Soft electronics have attracted enormous attentions in the growing eld of bioelectronic integration. Among the various material choices, hydrogels are of particular interest due to their intrinsic similarities with biological tissues. However, challenges still remain for the fabrication of hydrogel electronics, especially those featuring 3D form-factors to conform with the complex biological environment. Here we develop a set of materials which allows for the rst time, fully 3D printing of soft electronics featuring soft circuits with arbitrary form factors embedded within soft hydrogel matrix. We design an embedded 3D printing (EM3DP) technology with a curable, ultra-soft (< 5 kPa) and stretchable (λ ~ 18) hydrogel matrix by employing packed hydrogel microparticles possessing a secondary crosslinking capability, and a highly conductive (~1.4×10 3 S/cm) Ag-hydrogel composite with a segregated conductive network structure. We fabricate various hydrogel-based passive electronics and demonstrate their functionalities. Furthermore, discrete surface-mount components can be readily picked-and-placed at any pre-determined position within the hydrogel matrix and connected with printed passive structures through a highly automated process, thereby greatly expanding the soft electronic functionalities. This work demonstrates the versatility of EM3DP for the future manufacturing of hydrogel-based 3D electronics.

One dimensional (1D) light-emitting fibres emerge as a top candidate for flexible and stretchable displays, enabling the miniaturization of device architectures and integration of different optoelectronic materials and components for...

New manufacturing strategies toward customizable energy storage devices (ESDs) are urgently required to allow structural designability for space and weight-sensitive electronics. Besides the macroscopic geometry customization, the ability to fine-tune the ESD internal architectures are key to device optimization, allowing short and uniform electrons/ions diffusion pathways and increased contact areas while overcoming the issues of long transport distance and high interfacial resistance in conventional devices with planar thick electrodes. ESDs with 2D or 3D electrodes filled with liquid or gel-like electrolyte have been reported, yet they face significant challenges in design flexibility for 3D ESD architectures. Herein, a novel method of assembling ESDs with the ability to customizing both external and internal architectures via digital light processing (DLP) technique and a facile sequential dip-coating process is demonstrated. Using supercapacitors as prototype device, the 3D printing of ESDs with areal capacity of 282.7 mF cm −2 which is higher than a reference device with same mass loading employing planar stacked configuration (205.5 mF cm −2 ) is demonstrated. The printed devices with highly customizable external geometry conveniently allow the ESDs to serve as structural components for various electronics such as watchband and biomimetic electronics which are difficult to be manufactured with previously reported strategies.

Soft electronics have attracted enormous attentions in the growing field of bioelectronic integration. Among the various material choices, hydrogels are of particular interest due to their intrinsic similarities with biological tissues. However, challenges still remain for the fabrication of hydrogel electronics, especially those featuring 3D form-factors to conform with the complex biological environment. Here we develop a set of materials which allows for the first time, fully 3D printing of soft electronics featuring soft circuits with arbitrary form factors embedded within soft hydrogel matrix. We design an embedded 3D printing (EM3DP) technology with a curable, ultra-soft (< 5 kPa) and stretchable (λ ~ 18) hydrogel matrix by employing packed hydrogel microparticles possessing a secondary crosslinking capability, and a highly conductive (~1.4×103 S/cm) Ag–hydrogel composite with a segregated conductive network structure. We fabricate various hydrogel-based passive electronics and demonstrate their functionalities. Furthermore, discrete surface-mount components can be readily picked-and-placed at any pre-determined position within the hydrogel matrix and connected with printed passive structures through a highly automated process, thereby greatly expanding the soft electronic functionalities. This work demonstrates the versatility of EM3DP for the future manufacturing of hydrogel-based 3D electronics.