Electronic Characteristics of Perylene Diimide Anion Radical and Dianion Films by Quantitative Doping

Due to their unique physicochemical properties,the anion radical and dianion of perylene diimide derivatives(PDIs)recently attracted significant attention for organic semiconductors.However,the impact of packing structure and the radical content for carrier transport in the solid state still need to be determined.Bringing the electron-withdrawing groups is an effective strategy for enablingπ−πstacking distance.Here,bay-tetrachloro-substituted PDI(B-4Cl-PDI)anion radical and dianion films were fabricated quantitatively doped with N_(2)H_(4)·H_(2)O.The radical contents were quantitatively calculated by absorption spectra in different doping ratios.The X-ray powder diffraction patterns showed that the anion radical presented a crystalline structure,and dianion aggregates exhibited an amorphous structure.With precise manipulation of the radical content,the anion radical aggregates and dianion aggregates showed the maximum electrical conductivity value of 0.024 and 0.0018 S/cm,respectively.The experiment results show that doping level and aggregate structure play a crucial role in electronic transport properties.

Cationic conjugated polymers as signal reporter for label-free assay based on targets-mediated aggregation of perylene diimide quencher

Herein, we reported a new label-free and fluorescence turn-on biosensor based on cationic conjugated poly（9,9-bis（6＇-N,N,N-trimethylammonium）hexyl）fluorine phenylene）（PFP） and perylene diimide derivatives（PDI）. Cationic PFP, single-stranded nucleic acid and PDI were used as signal reporter, probe and fluorescence quencher, respectively. In the presence of nucleic acids, they form complexes with PFP and PDI through strong electrostatic attraction interactions, resulting in PDI aggregating on nucleic acids and fluorescence of PFP being quenched. When nucleic acids are hydrolyzed by enzymes or their conformation is changed via recognizing targets, the effective aggregation of PDI is disrupted and the quenching ability is decreased. Thus the fluorescence of PFP recovers significantly. By taking advantage of the mechanism, we construct a new biosensor for endonuclease and small molecules detection. Here, S1 nuclease and bisphenol A are used as model systems. The detection limit of the SI nuclease and BPA are1.0×10^-6U/mL and 0.05 ng/mL, respectively. Our method is sensitive, cost-effective and simple, and provides a new platform for bioanalysis.

Synthesis,characterization,photophysical and electrochemical properties of oxygen bridged twisted heptatomic biphenyl substituted perylene diimides

The perylene diimide derivatives（s-THBPDI and d-THBPDI） bearing oxygen bridged twisty heptatomic biphenyl in the bay positions of the perylene core through acetylene bond were designed and synthesized.The photophysical properties of the functionalized dyes were investigated in solution and solid state by UV-vis and photoluminescence（PL） spectra.Their UV-vis and PL spectrum both exhibited the different concentration-dependent behaviors due to the difference of chemical structure.Moreover,cyclic voltammetry results indicated that the introduction of oxygen bridged twisted heptatomic biphenyl could decrease the LUMO energy level of the perylene diimide effectively and made it promising material in photoelectric devices.