Hollow LDH cage covering with ultra-thin MXenes veil: Integrated micro-nano structure upon heat release suppression and toxic effluents elimination for polymer

The using of epoxy resin (EP) has been compromised by its high fire hazard. In this context, MXenes nanoflakes have been preferred as flame retardant, considering its merits in suppressing heat as well as toxic gases emission. Nevertheless, it is difficult to achieve the desired flame retardancy efficiency when the MXenes dosage is low. Thus far, the development of nanostructure based on MXenes with high flame retardant capacity has been seldom investigated. In this contribution, we have designed a strongly-coupled micro-nano structure based on hollow LDH covering with ultra-thin MXenes veil (MX@H-LDH) via assembly strategy. When loading 5.0 wt% MX@H-LDH, peak heat release rate, total heat release, peak CO production rate and total CO production can be reduced by 54.6%, 37.5%, 47.4%, 63.6%, accordingly. Meanwhile, the prominence of MX@H-LDH in inhibiting the release of heat is confirmed via the comparison with previous works. The curbed toxic CO, NO and HCN releases are also discerned in gases phase analysis. Moreover, it is satisfactory to find that the using of MX@H-LDH strengthens the mechanical capability, assigned to the mechanical interlocking action. Briefly, this work can be instructive for the design of novel MXenes-based nanostructure, mining its potentials in polymer composites with high performance.