Hierarchically ordered porous g-C3N4 framework supported Ni nanoparticles for fire safety and thermal stealth application

Abstract

It remains a challenge to develop multi-functional flame retardants to satisfy ever-growing demands in complex working environments. Herein, hierarchically ordered porous g-C3N4 framework decorated with nickel nanocrystals (Ni/MmCNs) was innovatively designed. Transmission electron microscopy images confirm the distinct 3D interconnected macro-/mesoporous structure and dispersed Ni nanoparticles on the framework, which are the keys to realizing the multi-functions of flame retardancy, thermal stealth, and mechanical performance enhancement. The cone calorimeter and bending tests results show that 5 wt% addition of Ni/MmCNs not only endows the epoxy nanocomposites with better fire safety including the delay of ignition time (tignition) and the reduction of heat and smoke release but also enhances the flexural strength compared with the pure epoxy. In addition, the Ni/MmCNs exhibits enhanced thermal insulation and infrared shielding functions, as evidenced by lower upper surface temperature under infrared detection.