65‐6: Control of Oxygen Vacancy in ZnO Nanoparticles Electron Transport Layer by Intense Pulsed‐Light Post‐Treatment Under Fabrication of Ink‐Jet Printed QLEDs

Previously, we reported that the charge injection balance in spin‐coated quantum‐dot light‐emitting diodes (QLED) was achieved by controlling the current density characteristics via filling of the oxygen vacancies in Zinc oxide (ZnO) nanoparticles (NPs) through intense‐pulsed light (IPL) post‐treatment [1]. In this work, we investigated the IPL posted‐treatment induced charge balance and stability of device performance prepared by the ink‐jet printed QLED. Oxygen vacancies (Vo) in the ZnO wurtzite structure were filled with oxygen by IPL post‐treatment process in the air atmosphere, and the ink‐jet printed QLED performance remained stable during the 8 day measurement period. The current efficiency (CE) and external quantum efficiency (EQE) characteristics of ink‐jet printed QLED showed a tendency to stabilize from the 2 nd day, and the performance of the device were 34122 cd/m 2 luminance, 7.3513 cd/A CE, and 1.943 % EQE.