Advanced flame-retardant melamine foam with ultra-sensitivity and prolonged fire warning, featuring smart device-integrated graphene oxide/attapulgite nano-coating

Enhancing flame retardancy and fire-warning capabilities of thermal insulation materials used in building external walls is crucial for ensuring fire safety as well as guarding people's lives and assets. Herein, we have developed an environmentally friendly nano-coating that possesses flame-retardant and early-warning properties by integrating graphene oxide (GO) and attapulgite (ATP) onto melamine foam (MF) through a layer-by-layer self-assembly method (LBL). The GO-ATP-MF composite demonstrates a rapid response to flame (<1 s) due to GO's thermally induced reduction. Additionally, ATP's synergistic flame-retardant effects on both gas and condensed phases contribute to outstanding flame retardancy, enabling an enduring fire alarm duration (>1330 s). The warning duration time of this composite surpasses the majority of GO-based fire-warning nano-coatings reported to date. Moreover, incorporating a Bluetooth wireless transmission system facilitates real-time fire information sharing among smart devices, thereby optimizing fire signal transmission efficiency. Thus, this study advances GO-based flame-retardant nano-coatings and devices with high sensitivity and prolonged fire-warning capabilities, providing an innovative idea to enhance the fire safety of MF as a thermal insulation material.