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Abstract Lithium‐ion and sodium‐ion batteries (LIBs and SIBs) are crucial in our shift toward sustainable technologies. In this work, the potential of layered boride materials (MoAlB and Mo2AlB2) as novel, high‐performance electrode materials for LIBs and SIBs, is explored. It is discovered that Mo2AlB2shows a higher specific capacity than MoAlB when used as an electrode material for LIBs, with a specific capacity of 593 mAh g−1achieved after 500 cycles at 200 mA g−1. It is also found that surface redox reactions are responsible for Li storage in Mo2AlB2, instead of intercalation or conversion. Moreover, the sodium hydroxide treatment of MoAlB leads to a porous morphology and higher specific capacities exceeding that of pristine MoAlB. When tested in SIBs, Mo2AlB2exhibits a specific capacity of 150 mAh g−1at 20 mA g−1. These findings suggest that layered borides have potential as electrode materials for both LIBs and SIBs, and highlight the importance of surface redox reactions in Li storage mechanisms.
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Unlocking High Capacity and Fast Na + Diffusion of H x CrS 2 by Proton‐Exchange Pretreatment
Abstract This study presents a new material, “HxCrS2” (denotes approximate composition) formed by proton‐exchange of NaCrS2which has a measured capacity of 728 mAh g−1with significant improvements to capacity retention, sustaining over 700 mAh g−1during cycling experiments. This is the highest reported capacity for a transition metal sulfide electrode and outperforms the most promising proposed sodium anodes to date. HxCrS2exhibits a biphasic structure featuring alternating crystalline and amorphous lamella on the scale of a few nanometers. This unique structural motif enables reversible access to Cr redox in the material resulting in higher capacities than seen in the parent structure which features only S redox. Pretreatment by proton‐exchange offers a route to materials such as HxCrS2which provide fast diffusion and high capacities for sodium‐ion batteries.
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- Award ID(s):
- 2011750
- PAR ID:
- 10391426
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 35
- Issue:
- 10
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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