石墨烯-碳纳米管/PAM/CCS三重网络水凝胶，EMI屏蔽和柔性电子产品

摘要：通过引入低密度刚性填充网络来改进传统的多网络水凝胶，从而优化单一离子导电性，并克服有限的电磁特性以生产电磁干扰（EMI）屏蔽水凝胶，这是一项开创性的挑战。本文，东华大学Yonggen Lu、吴琪琳教授团队在《ADVANCED FUNCTIONAL MATER

1成果简介

通过引入低密度刚性填充网络来改进传统的多网络水凝胶，从而优化单一离子导电性，并克服有限的电磁特性以生产电磁干扰（EMI）屏蔽水凝胶，这是一项开创性的挑战。本文，东华大学Yonggen Lu、吴琪琳教授团队在《ADVANCED FUNCTIONAL MATERIALS》期刊发表名为“SGs-CNTs/PAM/CCS Triple Network Hydrogel: Neural Architecture Inspired for Broadband EMI Shielding and Environmental Resilience”的论文，研究从神经网络中汲取灵感，推出了一种新型三重网络（TN）水凝胶。

单层石墨烯（SGs）和碳纳米管（CNTs）分别模拟了类似神经元和轴突/树突的导电通道，并通过羧甲基壳聚糖（CCS）和聚丙烯酰胺（PAM）辅助填料的分散-搭接-固定过程。SGs-CNTs 的这种协同装配加上水分子的存在，使 SGs-CNTs/CCS/PAM (SCCP) 水凝胶在 8.2-26.5 GHz 范围（X、Ku 和 K 波段）内具有优异的电磁干扰屏蔽效果（SE），SE 分别达到 42.31、50.20 和 60.78 dB。此外，SGs-CNTs 的光热特性使CCS/PAM能够在暴露于近红外（NIR）光时有效愈合断面并恢复电磁特性。通过氯化锂的水合作用，SCCP 还能将凝固点显著降至 -43 °C。SCCP具有多样化的制造工艺、自愈特性和优异的环境耐久性，是电磁干扰屏蔽的理想候选材料，在柔性电子产品的多功能应用方面具有卓越的潜力。

2图文导读

图1、a) The microstructure formation process of SGs-CNTs/CCS/PAM (SCCPt) hydrogels. b) Glossy surface and extensibility of SCCP10. c,d) Manufacture of conductive pathways by writing.

图2、a,b) Effect of filler content and ratio of SGs and CNTs on the conductivity of hydrogels. c) Description of conductive networks based on modified classical percolation theory. d) Size of agglomerates in different solutions. e) Comparison of UV absorbance at the top and bottom of different solutions. f,g) Dispersion stability of different solutions. h) Zeta potential of different solutions. i) TEM image of nerve-like networks. j) Contact nodes of a nerve-like network. k) Schematic diagram of neural network. l) SEM images of nerve-like conductive networks.

图3、a) Stress–strain curve of SCCPt hydrogels. b) Mechanical property parameters of SCCPt. c) Cyclic tensile curve of SCCP10. d,e) Mechanical flexibility and microscopic interpretation of SCCP10. f) Puncture and cut resistance of SCCP10. g) Schematic diagram of microstructure under tensile behavior. h) Porous structure of SCCP10. i,j) Compression resilience behavior and microscopic interpretation of SCCP10 at 80% compression ratio.

图4、a,b) EMI SE of SCCPt hydrogels at different t-values. c) EMI SE of different thicknesses of SCCP10. d) Power coefficients of SCCP hydrogels at different values of t. e) EMI shielding mechanism of SCCP10. f) The performance of SCCP10 has a low filler ratio compared to other work. g–j) Visualization of SCCP10 in CST simulation, Power Loss density, E-field, H-Field, and Power Flow.

图5、a) The self-healing properties of SCCP10 in 10 min. b–d) NIR-promoted healing behavior of SCCP10. e,f) NIR photothermal warming effect of SCCP10. g) Repair mechanism of SCCP10 based on NIR photothermal warming effect. h,i) Rapid repair of electrical properties of SCCP10. j) Repair of EMI SE of SCCP10. k) Repair of the mechanical properties of SCCP10.

图6、a,b) DSC curves and water content analysis of SCCP10 with different LiCl contents. c,d) Raman spectroscopy of SCCP10 with different LiCl contents and I3207/I3443. e,f) Analysis of T2 relaxation time and hydrographic properties of SCCP10 with different LiCl contents. g,h) Freezing behavior of SCCP10 with different LiCl contents. i) Water loss and retention of SCCP10 with 5% LiCl at different humidity levels.

图7、a) Dual mode cyclic strain before and after EMI SE. b–d) 30-min UV exposure test and changes of EMI SE. e,f) Solvent resistance test and corresponding EMI SE retention. g,h) Effect of bimodal cyclic healing behavior on EMI SE.

图8、a,b) Manufacturing of mould using expanded dimensions. c,d) Manufacturing using a shaped mould. e) Manufactured by spraying. f) Fracture repair of EMI shielding masks using precursor solutions. g) Filling of potholes that are not self-healing using precursor solutions. h) Adhesion of SCCP10. i) SCCP10 wrapped around a mannequin. j,k) Interference effect of SCCP10 on GPS tracker signals. l–o) Non-flammable and protective properties of SCCP10 at high burning temperatures. p–s) Attach the SCCP10 to the CPU location on the phone's back panel to assist with heat dissipation.

3小结

在填料浓度小于 1.2 wt.% 的情况下，构建了具有神经网络状结构的 SCCP TN 水凝胶。碳网络、CCS/PAM 的聚合物多孔结构以及水的极化效应使 SCCP 在 8.2 至 26.5 GHz 的宽频率范围内表现出实用的 EMI 屏蔽效果。在 X 波段、Ku 波段和 K 波段，SCCP（4.5毫米）的 EMI SE 均大于 40 分贝，并可根据厚度变化进行调整。此外，通过利用 SGs-CNT 的光热效应，SCCP 在 808 纳米的近红外波段显示出更强的愈合能力和关键性能的恢复能力。SCCP 的凝固点为 -43 °C，并能通过氯化锂的水合作用耐受低湿度，其多功能制造和多功能性可广泛应用于可穿戴电子设备、智能电子织物和其他需要柔性 EMI 屏蔽材料的领域，尤其是在具有挑战性的温度和湿度条件下。

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