Yan Jia, Zhou Tianzhu, Yang Xinyu, Zhang Zejun, Li Lei, Zou Zhaoyong, Fu Zhengyi, Cheng Qunfeng
School of Chemistry, Key Laboratory of Bio-inspired Smart Interfacial Science and Technology of Ministry of Education, Beihang University, Beijing, 100191, P. R. China.
School of Chemistry and Materials Science, University of Science and Technology of China, Hefei, 230026, P. R. China.
Angew Chem Int Ed Engl. 2024 Jul 22;63(30):e202405228. doi: 10.1002/anie.202405228. Epub 2024 Jun 19.
Nacre is a classic model, providing an inspiration for fabricating high-performance bulk nanocomposites with the two-dimensional platelets. However, the "brick" of nacre, aragonite platelet, is an ideal building block for making high-performance bulk nanocomposites. Herein, we demonstrated a strong and tough conductive nacre through reassembling aragonite platelets with bridged by MXene nanosheets and hydrogen bonding, not only providing high mechanical properties but also excellent electrical conductivity. The flexural strength and fracture toughness of the obtained conductive nacre reach ~282 MPa and ~6.3 MPa m, which is 1.6 and 1.6 times higher than that of natural nacre, respectively. These properties are attributed to densification and high orientation degree of the conductive nacre, which is effectively induced by the combined interactions of hydrogen bonding and MXene nanosheets bridging. The crack propagations in conductive nacre are effectively inhibited through crack deflection with hydrogen bonding, and MXene nanosheets bridging between aragonite platelets. In addition, our conductive nacre also provides a self-monitoring function for structural damage and offers exceptional electromagnetic interference shielding performance. Our strategy of reassembling the aragonite platelets exfoliated from waste nacre into high-performance artificial nacre, provides an avenue for fabricating high-performance bulk nanocomposites through the sustainable reutilization of shell resources.
珍珠层是一种经典模型，为制备具有二维片层的高性能块状纳米复合材料提供了灵感。然而，珍珠层的“砖块”——文石片层，是制备高性能块状纳米复合材料的理想构建单元。在此，我们通过用MXene纳米片桥接并通过氢键重新组装文石片层，展示了一种强韧的导电珍珠层，不仅具有高机械性能，还具有优异的导电性。所得导电珍珠层的弯曲强度和断裂韧性分别达到约282 MPa和约6.3 MPa m，分别比天然珍珠层高1.6倍和1.6倍。这些性能归因于导电珍珠层的致密化和高取向度，这是由氢键和MXene纳米片桥接的联合相互作用有效诱导的。通过氢键引起的裂纹偏转以及文石片层之间的MXene纳米片桥接，有效地抑制了导电珍珠层中的裂纹扩展。此外，我们的导电珍珠层还为结构损伤提供了自监测功能，并具有出色的电磁干扰屏蔽性能。我们将从废弃珍珠层中剥离的文石片层重新组装成高性能人造珍珠层的策略，为通过壳资源的可持续再利用制备高性能块状纳米复合材料提供了一条途径。
