Abstract
Sodium-ion batteries are considered the most promising power source for electrical energy storage systems because of the abundance of sodium and their significant cost advantages. However, high-performance electrode materials are required for their successful application. Herein, we report a monoclinic-type CoMoO 4 material which is synthesized by a simple solution method. An optimized calcination temperature with a high crystallinity and a rodlike morphology of the material are selected after analyzing the as-synthesized powder by temperature-dependent time-resolved X-ray diffraction. The CoMoO 4 rods exhibit initial discharge and charge capacities of 537 and 410 mA h g -1 , respectively, when used as an anode for sodium-ion batteries. The sodium diffusion coefficient in the bimetallic CoMoO 4 anode is measured using the galvanostatic intermittent titration technique and calculated in the range of 1.565 × 10 -15 to 4.447 × 10 -18 cm 2 s -1 during the initial cycle. Further, the reaction mechanism is investigated using ex situ X-ray diffraction and X-ray absorption spectroscopy, and the obtained results suggest an amorphous-like structure and reduction/oxidation of Co and Mo during the sodium insertion/extraction process. Ex situ transmission electron microscopy and energy-dispersive spectroscopy images of the CoMoO 4 anode in fully discharged and recharged state reveal the rodlike morphology with homogenous element distribution.
Original language | English |
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Pages (from-to) | 3843-3851 |
Number of pages | 9 |
Journal | ACS Applied Materials and Interfaces |
Volume | 11 |
Issue number | 4 |
DOIs | |
State | Published - 30 Jan 2019 |
Keywords
- ex situ XRD
- monoclinic-type
- rodlike morphology
- temperature-dependent
- X-ray absorption spectroscopy