Improved Efficiency for Silicon‐Based Perovskite Light‐Emitting Diodes via Interfacial Hydrophilic Modification

Abstract Silicon‐based perovskite light emitting diodes (PeLEDs) possess great potential in the fields of silicon‐based display devices and on‐chip light sources. However, the contact problem between metal electrodes and solution‐processed hole/electron transport layers generally deteriorates the device performance. Here, an interfacial hydrophilic modification strategy is proposed to solve the contact issue between the metal electrode and the hole transport layer poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) in Si‐based PeLEDs. By introducing an ultrathin NiO x buffer layer on the hydrophobic Au bottom electrode, the morphology of the PEDOT:PSS layer as well as the luminescence properties of the quasi‐2D perovskite layer spin‐coated on top of it are able to be dramatically improved. As a result, the optimized Si‐based PeLEDs reach a maximum external quantum efficiency of 4.46% with a current efficiency of 19.7 cd A −1 , which is the highest value for Si‐based quasi‐2D PeLEDs to the authors’ knowledge.