Bottom Electrode Modification Enables Efficient and Bright Silicon‐Based Top‐Emission Perovskite Light‐Emitting Diodes

Abstract The integration of perovskites with mature silicon platform has emerged as a promising approach in the development of efficient on‐chip light sources and high‐brightness displays. However, the performance of Si‐based green perovskite light‐emitting diodes (PeLEDs) still falls significantly short compared to their red and near‐infrared counterparts. In this study, it is revealed that the high work function Au, widely employed in Si‐based top‐emission PeLEDs as the reflective bottom electrode, exhibits considerably lower reflectivity in the green spectrum than in the longer wavelengths. Consequently, Ag electrode is introduced to replace Au to enhance the green light reflectivity, and the ultrathin MoO 3 and self‐assembled monolayers (SAMs) are sequentially deposited for surface modification. These results indicate that the MoO 3 layer removes the energy barrier at Ag/polymer hole transport layer interface, enhancing the hole injection efficiency; while the SAMs firmly anchor onto the MoO 3 layer, effectively preventing interfacial defect formation. Benefited from this organic/inorganic dual‐layer modification strategy, Si‐based green PeLEDs with an impressive peak external quantum efficiency of 18.2% and a maximum brightness of 81931 cd m −2 are successfully fabricated, on par with those of the red and near‐infrared counterparts. This achievement marks an advancement in developing high‐performance Si‐based PeLEDs with full‐spectrum output.