Dual optimization of dielectric loss and electromagnetic wave absorption in lunar-like porous carbons via N, Cl co-doping

Heteroatom doping, by synergistically regulating defect concentration, dielectric loss factors, and conductive behavior, enables precise tailoring of the electromagnetic response in carbon-based materials. In this study, lunar-like nitrogen (N), chlorine (Cl) co-doped porous carbon microspheres (N, Cl-PCMs) were fabricated via a hydrothermal–pyrolysis method using a self-synthesized N, Cl-containing compound as the dopant. By adjusting the doping level, controllable morphology and tunable electromagnetic responses were achieved. The heteroatoms create heterogeneous interfaces and defects that act as efficient polarization sites, thereby promoting polarization relaxation while optimizing the conductive network for improved conductive loss. Multiple attenuation mechanisms synergistically enable optimized impedance matching and efficient electromagnetic attenuation. The optimal N, Cl-PCMs-2 exhibits remarkable electromagnetic wave absorption (EMWA) performance, with a minimum reflection loss (RL min ) of −56.00 dB at 2.99 mm and an effective absorption bandwidth (EAB) widened to 5.44 GHz at 2.22 mm. Radar cross-section (RCS) simulations further demonstrated a maximum reduction of 27.45 dB m 2 at 0°, confirming its promise for multiband electromagnetic stealth. This work provides new insight into the multiscale structure of biomass-derived carbons for green, high-performance electromagnetic absorption absorbers.