纳米MEH-PPV阵列的光致发光  

Photoluminescence of Nano-MEH-PPV Arrays

作　　者：孔凡[1] 黄高山[1] 杨益民[1] 杨昌正[2] 吴兴龙[1] 鲍希茂[1] 袁仁宽[1] 

机构地区：[1]南京大学物理系,江苏南京210093 [2]南京大学化学化工学院,江苏南京210093

出　　处：《发光学报》2005年第6期785-788,共4页Chinese Journal of Luminescence

基　　金：国家自然科学基金资助项目(59832100)

摘　　要：以多孔氧化铝为模板,将可溶性发光聚合物聚(2-甲氧基-5-(2′-乙基己氧基)-1,4-对苯乙炔)(MEH-PPV)镶嵌在纳米孔中,制备出高发光效率的纳米发光聚合物阵列,其光学特性与MEH-PPV薄膜显著不同。纳米孔内的MEH-PPV分子链形成链束,链束中的分子链数目依赖于制备纳米MEH-PPV阵列所用溶液的浓度。相对于稀溶液,在由浓溶液制备的纳米MEH-PPV阵列中,MEH-PPV链束的分子链数目较多,链间作用使MEH-PPV的能带展宽,能隙减小,因而浓溶液获得的纳米MEH-PPV阵列的光致发光峰红移。热处理纳米MEH-PPV阵列的PL谱表明,纳米孔内的聚合物分子链的弛豫运动受到限制。Poly （p-phenylene vinylene） （PPV） and its derivatives have been investigated in electronics and photonics because of their excellent electronic and optical properties. It has been demonstrated that nanostructured PPVs are endowed with specialties for applications in new fields, such as wave-guiding and all-optical switching. Using porous anodic alumina with an ordered nanopore array as a template, the luminescent polymer MEH-PPV has been embedded into the nanopores as the template was immersed in MEH-PPV solution for 48 hours, then the template was taken out and washed with THF to drive out MEH-PPV chains on the surface of the anodic alumina template and then nano-MEH-PPV array was formed after the solvent volatilizes. It was demonstrated by analyzing of photoluminescence （PL） spectra that the optical properties of the nano-MEH- PPV array are obviously different from that of MEH-PPV film. It is also represented experimentally that the conformation of MEH-PPV in the nanopores of the anodic alumina is chain bunch. The number of MEH-PPV chains in the bunch depends on the concentration of the polymer solution for preparing the nano-MEH-PPV array. As the anodic alumina template is immersed in MEH-PPV solution with higher concentration, more MEH-PPV chains move into the nanopores to form the bunch. Due to interchain interaction, the energy bands of the MEH-PPV bunch are widened to decrease its energy gap, and then the PL peak of the nano-MEH-PPV is red-shifted. The more the polymer chains of the bunch, the wider the energy bands of the bunch and the larger the red-shift of the PL peak of the polymer in the nanopores. So the optical properties of the nano-MEH- PPV array can be controlled by adjusting the concentration of the polymer solution for preparing the nano- MEH-PPV array. It is demonstrated by the PL spectra of the nano-MEH-PPV array annealed at different temperatures that the relaxation of MEH-PPV in the nanopores is limited and the nano-MEH-PPV shows highly thermal stabilities.

关 键 词：PPV及其衍生物 光致发光 纳米材料 

分 类 号：O482.31[理学—固体物理]