Mussel-inspired sulfated nanocellulose-mediated conductive nanofiber for thermoelectric and humidity sensing multifunctional applications

The catechol groups of mussel-inspired polydopamine (PDA) act as the active sites to induce in-situ polymerization of 3,4-ethylenedioxythiophene (EDOT) on the surface of tunicate sulfated nanocellulose (TSN) to prepare PEDOT:PDA:TSN (PPTSN) conductive nanofiber with a core-sheath structure. The abundant negative sulfate groups on the surface of TSN endow PPTSN with outstanding dispersion stability. The flexible self-supporting PPTSN nanocomposite films formed by solution casting, inheriting the excellent mechanical properties of the TSN core and electrical conductivity of the PEDOT sheath, exhibit decent thermoelectric properties for thermoelectric material applications. Furthermore, based on the humidity responsiveness of PPTSN, the obtained nanocomposite films have great application prospects in constructing respiratory monitoring and non-contact sensors for sensing human humidity-related behaviors.