Conductive hydrogels have promise in a range of applications, but most existing conductive hydrogels’ susceptibility to water loss and poor freeze resistance limit their use in extreme environments such as low temperatures. Here, we report a mixed ionic-electronic conductive PDA/PAAM/AgNO3/ILs gel through the synergistic action of Ag+ and ionic liquids (ILs). This gel enhances adhesion by incorporating catechol-modified sodium alginate into the crosslinked polyacrylamide network structure, achieving adhesion strengths ranging from 19.26 to 26.77 KPa. The combined use of AgNO3 and ILs enhanced the conductive and mechanical properties of the gel. The conductivity of the PDA/PAAM/AgNO3/ILs gels increased from 0.83 mS/cm to 47.16∼49.93 mS/cm, while the tensile strength rose from 98.80 KPa to 154.84∼193.72 KPa. The incorporation of ILs also endows the PDA/PAAM/AgNO3/ILs gels with low volatility and freeze resistance, enabling a broad temperature response range. Comparing the three distinct PDA/PAAM/AgNO3/ILs gels, the PDA/PAAM/AgNO3/EM gel demonstrated the most favorable electrical conductivity and mechanical properties, providing valuable insights for the application of ILs in hydrogel systems. This research addresses the application needs of hydrogels in flexible sensor electronics, enhancing reliability and safety for flexible electronics, including low-temperature environments.
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