Role of Polymeric Metal Nucleation Inducers in Fabricating Large-Area, Flexible, and Transparent Electrodes for Printable Electronics

The advent of special types of transparent electrodes, known as ultrathin metal electrodes, opens a new avenue for flexible and printable electronics based on their excellent optical transparency in the visible range while maintaining their intrinsic high electrical conductivity and mechanical flexibility. In this new electrode architecture, introducing metal nucleation inducers (MNIs) on flexible plastic substrates is a key concept to form high-quality ultrathin metal films (thickness approximate to 10 nm) with smooth and continuous morphology. Herein, this paper explores the role of polymeric MNIs in fabricating ultrathin metal films by employing various polymers with different surface energies and functional groups. Moreover, a scalable approach is demonstrated using the ionic self-assembly on typical plastic substrates, yielding large-area electrodes (21 x 29.7 cm(2)) with high optical transmittance (>95%), low sheet resistance (< 10 Omega sq(-1)), and extreme mechanical flexibility. The results demonstrate that this new class of flexible and transparent electrodes enables the fabrication of efficient polymer light-emitting diodes.