Breaking the impedance–attenuation trade-off in triply periodic minimal surface ceramics via hierarchical carbon nanowires networks with load-bearing capability

Architectured ceramic absorbers are expected to simultaneously withstand mechanical loading and attenuate electromagnetic (EM) waves over a broad frequency range; however, achieving an optimized balance between structural integrity, impedance matching, and dielectric loss remains a major obstacle. In this work, a rhombus-like triply periodic minimal surface (TPMS) SiOC ceramic was fabricated and subsequently decorated with carbon nanowires (CNWs) along the ridge regions through an integrated process involving vat photopolymerization, polymer-derived ceramics (PDCs) conversion, chemical vapor deposition (CVD), and thermal treatment. This structural design establishes a hierarchical conductive–dielectric framework, where the TPMS geometry and ridge-oriented CNWs distribution collectively regulate mechanical and EM responses. The TPMS skeleton provides continuous load-transfer pathways while promoting EM wave penetration and multiple reflections, whereas the CNWs network introduces conductive channels and additional polarization interfaces to enhance EM dissipation. With a CNWs content of 3.95 wt%, the CNWs/SiOC ceramic delivers a minimum reflection loss (RL min ) of −54.66 dB and an effective absorption bandwidth (EAB) of 6.9 GHz at 3.35 mm. CST-based EM simulations confirm that the CNWs/SiOC architecture maintains a favorable dielectric response from 4 to 18 GHz, supporting broadband attenuation. In addition to its absorption capability, the sample containing 7.75 wt% CNWs reaches a compressive strength of 21.84 MPa, indicating the contribution of the architectured ceramic framework and ridge-oriented CNWs reinforcement to mechanical robustness. The improved attenuation is associated mainly with localized electric-field enhancement near the ridges, conductive dissipation through the CNWs network, and polarization loss generated by heterogeneous interfaces. These findings demonstrate that the ridge-oriented CNWs modification of architectured SiOC ceramics provides an effective strategy for the integrated realization and simultaneous optimization of load-bearing capability and broadband EM wave absorption. Download: Download high-res image (349KB) Download: Download full-size image