mV and a Tafel slope of about 36 mV per decade. In contrast to the MoS2 nanosheet/RGO (MoS2 Ns/RGO), which is synthesized in the absence of cobalt ions, Dr-MoS2 Nm/RGO provides high interconnectivity for efficient lithium-ion transport, and rich defects as electrochemically active sites. DFT is used to prove the existence of rich defects due to anion replacement to become a Co-Mo-S atomic structure, releasing inert basal planes to active sites. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text