▎ 摘　　要

Solution-processed composite hole injection interfacial layer (HIL) of MoOx-doped graphene oxide (GO+MoOx) is facilely fabricated. Using GO+MoOx HIL, we demonstrate highly efficient tris(8-hydroxy-quinolinato)aluminum-based organic light-emitting diodes with maximum luminous efficiency of 8.6cdA(-1), power efficiency of 5.7lmW(-1), and external quantum efficiency of 3.5%, which have been enhanced by 41.0% (75.5%), 39.0% (96.6%), and 40.0% (75.0%), respectively, in comparison with the counterpart using simple HIL of MoOx (GO). Atomic force microscopy and X-ray/ultraviolet photoelectron spectroscopy measurements show GO+MoOx behaving superior film morphology and extra electronic properties such as enhanced surface work function. Current-voltage characteristics and impedance spectroscopy of hole only cells elucidate that GO+MoOx substantially promotes hole injection and thus accounts for excellent device performance. Our results pave a way for advancing organic electronic devices with solution process as well as boosting GO application.