聚苯胺/ZnO纳米线薄膜材料作为发光层的柔性光电器件 及其发光机理

综合氧化锌纳米线(ZnO NWs)的光学活性与聚苯胺(PANI)的空穴传输特性,设计并制备了一种聚合物/ZnO纳米线电致发光材料,并对其发光特性进行了研究。通过高分子络合软模板法,将有序的单晶ZnO NWs均匀生长在覆有铟锡氧化物(ITO)涂层的柔性聚乙烯对苯二甲酸乙二醇酯(PET)衬底上并嵌入PANI薄膜,获得了电致发光薄膜材料和有机/无机异质结实验器件ITO/(ZnO NWs-PANI)。有机/无机异质结器件电致发光可调,在相对低的开启电压下呈现室温蓝紫外发光,并且ZnO NWs表面覆盖PANI增加了蓝紫外发光的强度和稳定性;而无PANI的ZnO NWs阵列具有450 nm处的缺陷发射峰,这可能是电子从扩展态锌间隙Zn_i到价带的跃迁引起的。这些结果表明,基于PANI/ZnO纳米线的复合材料在柔性光电器件方面的应用极具潜力。

Photo-and Electro-luminescence of PANI/ZnO Nanowire Film for Light-emitting Layer of Flexible Optoelectronic Devices

With the combination of optical activity of ZnO nanowires and the hole-transporting characteristics of polyaniline(PANI),a flexible light-emitting diode based on PANI /ZnO nanowire film was designed and prepared,and luminescence properties were discussed.By our simple polymer-assisted growth method,the ordered single-crystalline ZnO nanowires were uniformly distributed on flexible polyethylene terephthalate(PET)-based indium-tin-oxide-coated substrates.The array of ZnO nanowires grown on PET substrate was successfully embedded in a polyaniline thin film,through which a PANI/ZnO nanowire film and a hybrid device of organic-inorganic hetero-junction of ITO/(ZnO nanowires-PANI) were obtained.The photo-and electroluminescence results show that the hybrid device of organic-inorganic hetero-junction is of tunable electroluminescence and emits ultraviolet at relatively low turn-on voltage;surface capping with PANI on ZnO nanowires enhances ultraviolet emission and reduces defect-related emission at 450 nm of bare ZnO nanowire array,which is attributed to electron transitions from the extended state Zni to the valance band.The results also indicate that PANI/ZnO nanowire film has a great potential for application in flexible optoelectronic devices.