Fig. 3: The relationship between pyrolysis parameters and dielectric properties.

a Complex permittivity measured in 20, 25, and 30 wt% continuous dielectric frames. The upper left inset indicates the increase in sp² content with increasing pyrolysis temperature. b The imaginary part dielectric constant is fitted with 20 wt% filling, including conductivity loss (ε_c”) and polarization loss (ε_p”). c Schematic representation of the carbon sp² hybridization mode and electrical properties. The red orbitals are π-bonds and the blue orbitals are σ-bonds. The six π-bonds form into one π⁶₆bond. d Results of electron paramagnetic resonance for amorphous carbon. e Results of electrochemical impedance spectroscopy for amorphous carbon. f The resistance measurements result by the four-probe method. g Mulliken charge calculations by density-functional theory (DFT) for sp²-sp³ hybridization models with different sp² bond distributions. The red, blue, and purple numbers indicate the electrons in the corner state, edge state, and bulk state in the sp² region, respectively.