Large-Area Inkjet-Printed Flexible Hybrid Electrodes with Photonic Sintered Silver Grids/High Conductive Polymer

Small Methods. 2024 Jan;8(1):e2300638. doi: 10.1002/smtd.202300638. Epub 2023 Sep 19.

Abstract

The field of printed organic electronics has not only made flexible devices accessible but also allows the production process toward a high throughput industrial scale. The current research involves the inkjet-printing of an indium tin oxide-free large-area flexible hybrid electrode compose of a high conductivity organic layer (PEDOT: PSS) as a main electrode and inorganic silver nanoparticles-based grid/film for the auxiliary electrode. The current bottleneck in the roll-to-roll production of printed electronics is the time required for the conductive inks to dry and sinter. Flash sintering is used to dry nano-silver conductive ink to 77.6 m Ω □-1 sheet resistance in <20 ms, the quickest annealing procedure, without damaging flexible substrates. Flexible organic light-emitting diodes (OLEDs) are created with a large active area (500 mm2 ) to demonstrate the efficacy of the flexible hybrid electrodes and the excellent bending stability (4 mm bending radius) of OLEDs. Maximum current efficiency of 19.58 cd A-1 and a maximum luminescence of 8708 cd m-2 at a low turn-on voltage of 3.1 V for the small-area (16 mm2 ) OLEDs are achieved. This method is promising for reducing indium consumption and paving the way for creating new high throughout hybrid electrodes for large-area flexible printed electronics.

Keywords: ITO-free; flexible OLEDs; inkjet printing; large-area; photonic sintering; silver NPs ink.