Enhancing thermal conductivity and chemical protection of bacterial cellulose/silver nanowires thin-film for high flexible electronic skin

Silver nanowires (AgNWs) thin films have emerged as a promising next-generation flexible electronic device. However, the current AgNWs thin films are often plagued by high AgNWs-AgNWs contact resistance and poor long-term stability. Here, to enhance the AgNWs stability on the surface of bacterial cellulose (BC), a novel flexible high conductivity thin-film was prepared by spin-coating a layer of polyvinyl alcohol (PVA) on the BC/AgNWs (BA) film. Firstly, BC film with high uniformity to better fit the AgNWs was obtained. It is observed that inadequately protected AgNWs can be corroded when AgNWs together with PVA were attached to the BC surface (BAP film), Yet, a layer of PVA was spin-coated on the surface of BA film, the BC/AgNWs/spin-coated 0.5 % PVA (BASP) thin-film (10.1 μm) exhibits that the PVA interfacial protective layer effectively mitigated the intrinsic incompatibility of BC with AgNWs as well as external corrosion (Na2S for 3 h) and immobilization of AgNWs, thus having a low conductive sheet resistance of 0.42 Ω/sq., which was better than most of the AgNWs-containing conductive materials reported so far. In addition, the resistance of the BASP thin-film changed little after 10,000 bending cycles, and the conductivity remained stable over BC directly immersed in 0.5 % PVA/AgNWs. This "soft" conductive material can be used to manufacture a new generation of electronic skin.