| With excellent solubility and carrier injection/extraction ability, water/alcohol-solubleinterfacial materials are now widely utilized in organic optoelectronic devices. In presentresearch field, alkyl chains with polar groups such as amine, hydroxyl, phosphonate andzwitterionic groups are often used to realize the interfacial modification function. This kind ofmaterials is mainly based on polyelectrolytes and neutral conjugated polymers, and alsoincludes nonconjugated molecules and fullerene derivatives. In this thesis, we mainly focuson the synthesis and study of new water/alcohol-soluble interfacial materials based on thepyridine and phosphonate/phosphonic acid groups.This thesis firstly synthesized one novel water-soluble pyridinium salt Tz-3pyd with“triazine†as core and pyridinium as functional group. Due to its good solubility in water andstrong electron-withdrawing ability, Tz-3pyd can be easily processed from its water solutionand used as a cathode interlayer in inverted polymer solar cells (i-PSCs). The device withPECz-DTQx: PC71BM as active layer shows power conversion efficiency (PCE) of4.65%,which is higher than the device with ZnO interlayer and is almost two times as high as thebare Al device.To avoid adverse effects of moveable ions on the devices’ performance, we firstlysynthesized a series of small alcohol-soluble interfacial materials based on phosphonate andtriphenylamine groups, named3TPA-FEP, TPA-2FEP and TPA-3FEP. Then these materialswere applied to polymer light-emitting diodes (PLEDs) and polymer solar cells (PSCs) as thecathode interlayer. For the PLEDs with P-PPV as an emitting layer, the maximum currentefficiency of the devices using3TPA-FEP/Al and TPA-2FEP/Al as the cathode was11.5and14.3cd/A, respectively. While utilizing TPA-3FEP as the cathode interlayer, the maximumcurrent efficiency of18.0cd/A showed a29%increase compared to that of the traditionalBa/Al device. For the PSCs based on PCDTBT:PC71BM system, good PCE of6.89%and6.90%were achieved with TPA-2FEP and TPA-3FEP as the cathode interlayer, respectively.Especially, PCE of7.21%achieved by using3TPA-FEP as the cathode cathode interlayerwas among the best values for the PSCs based on the PCDTBT:PC71BMsystem. Based on the above phosphonate interfacial materials, we further developed a group ofalcohol-soluble interfacial materials based on the phosphoric acid group, named3TPA-FPOH,2TPA-2FPOH and TPA-3FPOH. Then we did a systematic study on the thermal,photophysical and electrochemical properties of these materials. It was found that thephosphoric acid group could also have deep influence on the related properties of thematerials as well as the backbone structure. |
