Schematic diagram showing overall processing of non-covalently FGO

TEM images of a GO and b FGO. c XRD patterns and d Raman spectra of GO and FGO

TGA profiles of GO and FGO under nitrogen atmosphere

a Schematic diagram of LBL assembly of FGO/PEI bilayers on PVA film. b SEM top-view images and c cross-section images of the coated sample. d Photographs showing excellent flexibility of the coated PVA film

a UV-Vis spectra of GO-based multilayers deposited on PVA substrate and b absorption intensity at 231 nm as a function of bilayer number

a TGA profiles of neat PVA, PVA/FGO, and PVA coated with different FGO-based layers. Schematic depicting degradation processes of b pure PVA and c coated PVA

a HRR and b THR profiles of pure PVA, PVA/GO, and self-assembled FGO-coated PVA with different numbers of bilayers

Snapshots of flame treatment of a PVA film, b PVA/FGO composite film, and c LBL-assembled FGO-coated PVA film with 10 bilayers with respect to time in 9 s. d Raman spectra of PVA coated with different self-assembled (FGO/PEI) bilayers after flame treatment. SEM images of external surfaces of FGO-based coating residue with e 10, f 20, and g 30 bilayers and internal surfaces of FGO-based coating residue with h 10, i 20, and j 30 bilayers. The insert shows XPS spectra of external and internal surfaces of FGO-based coating residue

Scheme of the flame-retardant behaviors of a PVA/FGO composite and b FGO multilayer-coated PVA

Snapshots of flame treatment of PVA sheet coated with 30 LBL-assembled bilayers based on a GO and b FGO with respect to time in 40 s. c Photographs showing morphology of films before and after flame treatment. d Schematic diagram of char structure of FGO-based residue layer