• Developed PAM/PEG/SA/S-CNTs-Na dual network hydrogels with high toughness and strong EMI shielding, achieving compressive strength of 19.05 MPa and average EMI SE of 32.92 dB at 3 mm thickness.
• The complete cross-linking strategy and Na+-triggered SA self-assembly significantly enhanced mechanical properties and electrical conductivity of the hydrogels.
• The EMI SE of the optimized hydrogel was 113.21% higher than that of PAM/PEG hydrogels, demonstrating its potential for advanced electromagnetic shielding applications.
• The hydrogel materials offer arbitrary shape adaptability, self-healing ability, and easy modification, making them promising for wearable electronics and aerospace fields.