通过触发α → β相位过渡来增强化阳极,以获得优质的离子储存
Shaokun Chong1, Ting Li1, Shuangyan Qiao1
1Frontiers Science Center for Flexible Electronics, Institute of Flexible Electronics, Northwestern Polytechnical University, Xi'an 710072, China.
ACS nano
|January 18, 2024
概括
离子电池 (SIB) 的新阳极材料至关重要. 这项研究引入了α-MnSe纳米棒作为高性能阳极,证明了SIBs的卓越稳定性和能量密度.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 储能 储能 储能 储能 储能 储能
背景情况:
- 石墨和阳极不适合用于离子电池 (SIB).
- 开发高性能阳极材料对于SIB的发展至关重要.
- 丰富且低成本的资源推动了SIB的研究.
研究的目的:
- 为了合成和评估α-MnSe纳米棒来源于δ-MnO2作为SIBs的阳极.
- 研究离子插入/提取过程中α-MnSe的电化学机制和结构演变.
- 证明 δ-α-MnSe 作为高性能 SIB 的可行阳极材料的潜力.
主要方法:
- 从δ-MnO2.2.中合成α-MnSe纳米棒.
- 电化学表征包括循环电压测量和静电循环.
- 第一个原则计算来研究N-ion迁移和相位过渡.
- 制造和测试充满电池的离子电池.
主要成果:
- 在初始循环后α-MnSe转化为β-MnSe,表现出转化机制.
- 第一原理计算证实,离子迁移驱动了α → β相位过渡.
- 由此产生的β-MnSe结构具有较低的Na-离子扩散屏障,可提供增强的稳定性和动力学.
- δ-α-MnSe阳极表现出极好的速率能力和周期稳定性 (>1000个周期),衰变速率低 (0.0267%/周期).
- 离子充电电池实现了281.2Wh·kg-1的高能量密度和出色的循环使用性.
结论:
- δ-α-MnSe纳米棒是离子电池的有效阳极.
- 阶段过渡到β-MnSe增强了结构完整性和电化学性能.
- 由于其稳定性和能量密度,这种材料在实际SIB应用中具有显著的潜力.
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