Fire/Acid/Alkali‑Resistant Aramid/Carbon Nanofiber Triboelectric Nanogenerator for Self‑Powered Biomotion and Risk Perception in Fire and Chemical Environments

Casualties are frequent in high-risk environments,particularly in high-risk chemical and high-temperature fire environments,due to improper protection or accidents.While wearable sensors can offer real-time biomechanical monitoring in fire and chemical environments,they cause discomfort,contain toxic heavy metals,and lack resistance to fire and acid/alkali.Herein,a facile approach to fabricating metal-free fire/acid/alkali-resistant poly(m-phenylene isophthalamide)fiber and carbon nanofiber composite triboelectric nanogenerator(PMIA/CNF-TENG)was demonstrated.The PMIA/CNF-TENG shows the advantages of textile construction including flexibility,waterproofing,and moisture permeability.It also exhibits unique functions,such as ultrahigh fire/temperature resistance,strong acid and alkali protection,the ability to monitor human signals in real time with self-power,handwritten input for danger signals,and sudden risk perception.The PMIA/CNF-TENG pos-sessed an open-circuit voltage(V_(OC))retention rate of 96.8%even at 250°C,thereby showing considerably higher thermal stability than conventional flame-retardant TENGs.When moved from room temperature to a simulated fire environment,the biomotion-generated VOC increased by 136.7%for bending the elbow and by over 900%for hand input,indicating good fire-sensing capability.In addition,output signal strength by solid-liquid contact depended on the solution type and cor-responded to the laws—NaOH>HNO_(3)>H_(2)SO_(4)>H_(2)O,indicating potential applications in chemical splash detection and active acid-alkali liquid identification.Moreover,the PMIA/CNF-TENG could be built into wireless intelligent sensing systems to achieve remote biomotion and risk perception.