Lignocellulose nanofibril/gelatin/MXene composite aerogel with fire-warning properties for enhanced electromagnetic interference shielding performance.

[Display omitted] • Phosphated lignocellulose nanofibrils were combined with MXene and gelatin; • The aerogel exhibited excellent fire retardancy with fire-warning performance; • Performance of electromagnetic interference shielding also achieved highly. Lightweight electromagnetic interference (EMI) shielding material with environment-friendly and high fire-safe has imperative practical significance in civil electronic devices. Herein, a distinct strategy was proposed to integrate phosphated lignocellulose nanofibrils (PLCNFs), gelatin, and MXene into a hybrid composite aerogel (PGM aerogel) with ultralight weight and high porosity. Due to the synergistic flame retardant effect of the ternary mixture, PGM aerogel exhibited excellent fire retardancy, whose dramatical changes in electronic resistance was supposed to achieve a short fire-warning signal (∼1 s). The limiting oxygen index (LOI) was as high as 32 % and the peak heat release rate (PHRR) was relatively as low as 30.1 W/g. Furthermore, the aerogel also displayed great specific EMI shielding effectiveness (SE) of SSE/t (14230 dB cm2 g−1) at 8.2 GHz. Therefore, this PGM aerogel can be a potential candidate in both EMI shielding and fire-warning fields. [ABSTRACT FROM AUTHOR]