•Some PAs were synthesized and showed excellent electrochromic stability.•The Energy gap (Eg) can be tuned by the structure of acid, as well as amine.•The influence of the film’s morphology on the coloring efficiency was discussed.•The EIS of the PAs were measured and showed they have good electric conductivity.Two series of novel aromatic polyamides (PAs) were synthesized via polymer condensation reaction based on N,N'-bis(4-aminophenyl)-N,N'-di-1-naphthalenyl-[1,1′-biphenhyl]-4,4′-diamine, N,N'-bis(4-aminophenyl)-N,N'-diphenyl-4,4′-biphenyl diamine and different binary acids compounds. The structures of the monomers and polymers were characterized by Fourier transform infrared spectroscopy (FT-IR), hydrogen nuclear magnetic resonance (1H NMR). The electrochromic properties of the PAs were investigated by using the ultra-visible-near infrared (UV–Vis–NIR) spectrophotometer and electrochemical workstation. The color of the polymer films changed from light yellowish to brown, then atroceruleous or brilliant blue with an increasing potential. Then we discussed the relationship of morphology on coloration efficiency. The electrochemical impedance spectroscopy (EIS) also has been used to characterize the internal resistances of PAs film electrodes.Electronic absorption spectra of PAPBD-P thin film and its 3D spectra upon the increasing voltage.Download high-res image (304KB)Download full-size image

Different concentrations of bis-β-diketonate complex Eu2(BTP)3(Phen)2 (BTP = 1,3-bis(4,4,4-trifluoro-1,3-dioxobutyl)-phenyl and Phen = 1,10-phenanthroline) were doped into the poly(methylmethacrylate) (PMMA), forming a series of red Eu/PMMA luminescent nanofibers, via electrospinning technology. Various characterization techniques were employed to reveal the effect of Eu2(BTP)3(Phen)2 on the morphology, thermal stability, and luminescence of composite nanofibers. FT-IR spectra show the Eu2(BTP)3(Phen)2 complex was successfully doped into PMMA. The luminescent spectra of the composite nanofibers show strong characteristic emission of Eu3+ ions. Simultaneously, in comparison with the precursor complex Eu2(BTP)3(Phen)2, the Eu/PMMA nanofibers has a great improvement in thermal stability. Furthermore, the Judd-Ofelt theory and simulative constructions of the complex are employed to explain the effect of the dispersion of Eu2(BTP)3(Phen)2 and the interactions between the Eu2(BTP)3(Phen)2 complex and neighboring chain segments of PMMA.

A new bis(β-diketonate), 1,3-bis(4,4,4-trifluoro-1,3-dioxobutyl)phenyl (BTP), which contains a trifluorinated alkyl group, has been prepared for the synthesis of two series of dinuclear lanthanide complexes with the general formula Ln2(BTP)3L2 [Ln3+ = Eu3+, L = DME(1), bpy(2), and phen(3); Ln3+ = Sm3+, L = DME(4), bpy(5), and phen(6); DME = ethylene glycol dimethyl ether, bpy = 2,2′-bipyridine, phen = 1,10-phenanthroline]. The crystal structure of the free ligand has been determined and shows a twisted arrangement of the two binding sites around the 1,3-phenylene spacer. X-ray crystallographic analysis reveals that complexes 1, 2, 4, and 5 are triple-stranded dinuclear structures formed by three bis-bidentate ligands with two lanthanide ions. The room-temperature photoluminescence (PL) spectra of complexes 1–6 show that this bis-β-diketonate can effectively sensitize rare earths (Sm3+ and Eu3+) and produce characteristic emissions of the corresponding Eu3+ and Sm3+ ions. In addition, two bidentate nitrogen ancillary ligands, 2,2′-bipyridine (bpy) and 1,10-phenanthroline (phen), have been employed to enhance the luminescence quantum yields and lifetimes of both series of Eu3+ and Sm3+ complexes.