Biodegradable electronics are considered as an important bio‐friendly solution for electronic waste (e‐waste) management, sustainable development, and emerging implantable devices. Elastic electronics with higher imitative mechanical characteristics of human tissues, have become crucial for human‐related applications. The convergence of biodegradability and elasticity has emerged a new paradigm of next‐generation electronics especially for wearable and implantable electronics. The corresponding biodegradable elastic materials are recognized as a key to drive this field toward the practical applications. The review first clarifies the relevant concepts including biodegradable and elastic electronics along with their general design principles. Subsequently, the crucial mechanisms of the degradation in polymeric materials are discussed in depth. The diverse types of biodegradable elastomers and gels for electronics are then summarized. Their molecular design, modification, processing, and device fabrication especially the structure–properties relationship as well as recent advanced are reviewed in detail. Finally, the current challenges and the future directions are proposed. The critical insights of biodegradability and elastic characteristics in the elastomers and gel allows them to be tailored and designed more effectively for electronic applications.

Although highly desired, it is difficult to develop mechanically robust and room temperature self‐healing ionic liquid‐based gels (ionogels), which are very promising for next‐generation stretchable electronic devices. Herein, it is discovered that the ionic liquid significantly reduces the reversible reaction rate of disulfide bonds without altering its thermodynamic equilibrium constant via small molecule model reaction and activation energy evolution of the dissociation of the dynamic network. This inhibitory effect would reduce the dissociated units in the dynamic polymeric network, beneficial for the strength of the ionogel. Furthermore, aromatic disulfide bonds with high reversibility are embedded in the polyurethane to endow the ionogel with superior room temperature self‐healing performance. Isocyanates with an asymmetric alicyclic structure are chosen to provide optimal exchange efficiencies for the embedded disulfide bonds relative to aromatic and linear aliphatic. Carbonyl‐rich poly(ethylene‐glycol‐adipate) diols are selected as soft segments to provide sufficient interaction sites for ionic liquids to endow the ionogel with high transparency, stretchability, and elasticity. Finally, a self‐healing ionogel with a tensile strength of 1.65 ± 0.08 MPa is successfully developed, which is significantly higher than all the reported transparent room temperature self‐healing ionogel and its application in a 3D printed stretchable numeric keyboard is exemplified.

Electrotherapy is a promising tissue repair technique. However, electrotherapy devices are frequently complex and must be placed adjacent to injured tissue, thereby limiting their clinical application. Here, we propose a general strategy to facilitate tissue repair by modulating endogenous electric fields with nonadjacent (approximately 44 mm) wireless electrotherapy through a 3D-printed entirely soft and bioresorbable triboelectric nanogenerator based stimulator, without any electrical accessories, which has biomimetic mechanical properties similar to those of soft tissue. In addition, the feasibility of using the stimulator to construct an electrical double layer with tissue for nonadjacent wireless electrotherapy was demonstrated by skin and muscle injury models. The treated groups showed significantly improved tissue repair compared with the control group. In conclusion, we developed a promising electrotherapy strategy and may inspire next-generation electrotherapy for tissue repair.

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