Lignin-based porous carbonization materials with regular topology arrangement for efficient electromagnetic interference shielding and electrothermal conversion

The electromagnetic pulse attenuation mechanism based on multiple internal reflection and absorption can effectively improve the electromagnetic shielding performance. In this study, alkali lignin (AL) was used as the main raw material, polyvinyl alcohol (PVA) as the long chain binder, and NiCl 2 ·6 H 2 O as the shielding reinforcement material. Through directional freeze drying and high temperature carbonization, lignin-based polyporous carbonization materials with high efficiency electromagnetic shielding were constructed. The chelation of Ni 2 + , PVA and AL hydroxyl groups promotes the cross-linking of hydrogen and covalent bonds to form an organic-inorganic cross-linking network, effectively weakens the phenomenon of crystal nucleus aggregation after polymer carbonization to facilitate the construction of regular topology arrangement, and the doping of Ni nanoparticles enhances the conductivity of the composites (435.7 S/m). It is worth noting that the regularly arranged electric carbon network of CAPNi 0.5 extends the reflection and absorption path of electromagnetic waves, multiple reflection and absorption within the structure give the system ultra-high electromagnetic interference shielding capability (109 dB, absorption loss of 89.3 %). In addition, CAPNi 0.5 shows excellent joule heating performance and can quickly reach and stabilize at 184 ℃ within 50 s under a low voltage of 1.5 V. This work provides a new construction strategy for multiple electromagnetic wave attenuation mechanism and biomass sustainable environmental protection. • The chelation of Ni 2+ , PVA and AL promotes the formation of organic-inorganic cross-linking network. • This network promotes the construction of regular arrangement structure. • The system exhibits ultra-high electromagnetic interference shielding capability.