Black phosphorus modified wearable textile with excellent flame retardancy for personal thermal management and motion detection

A sandwich structure composite phase change textile material (CPCTM) was prepared by electrospinning. In the top and bottom layers, black phosphorus nanosheets (BPNs) was compounded into polyacrylonitrile (PAN). In the middle layer, the phase change thermal energy storage material polyethylene glycol (PEG) was well encapsulated by polyvinyl alcohol (PVA). By designing multilayer structure, the CPCTM exhibited excellent intensity with the tensile strength 62.65 MPa and the elongation at break 1176 %. The melting temperature and the crystallization temperature of CPCTM were 54.36 ℃ and 31.43 ℃ which were lower than pure PEG (55.87 ℃ and 35.55 ℃). The lower melting and crystallization temperature facilitated the storage of heat in CPCTM for body thermal management. Compared with that of pure PAN, the total heat release and total smoke production of the PAN@BP were respectively descended by 33.05 % and 80.43 %. During combustion, transfer of combustible gases and heat were hindered due to the formation of the expanded char layer by the BPNs. Meanwhile, the CPCTM showed excellent flexibility and ability of motion detection, which had broad application prospects in the fields of wearable electronic devices.