基于三苯胺和芴的D-A型高分子信息存储材料的合成及性能

Synthesis and WORM Memory Effect of a Donor-Acceptor Polymer with an Integrated Fluorene and Triphenylamine Backbone

设计和合成了一种高度可溶的基于三苯胺和芴的D-A型高分子信息存储材料PFTD(Poly{[4,4′-(4.4′-(9H-fluorene-9,9-diyl)bis(4,1-phenylene))bis(oxy)diphthalonitrile][triphe-nylamine][9,9-dioctyl-9H-fluorene]})。随着溶剂极性的增加,荧光强度逐渐减弱,荧光发射谱带变宽且发生红移,最大发射峰分别位于426nm(甲苯),432nm(四氢呋喃),442nm(苯腈),445nm(N,N-二甲基甲酰胺)。PFTD在THF稀溶液中的绝对荧光量子效率为47.8%,由于固体时强的荧光淬灭效应,旋涂在石英玻璃片上的薄膜绝对荧光量子效率仅为5.5%。通过电化学实验估算得到的HOMO、LUMO、能隙、离子化势和电子亲和势分别为-5.43、-2.62、2.81、5.69、2.88eV。由该聚合物制备的薄膜器件(器件结构:ITO/PFTD/Al)表现出典型的一次写入、多次读出(WORM)型记忆特性,电流开关比大于104,开启电压为-1.5V。

A novel highly soluble donor-acceptor polymer, poly{[-4,4＇-（4.4＇-（9H-fluorene 9,9-diyl）bis （4,1- phenylene） ） bis （oxy） diphthalonitrile] [-triphenylamine] [9,9-dioctyl-9H-fluorene] } （ PFTD）, was designed and synthesized through the Suzuki coupling reaction. The fluorescence intensity of PFTD decreased as the solvent polarity increased. Its emission band was observed to get broader and red shifted （3,=426 nm （toluene）, 432 nm （THF）, 442 nm（PhCN） and 445 nm （DMF））. The absolute fluorescence quantum yield of PFTD changed from 47.8% for a dilute THF solution to 5.5%o for a thin film due to the existence of a strong fluorescence quenching effect in the solid state. The HOMO, LUMO, band gap, IP and EA values experimentally estimated from the onset of the redox potentials were - 5. 43, - 2. 62, 2.81, 5. 69, 2. 88 eV, respectively. The PFTD film was attached to aluminum and indium-tin oxide contacts to fabricate a memory device with typical bistable electrical switching, non-volatile write-once read-many-times （WORM） memory performance, a turn-on voltage of approximately -1.5 V and an ON/ OFF ratio of more than 104.