在磁性MXene基微波吸收器中由等级架构诱导的链接效应
Lei Cai1, Haojie Jiang1, Fei Pan1
1Shanghai Key Lab. of D&A for Metal-Functional Materials, School of Materials Science & Engineering, Tongji University, Shanghai, 201804, P. R. China.
Small (Weinheim an der Bergstrasse, Germany)
|October 16, 2023
概括
在MXene-气凝中的层次结构工程增强了微波吸收 (MA) 和多功能性. 状结构的气凝显示出卓越的MA性能和出色的机械,热和疏水性质.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 电磁学 电磁学 电磁学 电磁学
背景情况:
- 层次架构工程是整合材料属性的关键.
- 开发多功能微波吸收材料需要了解结构-属性关系.
- 目前对细胞单元机制的理解限制了最大限度地提高微波吸收和多功能性.
研究的目的:
- 为了研究层次结构和微波吸收性能之间的关系.
- 制造具有可变结构的MXene气凝,用于多功能应用.
- 阐明优越微波吸收和衍生多功能性的机制.
主要方法:
- 使用上下冰模板方法制造具有无序,多孔和片状结构的MXene气凝.
- 结构性,机械性,电磁性,热性和疏水性质的表征.
- 基于反射损失和有效吸收带宽的微波吸收性能评估.
主要成果:
- 板状结构的MXene-aerogel (0.015gcm−3密度) 显示了最佳的微波吸收 (最小反射损失:-53.87dB,有效吸收带宽:6.84GHz) 在6重%的填充比率下.
- 这种片状结构在微波吸收方面表现优于其他配置.
- 具有板状结构的MXene/CoNi复合气凝具有出色的机械性能 (经过1000个循环后>90%的压缩拉伸),弹性,疏水性和绝热性.
结论:
- 精确的微观结构设计对于实现卓越的微波吸收和多功能性至关重要.
- 层次结构显著影响MXene-aerogels的物理化学行为和宏观性质.
- 这项工作提出了一种新的战略,用于在单一材料中整合电磁隐形,隔热和承载能力.
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