通过对PVK与4种新型D-π-A分子(分别简写为CKD,TKD,PKD,NKD)掺杂体系的吸收光谱、激发光谱和光致发光光谱的研究,分析了掺杂体系的光致发光特性和能量转移现象.制备了结构为ITO/PEDOT/PVK:D-π-Aω/Alq3/Al的电致发光器件,研究了掺杂体系的电致发光性能.研究结果表明,通过改变D-π-A分子中不同给电子能力的电子给体,可以调控其带隙,进而实现对D-π-A分子发光峰位的调节;给电子基团空间立构效应越高,其荧光量子效率越高.在掺杂体系的光致发光和电致发光中,PVK与D-π-A分子之间都发生了有效的能量转移,通过调节PVK与D-π-A分子的比例,可以调节掺杂体系的发光性能.当TKD在PVK中的掺杂质量分数为6%时,电致发光器件发光亮度为729.1cd/m^2时,发光效率达到1.75cd/A.
The energy transfer and the luminescent properties of PVK and four novel donor-π-acceptor(D-π- A) molecules( CKD, TKD, PKD, NKD) doped systems were investigated with the analysis of UV-Vis absorption spectra, photoluminescent excitation (PLE) spectra and photoluminescent (PL) spectra. The electrolumi-nescence(EL) properties of the blend system were studied via the characterization of the devices ITO/PE-DOT/PVK: D-π-A ω/Alq3/A1. The results demonstrate that by changing the donor moieties of D-π-A molecule, the band gap of D-π-A molecules can be adjusted. Meanwhile the fluorescence quantum efficiency va- ries significantly with the stereostructure of donor moieties of D-π-A molecules. Both the PL and EL spectra show that the energy transfer between PVK and D-π-A molecules occurs effectively. The emission performance of the blend system could be improved with changing the dopant ratio of PVK and D-π-A molecules. The pow- er efficiency of the device is up to 1.75 cd/A at 729. 1 cd/m^2, when the dopant mass fraction between PVK and TKD is 6. 0%.