Ultrathin Wood‐Derived Conductive Carbon Composite Film for Electromagnetic Shielding and Electric Heating Management

Abstract

Recently, wood‐based composites have absorbed widespread concern in the field of electromagnetic interference (EMI) shielding due to their sustainability and inherent layered porous structure. The channel structure of wood is often used to load highly conductive materials to improve the EMI shielding performance of wood‐based composites. However, there is little research on how to use pure wood to prepare ultrathin EMI shielding materials. Herein, ultrathin veneer is obtained by cutting wood in parallel to the annual rings. Then, carbonized wood film (CWF) is prepared by a simple two‐step compressing and carbonization. The specific EMI shielding effectiveness (SSE/t) of CWF‐1200 with an ultrathin thickness (140 µm) and high electrical conductivity (58 S cm−1) can reach 9861.41 dB cm2 g−1, which is much higher than other reported wood‐based materials. In addition, the zeolitie imidazolate framework‐8 (ZIF‐8) nanocrystals are grown in situ on the surface of the CWF to obtain CWF/ZIF‐8. CWF/ZIF‐8 exhibits an EMI shielding effectiveness (SE) of up to 46 dB and an ultrahigh SSE/t value of 11 330.04 dB cm2 g−1 in X band. In addition, the ultrathin CWF also shows an excellent Joule heating effect. Therefore, the development of ultrathin wood‐based film provides a research basis for wood biomass to replace traditional non‐renewable and expensive electromagnetic (EM) shielding materials.

Multifunctional Conductive Material Based on Intelligent Porous Paper Used in Conjunction with a Vitrimer for Electromagnetic Shielding, Sensing, Joule Heating, and Antibacterial Properties

“…The synergy of the above three aspects gives the CPPA-60 composite excellent EMW shielding performance. In addition, in order to highlight the excellent electromagnetic shielding performance of CPPA-60 composites, as shown in Figure S21 and Table S1, we comprehensively compare the relationship between the shielding capacity and thickness of CPPA-60 composites and EMW shielding materials reported in previous studies. − The CPPA-60 composite material demonstrates an impressive EMW shielding capacity ranging from 51.3 to 96.4 dB, with corresponding thicknesses between 0.17 and 0.51 mm. It is evident that CPPA composites exhibit outstanding EMW performance even at lower thicknesses.…”

High Value Utilization of Waste Wood toward Porous and Lightweight Carbon Monolith with EMI Shielding, Heat Insulation and Mechanical Properties

“…The densities of balsa wood, basswood and beech after carbonization at 1000 °C are 200, 230 and 330 mg cm −3 , respectively. Obviously, the density of WC materials meets the requirements of lightweight electromagnetic interference shielding material [ 29 , 33 , 41 ].…”

“…In addition, the lightweight of EMI shielding materials is very important in the application fields of aerospace, portable and wearable electronic devices. Obviously, the material density has a great impact on the shielding performance of EMI shielding materials [ 29 , 33 ]. Therefore, it is necessary to investigate the EM shielding properties of wood with different densities.…”

Carbonized Wood/Nickel Nanoparticle Composites with Oriented Channels for Enhanced Electromagnetic Interference Shielding

“…Ni and sp 3 carbon can form C–Ni bonds due to the affinity of nickel for carbon. The highest Ni content in the CW/Ni-0° leads to the formation of more C–Ni bonds, facilitating the conversion of sp 3 bonds to sp 2 bonds in the carbon matrix to increase graphitization. , The I D / I G value decreases from 0.91 of CW to 0.58 of CW/Ni-0°, implying an increase in graphitization of CW/Ni-0° . Furthermore, the graphite crystallite sizes ( L a ) of CW, CW/Ni-90, CW/Ni-60, CW/Ni-30, and CW/Ni-0° are 21.2, 22.9, 25.3, 30.6, and 33.3, respectively, showing a tendency to increase crystallinity (Figure c) …”

“…18,33 The I D /I G value decreases from 0.91 of CW to 0.58 of CW/Ni-0°, implying an increase in graphitization of CW/Ni-0°. 34 respectively, showing a tendency to increase crystallinity (Figure 5c). 35…”