Introducing Bioinspired Initiator into Resins for In Situ Repairing of 3D-Printed Metallic Structures.

Delicate metal parts with superior electrical, mechanical, and thermal properties have attracted a lot of interest, but it is yet challenging to fabricate. Herein, a strategy of making complex metallic structures is developed in this research through integrating a bioinspired catechol-based initiator, dopamine, as an example, into the three-dimensional (3D) printing process followed by the assistance of surface modification. The wealthy catechol groups growing on the polymer enable the metal coating with a high adhesion stability. A series of complex metallic structures were fabricated, such as Ni-Co, Cu, and Ni Eiffel towers, Ag micro-stretching-dominated architecture, and Au auxetic structure. The introduced metal coating enables the 3D-printed objects with multiple classes of functionalities, such as magnetism or high conductivity. In particular, this method allows in situ repairing of the damaged metallic structures, which not only prolongs the lifespan of products but also solves the long-lasting challenge of repairing 3D printing parts. The detailed fabrication and repairing processes of functional metallic parts are presented and discussed. The proposed strategy has great potential in practical applications related to electronics, energy storage, healthcare, and so on.