1成果简介 

        柔性铝离子电池因其高安全性、低成本、铝资源丰富以及优异的机械柔韧性，在可穿戴电子设备领域展现出巨大的应用潜力。然而，该领域面临一个关键瓶颈：如何快速、低成本地制备同时具备高导电性、结构稳定性和优异电化学活性的柔性正极材料。化学气相沉积（CVD）制备的碳纳米管（CNT）薄膜是理想的柔性正极候选材料，但CVD过程残留的铁（Fe）催化剂杂质严重降低了材料的纯度和电化学性能，而传统的酸洗纯化工艺耗时长、破坏CNT结构，且难以同步修复碳缺陷。

        本文，天津师范大学Yue Wu、Dejun Li等在Journal of Materials Chemistry A期刊发表名为"Flash Joule Heating Enabled Instantaneous Purification and Strengthening of CNT Films for High-Performance Flexible Aluminum-Ion Batteries"的论文。该研究创新性地引入闪蒸焦耳加热（Flash Joule Heating, FJH）技术，对CVD制备的CNT薄膜进行瞬时高温处理（最高达1700°C），在极短时间内同时实现了：

        高效纯化——通过瞬时高温蒸发去除CNT薄膜中残留的Fe催化剂杂质

        结构强化——通过缺陷修复和石墨化程度显著提升，增强CNT的结构完整性和导电性

        优化后的闪蒸CNT正极（1700°C处理）在4 A g?1电流密度下实现了281.97 mAh g?1的高比容量，是原始CNT薄膜的7.57倍。不同温度（1000–1700°C）处理的CNT薄膜均展现出显著的性能提升，证明了闪蒸焦耳加热技术作为一种快速、高效、极具前景的高性能柔性储能电极制备新路径。

        2图文导读  

        

        图1、 The preparation process of materials. (a) Preparation of carbon nanotube films by chemical vapor deposition; (b) Joule heat roll to roll fast heating; (c) installation of aluminum-ion batteries.

        

        图2、 (a) SEM image of the CNTF; (b) SEM high resolution image of the CNTF; (c) STEM dark field image of the CNTF and TEM elemental mapping of C, Fe and O; (d) SEM image of CNTF-1000; (e) SEM high resolution image of CNTF-1000; (f) STEM dark field image of CNTF-1000 and TEM elemental mapping of C, Fe and O; (g) SEM image of CNTF-1200; (h) SEM high resolution image of CNTF-1200; (i) STEM dark field image of CNTF-1200 and TEM elemental mapping of C, Fe and O; (j) SEM image of CNTF-1400; (k) SEM high resolution image of CNTF-1400; (l) STEM dark field image of CNTF-1400 and TEM elemental mapping of C, Fe and O; (m) SEM image of CNTF-1700; (n) SEM high resolution image of CNTF-1700; (o) STEM dark field image of CNTF-1700 and TEM elemental mapping of C, Fe and O.

        

        图3、(a and b) TEM images of the CNTF at different magnifications; (c) HRTEM image of the interplanar distance of the CNTF; (d) SAED image of the CNTF; (e and f) TEM images of CNTF-1000 at different magnifications; (g) HRTEM image of the interplanar distance of CNTF-1000; (h) SAED image of CNTF-1000; (i and j) TEM images of CNTF-1200 at different magnifications; (k) HRTEM image of the interplanar distance of CNTF-1200; (l) SAED image of CNTF-1200; (m and n) TEM images of CNTF-1400 at different magnifications; (o) HRTEM image of the interplanar distance of CNTF-1400; (p) SAED image of CNTF-1400; (q and r) TEM images of CNTF-1700 at different magnifications; (s) HRTEM image of the interplanar distance of CNTF-1700; (t) SAED image of CNTF-1700.

        

        图4、(a) XPS signatures of CNTF, CNTF-1000, CNTF-1200, CNTF-1400 and CNTF-1700 samples; the XPS profiles of the (b) C 1s signal, (c) O 1s signal and (d) Fe 2p signal; (e) XRD pattern; (f) Raman spectra.

        

        图5、(a–e) CV curves for CNTF, CNTF-1000, CNTF-1200, CNTF-1400 and CNTF-1700 samples; (f–j) b-values at each redox potential; (k–o) comparison of the percentage contributions of capacitive and diffusion-controlled processes for the five samples.

        

        图6、Electrochemical performance of the CNTF, CNTF-1000, CNTF-1200, CNTF-1400 and CNTF-1700 cathodes. (a) Rate performance for each current density; (b–f) the corresponding charge–discharge voltage profiles of a; (g) cycling stability at 4 A g?1 current rate; (h–l) charge–discharge voltage curves for g; (m) long-term cycling stability of the CNTF-1700 cathode for 10?000 cycles; (n) Nyquist plots of the five samples.

        

        图7、(a) Mechanism of multi-ion intercalation into the carbon nanotube film cathode; (b) TEM image of the cycled electrode in a fully charged state after 1000 cycles; (c) TEM image and EDS mapping of the CNTF-1700 electrode, showing the distribution of C, Al, Cl and Si elements in the fully charged state; (d) TEM image of the cycled electrode in the fully discharged state after 1000 cycles; (e) TEM image and EDS mapping of the CNTF-1700 electrode, showing the distribution of C, Al, Cl and Si elements in the fully discharged state; Ex situ XPS data of the (f) C 1s, (g) Cl 2p and (h) Al 2p peaks for pristine, fully charged and fully discharged CNTF-1700.

        3小结 

        总而言之，该工作创新性地将闪蒸焦耳加热（FJH）技术应用于CVD制备的CNT薄膜的后处理，在极短时间内同步实现了Fe催化剂杂质的高效去除（纯化）和碳缺陷修复与石墨化度显著提升（强化）两大目标。优化后的闪蒸CNT正极（1700°C处理）在柔性铝离子电池中实现了281.97 mAh g?1（4 A g?1）的高比容量，较原始CNT薄膜提升了7.57倍。更重要的是，该FJH技术具有处理时间极短（秒级）、无需酸洗试剂、节能高效、易于规模化等突出优势，为高性能柔性储能电极的快速制备提供了一条全新路径。该工作不仅推动了柔性铝离子电池正极材料的发展，也为闪蒸焦耳加热技术在碳基纳米材料纯化与结构调控中的广泛应用提供了重要的实验依据和方法参考。

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