Electrical Conductivity and Photodetection in 3D-Printed Nanoporous Structures via Solution-Processed Functional Materials

3D-printed conductive structures are highly attractive due to their great potential for customizable electronic devices. While the traditional 3D printing of metal requires high temperatures to sinter metal powders or polymer/metal composites, low or room temperature processes will be advantageous to enable multi-material deposition and integration of optoelectronic applications. Herein, digital light processing technology and inkjet printing are combined as an effective strategy to fabricate customized 3D conductive structures. In this approach, a 3D-printed nanoporous (NPo) polymeric material is used as a substrate onto which a nanoparticle-based Ag ink is printed. SEM and X-ray nano computed tomography (nanoCT) measurements show that the porous morphology of the pristine NPo is retained after deposition and annealing of the Ag ink. By optimizing the deposition conditions, conductive structures with sheet resistance <2 Ω sq-1 are achieved when annealing at temperatures as low as 100 °C. Finally, the integration of an inkjet-printed photodetector is investigated based on an organic semiconductor active layer onto the NPo substrate. Thus, the potential of this approach is demonstrated for the additive manufacturing of functional 3D-printed optoelectronic devices.