Research progress on moisturizing and anti-freezing conductive hydrogels in flexible electronics

Conductive hydrogel is one novel flexible material with outstanding conductivity, flexibility and skin-friendliness, which has made great progress in flexible electronics recently. However, similar to traditional hydrogels, the applications of conductive hydrogels in extreme environments still face limitations. To extend the operational temperature range of hydrogels, some researchers have paid attention to the dehydration/freezing behavior of hydrogels, resulting in the successful design and fabrication of a series of hydrogels with moisturizing and anti-freezing properties. In this review, the strategies for improving the temperature tolerance of hydrogels are summarized, and the potential mechanisms of moisturizing and anti-freezing hydrogels are described in detail. Furthermore, the applications of environmentally stable hydrogels in the field of flexible electronics are discussed, including motion perception, health monitoring, intelligent recognition and human-computer interaction. Additionally, the opportunities and challenges faced by the moisturizing and anti-freezing hydrogels are deliberated, with the objective of stimulating innovative approaches towards weather-resistant hydrogel development. By advancing the development of modern hydrogels with excellent comprehensive performance, the aim is to facilitate their broader practical application in extreme environments.