Synthesis, structures and properties of two donor-acceptor acridone-based compounds

Two donor-acceptor acridone-based compounds, namely, 2-{10-[4-(diphenylamino)phenyl]acridin-9-ylidene}malononitrile (TPA-AD-DCN), C34H22N4, and 2-{10-[4-(9H-carbazol-9-yl)phenyl]acridin-9-ylidene}malononitrile (CzPh-AD-DCN), C34H20N4, have been synthesized in high yield and their structures determined. TPA-AD-DCN and CzPh-AD-DCN crystallized in the centrosymmetric space groups P-1 and P21/c, respectively. Both molecules adopt a `butterfly-like' configuration of the common part of the structure and differences occur within the substituents on the acridine N atom. A Hirshfeld surface analysis showed that the H...H and C...H/H...C contacts constitute a high percentage of the intermolecular interactions. The optical and electrochemical properties, as well as theoretical calculations, of TPA-AD-DCN and CzPh-AD-DCN support the structural characterization of these materials. As crystallization-induced emission materials, TPA-AD-DCN and CzPh-AD-DCN are anticipated to be of potential use in the construction of promising optoelectronic materials.

Synthesis and photocatalytic properties of visible-light-responsive, three-dimensional, flower-like La–TiO2/g-C3N4 heterojunction composites

We prepared a new three-dimensional, flower-like La–TiO₂/g-C₃N₄ (LaTiCN) heterojunction photocatalyst using a solvothermal method. Analysis and characterization were performed by conducting scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform-infrared spectroscopy, ultraviolet-visible spectrophotometry, and nitrogen adsorption and desorption. The prepared g-C₃N₄ nanosheets could reach 100 nm in size and covered the TiO₂ surface. A tightly bound interface formed between the g-C₃N₄ and TiO₂, speeding up the effective transfer of photo-induced electrons. In addition, the incorporation of La³⁺ reduced the electron–hole recombination efficiency. Consequently, the prepared La–TiO₂/g-C₃N₄ composite material exhibited better visible-light catalytic activity than pure TiO₂.

A new visible-light-responsive, three-dimensional, flower-like La–TiO₂/g-C₃N₄ heterojunction photocatalyst was prepared by a solvothermal method.

Interaction of pyridine π-bridge-based poly(methacrylate) dyes for the fabrication of dye-sensitized solar cells with the influence of different strength phenothiazine, fluorene and anthracene sensitizers as donor units with new anchoring mode

A simple and low-cost approach for the synthesis of three novel propeller-shaped (D₂)–π–A type organic polymer dyes has been developed; a new acceptor and π-bridge (PYN) were used to tune the photoelectric properties: DFT studies.

Unveiling the photophysical and morphological properties of an acidochromic thiophene flanked dipyrrolopyrazine-based chromophore for optoelectronic application

A series of dipyrrolopyrazine (DPP) based chromophores featuring thiophene and varied donor (N,N-dimethylamine, NH₂, OMe) and acceptor (CF₃, CN, NO₂) appendages have been synthesized. The structures and properties of the chromophores were investigated by absorption spectroscopy, electrochemistry, differential scanning calorimetry, and thermogravimetric analysis. X-ray crystallographic analysis indicates a planar geometry for the molecule 7g. Surface morphological studies reveal the formation of microrods and nanorods. The acidochromic behavior of the chromophore which shows a prominent red-shift in the absorption spectra owing to the protonation of the pyrazine segment provides a valuable opportunity to assess the sensory response. Acid dependent spectral changes could be successfully applied to detect pH in biological fluids and acid impurities in solvents.

A series of dipyrrolopyrazine (DPP) based chromophores featuring thiophene and varied donor (N,N-dimethylamine, NH₂, OMe) and acceptor (CF₃, CN, NO₂) appendages have been synthesized.