University of Delaware,
Keywords: 3D printing, 0D/1D/2D materials, complex architectures
Summary:Carbon nanomaterials, including 0D carbon nanopowders, 1D carbon nanotubes, and 2D graphene, exhibit scaling effect and exceptional properties with great interest in structural and functional applications. The integration of carbon nanomaterials and architectural features at multiple length scales into structural mechanics and functional materials has significantly shifted the paradigm of materials engineering toward materials by design with structural and functional capabilities. Three-dimensional carbon multiscale architectures featuring the characteristics of both the constituent CNT material, which brings the effects of its feature nanoscale resolution and properties, as well as the structures across multiscale lengths offer breakthrough advances in many applications including ultra-light structural materials, energy storage, and biomedical devices. However, there is no effect approach to assemble those carbon nanomaterials into macro-scale structures with desired architecture while ensuring scaling properties. There are several fabrication challenges must be addressed, including complex 3D geometrics, multiscale structure, multimaterials in structure, and manufacturing throughput. Advanced and evolving AM techniques (e.g., light-based methods, and direct ink white method for fabrication of architected materials) could be applied to overcome many of these challenges, but these methods are still under development and not widely available for industrial scales and applications. Therefore, it is highly anticipated to develop new manufacturing technology to handle nanomaterials and assemble them into large-scale structure with complex architectural features in a fast and efficient way. In my talk, I will introduce our recent work on additive manufacturing of three-dimensional carbon-based multiscale architectures, and demonstrate its applications in electrochemical energy storage. Our method will retain the properties of carbon nanomaterials and there no additional binder or polymer in the final 3D components. We have demonstrated that carbon nanomaterials, including 0D carbon nanopowders, 1D carbon nanotubes, and 2D graphene, could be all processed into complex three-dimensional multiscale carbon architectures. Particularly, 3D carbon nanotubes structures show record-high compression stress compared to all reported carbon nanotubes sponges and structure. Beyond, carbon architectures, ceramics and metals architectures have been demonstrated by conformally coating ceramics (e.g., Al2O3 by atomic layer deposition) or metals (e.g., nickel by metal sputtering). These carbon nanomaterials serve as sacrificial template to anchor ceramic and metal deposition, and then could be pyrolyzed at high temperature in air. The ceramic and metal multiscale architectures could be retained with the same architectures of carbon structure. In addition, our additive manufacturing method could join components with different carbon materials and architectures together. Our method provides a scalable and cost-effective manufacturing way to fabricate complex multiscale architectures.