Hubei Engineering Research Center of Radio Frequency Microwave Technology and Application, Wuhan University of Technology, Wuhan, 430070, P. R. China.
State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan, 430070, P. R. China.
Adv Mater. 2022 Dec;34(50):e2206101. doi: 10.1002/adma.202206101. Epub 2022 Nov 7.
Assembling pristine graphene into freestanding films featuring high electrical conductivity, superior flexibility, and robust mechanical strength aims at meeting the all-around high criteria of new-generation electronics. However, voids and defects produced in the macroscopic assembly process of graphene nanosheets severely degrade the performance of graphene films, and mechanical brittleness often limits their applications in wide scenarios. To address such challenges, an electrostatic-repulsion aligning strategy is demonstrated to produce highly conductive, ultraflexible, and multifunctional graphene films. Typically, the high electronegativity of titania nanosheets (TiNS) induces the aligning of negatively charged graphene nanosheets via electrostatic repulsion in the film assembly. The resultant graphene films show fine microstructure, enhanced mechanical properties, and improved electrical conductivity up to 1.285 × 10 S m . Moreover, the graphene films can withstand 5000 repeated folding without structural damage and electrical resistance fluctuation. These comprehensive improved properties, combined with the facile synthesis method and scalable production, make these graphene films a promising platform for electromagnetic interference (EMI) shielding and thermal-management applications in smart and wearable electronics.
将原始石墨烯组装成具有高导电性、卓越柔韧性和强韧机械强度的独立膜，旨在满足新一代电子设备的全方位高标准要求。然而，在石墨烯纳米片的宏观组装过程中产生的空隙和缺陷严重降低了石墨烯膜的性能，而机械脆性通常限制了它们在广泛场景中的应用。为了解决这些挑战，展示了一种静电排斥对齐策略，以生产出高导电、超柔韧和多功能的石墨烯膜。通常情况下，二氧化钛纳米片（TiNS）的高电负性通过在膜组装过程中的静电排斥诱导带负电荷的石墨烯纳米片的对齐。所得的石墨烯膜显示出精细的微观结构、增强的机械性能和高达 1.285×10 S m 的电导率提高。此外，石墨烯膜可以承受 5000 次重复折叠而不会出现结构损坏和电阻波动。这些综合性能的改善，结合简便的合成方法和可扩展的生产，使这些石墨烯膜成为智能和可穿戴电子设备中电磁干扰（EMI）屏蔽和热管理应用的有前途的平台。
