Microwave-assisted immobilized silver nanowires on arbitrary substrates: an eco-friendly technique for next-generation transparent, flexible and robust electronics

Abstract

Silver nanowires (AgNWs) are well-known as promising candidates to replace indium tin oxide (ITO) in transparent flexible electronics (TFEs). However, the poor adhesion of AgNWs to the substrates causes several issues that seriously prevent their application in TFEs. Herein, a novel method is developed to synchronously enhance AgNW adhesion to substrates and reduce resistivity without sacrificing transparency by using cysteamine (CYS). CYS is a biocompatible molecule that can be used to decorate polymeric substrates with the assistance of microwave (MW) irradiation, leading to the immobilization of NWs onto a substrate with covalent bonds. Since processing with MW energy is a green and highly efficient technique, the proposed method offers advantages, including reaction time reduction, improved yields, increased product purities, selectivity improvement, and simple procedures. The sheet resistance of the NW film significantly decreases from 143.36 to 12.37 Ω sq⁻¹ with a non-uniformity factor of 1.4% and shows a 94% transmittance at 550 nm. The NW networks demonstrate strong adhesion to the substrates, maintaining conductivity after 10 000 bending cycles. The obtained electrodes show brilliant optical, electrical, and bending performances. The utility of PET-CYS-NWs was confirmed by LED array and biosensor demonstrations. This general approach can be expanded in a straightforward manner to various polymeric substrates and can open up pathways for TFEs.