Yan Qian, Liu Zonglin, Xiong Jinhua, Lian Huanxin, Chen He, Fei Teng, Chen Yunxiang, Zheng Haowen, Zhao Xu, Xu Liangliang, Xue Fuhua, Zhong Yesheng, Ma Xiaoliang, Shi Liping, Peng Qingyu, He Xiaodong
National Key Laboratory of Science and Technology on Advanced Composites in Special Environments, Center for Composite Materials and Structures, Harbin Institute of Technology, Harbin, 150080, P. R. China.
Suzhou Research Institute of HIT, Suzhou, 215104, China.
Adv Sci (Weinh). 2025 Aug;12(31):e05551. doi: 10.1002/advs.202505551. Epub 2025 May 30.
Smart electromagnetic interference (EMI) shielding materials capable of reversible EMI response hold great promise for application in flexible electromagnetic devices. Here, PPM hydrogels composed of poly (N-isopropylacrylamide) (PNIPAM) and MXene/PEDOT: PSS hybrid fillers are fabricated via ice-templated freeze-in-situ polymerization. The anisotropic structural design of the hydrogel enhances its mechanical properties, conductivity, and EMI shielding properties in a specific direction. Furthermore, it can rapidly adjust its internal water content under thermal and light stimulation. The EMI shielding performance of PPM hydrogels can transition from an EMI shielding status (EMI shielding on, >50 dB) to an EM-wave-transparent status (EMI shielding off, ≈2 dB) in the X-band with the dynamic change in water content. Notably, the EMI SE value of PPM hydrogel in the X-band can be quantitatively adjusted from ≈59.3 to 15.5 dB, demonstrating excellent repeatability and adjustability. A real-time electrical switching capability in the broad GHz frequency range (8.2-40 GHz) is achieved through dual stimuli-responsive (temperature-responsive and light-responsive) modulation. This study presents a new model for dynamically switchable EMI shielding and reveals the great application potential of smart on/off switchable hydrogel-based EMI shielding materials as next-generation multifunctional electronics.
具有可逆电磁干扰（EMI）响应的智能电磁干扰屏蔽材料在柔性电磁设备中具有广阔的应用前景。在此，通过冰模板原位冷冻聚合制备了由聚（N-异丙基丙烯酰胺）（PNIPAM）和MXene/PEDOT:PSS混合填料组成的PPM水凝胶。水凝胶的各向异性结构设计在特定方向上增强了其机械性能、导电性和电磁干扰屏蔽性能。此外，它可以在热和光刺激下快速调节其内部含水量。随着含水量的动态变化，PPM水凝胶的电磁干扰屏蔽性能在X波段可以从电磁干扰屏蔽状态（电磁干扰屏蔽开启，>50 dB）转变为电磁波透明状态（电磁干扰屏蔽关闭，≈2 dB）。值得注意的是，PPM水凝胶在X波段的电磁干扰屏蔽效能（EMI SE）值可以从≈59.3定量调节到15.5 dB，显示出优异的可重复性和可调节性。通过双刺激响应（温度响应和光响应）调制，在宽GHz频率范围（8.2 - 40 GHz）实现了实时电开关能力。本研究提出了一种动态可切换电磁干扰屏蔽的新模型，并揭示了基于智能开/关可切换水凝胶的电磁干扰屏蔽材料作为下一代多功能电子产品的巨大应用潜力。
