Biomimetic construction of highly durable nacre-like MoS2 bio-nanocomposite coatings on polyacrylonitrile textile for intumescent flame retardation and sustainable solar-thermal-electricity conversion

Abstract A highly durable bifunctional bio-nanocomposite coating is constructed on polyacrylonitrile (PAN) textile by using tannic acid (TA) modified cellulose nanofiber (TA-CNFs) and MoS2 nanosheets (TA-MoS2). The interfacial chelating of TA with Fe3+ drives the alternative assembly of "brick-and-mortar" TA-CNFs/TA-MoS2 nanocoating on PAN textile, while the chemical crosslinking between TA and borate endows the nanocoating with excellent durability. The PAN textile with 7.34 wt% weight imparts significantly improved thermal stability (increased by 40.6 °C) and excellent intumescent flame-retardant characteristic to PAN textile, enabling a 68%, 79% reduction in the peak heat release rate and total smoke production, respectively. The dramatic suppressions on CO and HCN releases are observed from TG-IR test. Importantly, after washing 80 times, the LOI value of PAN textile only decreases from 34.8% to 30.1%. Moreover, this bio-composite coating exhibits sustainable potential for nonhazardous conversion from solar energy to thermoelectricity power. Under the simulated sunlight, the voltage output of the PAN-coupled thermoelectric generator (102.4 mV) are 4 times to that of a blank one (25.6 mV).