Additive manufacturing lets us design materials from the microstructure up. With collaborators in chemistry, we 3D print dual-scale gyroid structures whose nanoporous walls carry custom molecular receptors. These form modular cartridges that selectively capture critical elements from mixed streams. We also develop graphene–copper composite conductors that pair copper’s conductivity with improved thermal stability for aerospace power applications, and we study laser powder bed fusion of pure copper. Using vat photopolymerization with in-situ phase separation, we print highly porous polymer structures whose pore architecture can be tuned to control how drugs are released from implants.