According to a team of U.S. government researchers in this study, nano3Dprint’s A2200 is “A platform for all 3D-printed electronics for the future.”* These 2020 research findings state that, “The demonstrated 3D-printed UV sensor can be a foundation for wearable and flexible electronics.”* With the wearable market valued at around $20B and the flexible electronics market valued at approximately $30B, nano3Dprint is enabling rapid cross-industry growth.
An all three-dimensional (3D)-printed flexible ZnO ultraviolet (UV) photodetector is demonstrated, where the 3D-printing method is used not only for the electrode and photosensitive material but also for creating a substrate. An ultraflat and flexible substrate capable of serving as the backbone layer is developed using a water-dissolvable polymer layer for surface planarization. A two-layered printing followed by surface treatment is demonstrated for the substrate preparation. As mechanical support but flexible, a thick and sparse thermoplastic polyurethane layer is printed. On its surface, a thin and dense poly(vinyl alcohol) (PVA) is then printed. A precise control of PVA reflow using a microwater droplet results in a flexible and extremely uniform substrate. A Cu–Ag nanowire network is directly 3D printed on the flexible substrate for the conducting layer, followed by ZnO for the photosensitive material. Unlike the planar two-dimensional printing that provides thin films, 3D printing allows the electrode to have a step height, which can be made like a dam to accommodate a thick film of ZnO. Photosensitivity as a function of various ZnO thickness values was investigated to establish an optimal thickness for UV response. The device was also tested in natural sunlight along with stability and reliability. Read The Entire Article: All 3D-Printed Flexible ZnO UV Photodetector on an Ultraflat Substrate
*Reproduced from ACS Sens. 2020 5 (4), 1028-1032. DOI: 10.1021/acssensors.9b02544