The electrochemical lithium-ion intercalation properties of molybdenum metal-cluster oxide LixMo4O6 (0.33 ≤ x ≤ 1.0) in an organic electrolyte of 1.0 M LiPF6 in ethylene carbonate/dimethyl carbonate (1:2 v/v) were characterized for the first time. Li0.66Mo4O6 (tetragonal, P4/mbm, a = 9.5914(3) Å, c = 2.8798(1) Å, V = 264.927(15) Å3, Z = 2) was prepared via ion-exchange of indium and lithium ions from InMo4O6 (tetragonal, P4/mbm, a = 9.66610(4) Å, c = 2.86507(2) Å, V = 267.694(2) Å3, Z = 2), which was first synthesized from a stoichiometric mixture of In, Mo, and MoO3 via a solid-state reaction for 11 h at 1100 °C. Then, Li0.33Mo4O6 was obtained via electrochemical charge of the electrode at 3.4 V vs. Li. The electrochemical lithium-ion insertion into Li0.33Mo4O6 occurs stepwise: three separate peaks were observed in the cyclic voltammogram and three quasi-plateaus in the galvanostatic profile, indicating a complicated intercalation mechanism. However, examination of the structural evolution of LixMo4O6 during the electrochemical cycle indicated a reversible reaction over the measured voltage range (2.0–3.2 V) and x range (0.33 ≤ x ≤ 1.00). Despite the excellent electrochemical reversibility, LixMo4O6 showed poor rate performance with a low capacity of 36.3 mAh g−1 at a rate of 0.05 C. Nonetheless, this work demonstrates a new structural class of lithium cathode materials with condensed metal clusters and 1D tunnels, and provides a host material candidate for multivalent-ion batteries.
|Number of pages||6|
|Journal||Journal of Solid State Chemistry|
|State||Published - Oct 2017|
Bibliographical noteFunding Information:
This research was supported by Creative Materials Discovery Program through the National Research Foundation of Korea (NRF) and funded by the Ministry of Science, ICT and Future Planning (2015M3D1A1069707).
© 2017 Elsevier Inc.
- Crystal structure
- Li intercalation
- Lithium ion battery
- Molybdenum metal cluster