Paper Title
All-Solution Processable and Highly Efficient Electroluminescent Device; A Study of Structure Optimization

Abstract
The study of Quantum dot (QDs) based light emitting diodes (QLED) is rapidly developing due to the unique physical and optical properties of QDs such is color purity, stability, and solution processibility. Currently, one of the main challenges facing the QLEDs are such as device structure and the low external quantum efficiency. In this study, we primarily optimize the device structure to the simplest one by utilizing the single hole-transporting layer, emissive layer and electron-transporting layer. Extremelyefficient QLED devices were investigated and fabricated by all-solution process, utilizing hybrid hole transport layer (h-HTL). Using the optimized hybrid film as the holes transporter, fascinating QLED devices have been demonstrated on the ITO substrates. Red QLED devices with this h-HTL had prominently increased luminance compared to the devices having multi hole transporting layers. Keywords - Quantum dots, QLED, hole transport materials, electroluminescent materials