基于电荷转移过程的PAN-C60共聚物薄膜的时间分辨荧光研究

利用吸收光谱和皮秒时间分辨荧光研究PAN－C60星状共聚物的电荷转移过程。PAN－C60共聚物的吸收和荧光光谱结果显示共聚物中存在着电荷转移过程。时间分辨荧光结果表明PAN的荧光衰减遵循双指数衰减规律（一快过程160ps和一慢过程1500ps)，快衰减过程主要来源于聚合物中主链间相互作用产生的空间间接极化子对的影响，慢变过程主要来源于单重态激子的辐射跃迁弛豫。在共聚物中，C60分子的存在除导致PAN激发态寿命缩短外，还影响聚合物链间的相互作用，C60分子对PAN荧光猝 灭作用主要通过慢变过程影响的，而对PAN的空间极化子对的影响主要与其快衰减过程有关。

The Charge Transfer Process of PAN-C60 Copolymer Films by Time-resolved Fluorescence Spectra

The charge transfer (CT) process in PAN-C 60 copolymer films was studied by absorption and picosecond time-resolved photoluminescence (TRPL) spectra.The CT process can be confirmed from the appearing of new absorption bands and fluorescence quenching of pure PAN in the copolymer films.The TRPL result revealed that excitation state relaxation obeyed biexponential decay process,which were 160 ps and 1 500 ps for the fast and slow decay process,respectively.The fast decay process results from the interaction of chains in the polymer,and a slow decay process comes from the singlet exciton recombination.In the copolymer,the singlet exciton state lifetime of PAN becomes shorter due to CT process between PAN and C 60,which lead to PL quenching of PAN.Additionally,C 60 molecules also affect the interchain interaction of PAN by its spacial shape,which closely relates with the fast decay process.