Subzero fast self-healing and adhesive violet phosphorene incorporated sodium alginate-based hydrogel as strain sensors

Hydrogels are promising materials for wearable electronic devices. However, maintaining the high sensitivity, self-healing, and excellent adhesion of hydrogels at subzero temperatures remains a challenge. The violet phosphorene-polydopamine hybrid (VP-PDA) was introduced into poly (vinyl alcohol)/ethylene glycol/sodium alginate/sodium tetraborate matrix to achieve an anti-freezing hydrogel with high strain sensitivity, extremely high stretchability (3539 %), rapid self-healing capability, and high adhesion even at −60 °C. The hydrogel-based strain sensor has been demonstrated to be significantly enhanced (especially at high strain, GF = 38.83 at 3000 % strain) by the introduction of VP with unique mechanical properties, accurately detecting different strains with quick response (