Comparative study on pyrolytic transformation mechanism of ANFs-derived carbon membrane for electromagnetic interference shielding application

Selecting suitable precursor and exploring controllable carbonization process is crucial to carbon materials, especially for carbon-based material in electromagnetic interference shielding application. However, carbon materials are primarily used in the forms of powders, which remains big challenge in developing continuous ones. Herein, large-scale aramid nanofibers (ANFs)-derived carbon membrane was developed for the first time. Influence of pyrolysis temperature on chemical constitution and crystalline structure during carbonization process was investigated. The results showed that the decomposition stage of ANFs freestanding membrane begun at ~ 474 °C, while the reconstruction stage begun at ~ 600 °C. Besides, the rupture of amide bonds occurred around 500 °C, which was validated by disappearance of C=O groups. Moreover, the declining integrated intensities I D / I G , and the sharp rising electrical conductivity of demonstrated progressive aromatization and ring condensation. In addition, the microgrooves with an average diameter of ~ 40 nm were formed during the carbonization. Subsequently, the ANFs-derived carbon membrane exhibited superior conductivity (123.8 S cm −1 ) and electromagnetic shielding effectiveness value of 16 dB (X band) with thickness of 28 μm. This work provided feasible strategy in fabricating carbon-based membrane for advanced electronic devices.