Additive manufacturing of metastructures at the micro- and nano-scale

, aiming to provide a comprehensive overview of current achievements and explore future potential. An array of additive manufacturing techniques are discussed, such as electrohydrodynamic printing, two-photon lithography, and aerosol jet printing, which are reshaping the fabrication of metastructures with unprecedented structural design and functional diversity. Furthermore, the selection of the materials based on fabrication principles and device functions is considered. The diverse applications based on different metastructures are highlighted. Finally, this review is concluded by discussing the current challenges and giving future perspectives.