Phase separation in intrinsically stretchable electronics: Mechanisms, functions and applications

Stretchable electronics made from intrinsically stretchable materials have garnered a great deal of attention for future human-friendly electronic applications due to their exceptional mechanical compatibility with soft tissues. However, intrinsically stretchable materials with homogeneous conductive networks often compromise electrical performance to achieve stretchability. By employing phase separation strategies that rationally separate conductive networks and stretchable matrix, the electrical performance of these electronics can be significantly improved without sacrificing stretchability. Meanwhile, phase separation can also be applied to produce diverse porous microstructures, endowing stretchable electronics with desirable functionalities, such as strain buffering, heightened ion transfer, air permeability, and passive cooling. In this article, we reviewed the recent advancements in stretchable electronics fabricated through phase separation strategies. After delving into the driving mechanisms behind various phase-separation strategies, we showcased representative examples to highlight the versatile functionalities of phase-separated structures in stretchable electronic components and devices. Furthermore, we discussed the current challenges and prospects of utilizing phase separation strategies for next-generation intrinsically stretchable electronics.