北京石墨烯研究院刘忠范院士《Adv Sci》：蒙烯氧化铝纤维：可连续扩展的制备工艺及其在纤维增强聚合物复合材料中的电热应用

成果简介

蒙烯氧化铝纤维（GAF）是一种新型复合材料，通过化学气相沉积（CVD）技术使石墨烯在单根氧化铝纤维表面形成复合性生长层。该材料兼具石墨烯的高导电性和氧化铝纤维的强度特性，在电热应用及结构功能集成复合材料领域展现出广阔前景。本文，北京大学/北京石墨烯研究院刘忠范院士、Yue Qi等研究人员在《ADVANCED SCIENCE》期刊发表名为“Graphene-Skinned Alumina Fiber: Continuously Scalable Fabrication and Its Electrothermal Application in Fiber-Reinforced Polymer Composites”的论文，研究报道了采用自制卷对卷（RTR）CVD系统实现GAF的动态、连续、可扩展生产。该系统通过多级压力调节和氮气帘式吹扫技术，集脱胶与生长腔室于一体。制备的GAF具有优异柔韧性、高抗拉强度（>1.1 GPa）及可调导电率（40–1260 S m⁻¹）。

该系统确保批次内/批次间稳定性，年产能达5100–153 000米（具体取决于GAF规格）。GAF展现出卓越的电热性能：可调加热温度范围广（空气中约620°C，真空环境下>1200°C）、响应速度极快（>600°C s⁻¹）且循环稳定性高。此外，GAF与纤维增强聚合物（FRP）复合材料的制造工艺具有卓越兼容性。通过在不同取向的玻璃纤维/环氧树脂单向（UD）预浸料间夹层GAF，成功开发出GAF增强聚合物（GAFRP）复合材料，该材料展现出充分的树脂浸渍性和均匀的电热加热特性。这些发现凸显了GAF在结构功能集成FRP复合材料中的应用潜力，尤其适用于FRP广泛应用的领域，如飞机和风力涡轮机叶片的电加热防冰/除冰系统。

图文导读

图1、CVD growth of graphene on AF. (a) Schematic diagram of graphene CVD growth on AF using ethylene as the carbon precursor. (b) Photograph of GAF (∼50 m in length). (c) SEM image of GAF with well-maintained fiber profile (the fiber diameter is ∼9 µm). (d) Photograph of a GAF sample with a length of ∼2 m. (e) Raman spectra (normalized to G peak intensity) of GAF collected at points (A-J) in (d), spaced ∼22 cm apart along the central axis of the GAF. (f) Intensity mapping of the Raman 2D peak (∼2700 cm⁻¹) of a graphene ribbon obtained by etching the core AF of GAF. (g) Cross-sectional HR-TEM image of graphene on AF.

图2、Dynamic, continuous, and scalable production system of GAF. (a) Schematic diagram of GAF’s dynamic, continuous, and scalable production system, which primarily comprises a multi-axis unwinding module, pre-treatment chamber, multi-stage pressure regulation modules, growth chamber and a multi-axis rewinding module. (b–d) CFD simulations for the distribution of mole fraction of air (b), pressure distribution (c), and temperature distribution (d) in the growth chamber.

图3、Scalable preparation of GAF. (a) Raman peaks intensity ratios I_D/I_G and I_2D/I_G of GAF obtained at different C/H ratios (1:25, 1:30, 1:35, 1:40, 1:45, 1:50). (b) Graphene thickness and conductivity of GAF obtained with different C/H ratios. (c) Graphene thickness and conductivity of GAF obtained at different rewinding/unwinding rates (10–100 mm min⁻¹). (d) Photograph of GAF (with a length of ∼90 cm) from 5 batches (A–E), each under identical growth conditions. (e) Raman spectra collected at 10 evenly spaced positions, with uniform intervals of ∼10 cm over a lateral distance of ∼90 cm along the central axis of GAFs from the 5 batches in (d). (f) Raman intensity ratios I_D/I_G and I_2D/I_G derived from the Raman spectra in (e). (g) Conductivity collected between two adjacent sampling points, yielding 9 evenly spaced intervals, with uniform intervals of ∼10 cm over a lateral distance of ∼90 cm along the central axis of GAF from the 5 batches in (d).

图4、Mechanical and electrothermal performance of GAF. (a) Tensile strength and breaking elongation of pristine AF and GAF obtained at different growth temperatures (∼900°C, ∼1000°C, ∼1100°C for ∼2 h). The error bars represent the standard deviations (n = 5). (b) Resistance variation of GAF subjected to bending deformations at various bending radii (0.25–5 cm), with 100 bending times applied at each radius. The error bars represent the standard deviation (n = 5). (c) Resistance variation of GAF under various loading weights (0.05–2.05 N). The error bar represents the standard deviation (n = 5). (d) Infrared thermal image of GAF heating wire in both air and vacuum environments (air: 165.2 ± 5.1°C, 25 cm, ∼1040 S m⁻¹, ∼18 V voltage input; vacuum: 1158.8 ± 19.1°C, 10 cm, ∼1040 S m⁻¹, ∼52 V voltage input). (e) Temperature profiles of GAF heating wire under different input voltages in an air and a vacuum environment. (f) Heating rate and saturated temperature of GAF heating wire under different input voltages in an air environment. (g) Effect of graphene thickness of GAF heating wire on the heating rate and saturated temperature under different input voltages (∼15 V, ∼20 V, ∼50 V) in an air environment (the length of GAFs is all 10 cm, the conductivities of GAF are ∼43, ∼304, ∼907 and ∼1107 S m⁻¹, respectively). (h) Temperature response of GAF heating wire under square wave voltage cycles in a vacuum environment (0–33 V, a period of 12 s, 910 continuous cycles).

图5、Preparation and electrothermal performance of GAFRP composite. (a) Schematic illustration of the manufacturing process of the GAFRP composite, comprising four stages: lay-up of 10-layer glass fiber UD prepreg (orientation: 0°/+45°/90°/-45°/0), placement of GAF (each length of 12 cm, fiber laying density of ∼0.5 per cm², fiber spacing of 2 mm; each conductivity of ∼1260 S m⁻¹), vacuum degassing and thermal curing. (b) Photograph of the produced GAFRP composite. c) Cross-sectional SEM micrograph of the GAFRP composite. (d) Infrared thermal image of GAFRP heating plate (110 ± 0.7°C, ∼36.5 V voltage input). (e) Temperature profiles of the GAFRP heating plate under different input power densities. (f) Heating rate and saturated temperature of the GAFRP heating plate under different input power densities. (g) Temperature curve of GAFRP heating plate under a square wave from 0 to 33.6 V, with a period of 8 min and 306 cycles.

小结

在本研究中，作者开发了一套动态、连续且可扩展的GAF生产系统，以实现GAF的规模化生产。该系统采用自制RTR CVD设备，通过整合脱胶与CVD生长腔室的设计，结合多级压力调节及氮气帘式吹扫技术。通过对GAF规模化生产工艺的深入探索，成功优化了AF上生长石墨烯的质量。GAF展现出可调的石墨烯厚度与导电性，同时具备批次内/批次间稳定性，为持续稳定生产奠定坚实基础。制备的GAF兼具卓越的力学性能（高抗拉强度、优异抗弯曲性及强抗压性）与优异的电热性能。该材料在空气与真空环境下均展现出均匀的温度分布、良好的柔韧性、宽广的可调加热温度范围及超快响应特性。此外，GAF与FRP复合材料制造工艺具有高度兼容性。通过将GAF与玻璃纤维单向预浸料结合，制备出GAFRP复合材料，其具备良好的树脂浸渍能力与优异的电热性能。GAF将成为先进FRP复合材料中多功能应用的理想候选材料。

文献：https://doi.org/10.1002/advs.202524262