Fig. 5.

a Relative resistance changes of C₁₁T₄A₂₀ sensor as a function of tensile strain. b Relative resistance changes of C₁₁T₄A₂₀ sensor under different tensile strains during 10 successive cycles. c Relative resistance changes under tensile stress with various frequencies. d Response time and release time of C₁₁T₄A₂₀ sensor. e Relative resistance changes under repeated loading–unloading processes with a strain of 50% for 2000 cycles, showing the durability of the sensor. f Relative capacitance changes of C₁₁T₄A₁₅ sensor versus the applied pressure. g Relative capacitance changes of C₁₁T₄A₁₅ sensor under different compressive stress. h Relative resistance changes of C₁₁T₄A₂₀ strain sensor monitoring wrist pulse. Inset shows the photograph of a sensor attached to the wrist. i Phonation when the wearer spoke “Hydrogel,” “Welcome,” and “Thanks.” j Relative resistance changes with bending of finger. k Repeated bending/unbending movements of signal monitoring of the wrist