| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1267730 | Organic Electronics | 2011 | 6 Pages |
A near-ultraviolet light emitting diode (LED) consisting of ZnO nanorods/MEH-PPV heterostructure and a layer of ZnS as the modification buffer layer is reported. Specially, the ZnO nanorods are grown on the ZnS hole-injecting buffer layer by hydrothermal method. Then the devices of ITO/ZnS/ZnO/ZnOnanorods/MEH-PPV/Al are prepared. Under forward bias, not only strong near-ultraviolet (N-UV) electroluminescence (EL) at 380 nm of ZnO band edge emission and weak defect-related emissions of ZnO nanorods at 410, 510 and 760 nm are observed, but also the exciton emission of MEH-PPV at 580 nm is detected. Along with increasing the thickness of ZnS film, the emission at 580 nm strengthens. Compared with the device ITO/ZnO/ZnOnanorods/MEH-PPV/Al we have reported in the past, the experimental results show that the suitable insertion of a ZnS thin layer can enhance the N-UV EL. Under the same voltage, the light intensity can be increased up to 10 times more than that of the device without a ZnS layer. Moreover, the turn-on voltage is reduced remarkably. The effect of ZnS as the hole-injecting buffer layer with different thickness on the EL of ZnO nanorods/MEH-PPV heterostructure is investigated.
Graphical abstractA near-ultraviolet light emitting diode (LED) consisting of ZnO nanorods/MEH-PPV heterostructure and a layer of ZnS as the modification buffer layer is reported. Under forward bias, the near-ultraviolet (N-UV) electroluminescence (EL) at 380 nm of ZnO band edge emission is observed. When the thickness of ZnS layer is suitable, the light intensity of the device with ZnS can be increased up to 10 times more than that of the device without a ZnS layer.Figure optionsDownload full-size imageDownload as PowerPoint slideResearch highlights► A layer of ZnS as the modification buffer layer is used to imporve the near-ultraviolet electroluminescence of ZnO nanorods/MEH-PPV heterostructure diode. ► Under forward bias, the near-ultraviolet electroluminescence at 380nm of ZnO band edge emission is observed. ► When the thickness of ZnS layer is suitable, the light intensity of the device with ZnS can be increased up to 10 times more than that of the device without a ZnS layer.
