Zhaobin Chen

Synthesis and photophysics of novel 8-hydroxyquinoline aluminum metal dye with hole transfer groups

A novel luminescent dye metal complex, (CZHQ)3Al, with 8-hydroxyquinoline aluminum and hole-transporting carbazole units was designed and synthesized. The (CZHQ)3Al optical properties were carefully investigated by UV-vis absorption and fluorescence spectra in diluent solution. The results showed that the luminescent quantum yield of (CZHQ)3Al was 0.62 in DMSO and it emitted red-light with the band gap of 2.89 eV estimated from the onset absorption. In addition, the light-emission of (CZHQ)3Al can be quenched by electron acceptor (dimethylterephalate), where the process followed the Stern-Volmer equation. However, the fluorescent intensities of (CZHQ)3Al were slowly increased with the addition of electron donor (N,N-dimethylaniline). Furthermore, the molecular interactions of (CZHQ)3Al with fullerene (C60) and carbon nanotubes (CNTs) were also respectively investigated, which indicated the metal dye can be used as new fluorescent probe.

Intramolecular charge transfer with 4-(N-phenylamino)benzoic acid. The N-phenyl amino conjugation effect

Abstract 4-( N -phenylamino)benzoic acid (PhABA) was synthesized and its fluorescence spectra were recorded. In aprotic polar solvents, PhABA emitted strongly Stokes-shifted single-banded fluorescence with practically the same wavelength as that of 4-( N , N -diphenylamino)benzoic acid (DPhABA), indicative of the ICT character of the emissive state. 4-( N -isopropylamino)benzoic acid (iPrABA) showed single band emission however, sluggish response to the solvent polarity. In alkanols dual fluorescence of PhABA and DPhABA was observed but with different dependencies on alkanol structures. We concluded that ICT occurring with PhABA was due to the N -phenyl/amino conjugation effect. The work could be of help in understanding speciality of anilino moiety as electron donor compared to aliphatic amino group.

Synthesis and photophysics of novel 8-hydroxyquinoline aluminum metal complex with 1,3,4-oxadiazole units.

A novel luminescent metal complex, (OXHQ)3Al, with 8-hydroxyquinoline aluminum and electron-transporting 1,3,4-oxadiazole unit was designed and synthesized. The photophysical processes were investigated by UV-vis absorption and fluorescence emission spectra in diluent solution. The results showed that the luminescence quantum yield of (OXHQ)3Al was 0.67 in DMSO and it emitted blue light with the band gap of 3.13 eV estimated from the onset absorption. In addition, the light-emitting of (OXHQ)3Al can be quenched by electron acceptor (dimethylterephalate), where the processes followed the Stern-Volmer equation. However, with the addition of electron donor (N,N-dimethylaniline) fluorescent intensity of (OXHQ)3Al was increased and emission peak was lightly blue-shift. Furthermore, the molecular interactions of (OXHQ)3Al with fullerene (C60) or carbon nanotubes (CNTs) were also carefully investigated.