Light-Emission Enhancement in a Flexible and Size-Controllable ZnO Nanowire/Organic Light-Emitting Diode Array by the Piezotronic Effect

Enhancing the light emission of LED arrays by the piezotronic effect of ZnO NWs has recently attracted wide attention for the visual mapping of pressure. Here, to overcome deficiencies of I ZnO LEDs, such as uncontrollable emission and poor emission efficiency, we designed a flexible, patterned ZnO/organic light-emitting device by combining the advantages of organic light-emitting materials and the piezoelectric effect of ZnO nanowires (NWs). The spatial resolution of the device can be tuned by the pattern size of the ZnO NW array. In addition, the light-emission character is solely determined by the organic light-emitting layer. The light-emission performance of the organic device is enhanced by the piezotronic transistors of the ZnO NW array through the modification of the energy band and reducing the Schottky barrier at the interface of the electrode and the semiconductor. By combining the advantages of the organic material and the piezotronic effect of ZnO NWs, this device shows potential for many applications, such as mechanosensation electronics.