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In this work, the synthesis of BODIPY-phenyl-triazole labelled coumarins (BPhTCs) using a two-step approach is described. The influence of the BODIPY appending on the photophysical, electrochemical and thermal properties of the phenyl-triazole-coumarin precursors (PhTCs) was investigated. Band gap energies were measured by absorption spectroscopy (2.20 ± 0.02 eV in the solid and 2.35 ± 0.01 eV in solution) and cyclic voltammetry (2.10 ± 0.05 eV). The results are supported by DFT calculations confirming the presence of lowest LUMO levels that facilitate the electron injection and stabilize the electron transport. Their charge-transport parameters were measured in Organic Field-Effect Transistor (OFET) devices. BPhTCs showed an ambipolar transistor behavior with good n-type charge mobilities (10 -2 cm 2 V -1 s -1 ) allowing these derivatives to be employed as promising semiconducting crystalline and fluorescent materials with good thermal and air stability up to 250 °C., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Itzia Irene Padilla-Martinez reports financial support was provided by National Council on Science and Technology (CONACYT now CONAHCYT, National Council on Humanities, Science and Technology), Mexico. Norberto Farfan reports financial support was provided by National Council on Science and Technology, Mexico. Jose Emilio de la Cerda-Pedro reports financial support was provided by National Council on Science and Technology, Mexico. Oscar Javier Hernandez-Ortiz reports financial support was provided by National Council on Science and Technology, Mexico. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors. Published by Elsevier Ltd.)

A π-conjugated polymer (PBQT) containing bis-(2-ethylhexyloxy)-benzo [1,2-b'] bithiophene (BDT) units alternated with a quinoline-vinylene trimer was obtained by the Stille reaction. The chemical structure of the polymer was verified by nuclear magnetic resonance ( 1 H NMR), Fourier transform infrared (FT-IR), and mass spectroscopy (MALDI-TOF). The intrinsic photophysical properties of the solution were evaluated by absorption and (static and dynamic) fluorescence. The polymer PBQT exhibits photochromism with a change in absorption from blue (449 nm) to burgundy (545 nm) and a change in fluorescence emission from green (513 nm) to orange (605 nm) due to conformational photoisomerization from the trans to the cis isomer, which was supported by theoretical calculations DFT and TD-DFT. This optical response can be used in optical sensors, security elements, or optical switches. Furthermore, the polymer forms spin-coated films with absorption properties that cover the entire visible range, with a maximum near the solar emission maximum. The frontier molecular orbitals, HOMO and LUMO, were calculated by cyclic voltammetry, and values of -5.29 eV and -3.69, respectively, and a bandgap of 1.6 eV were obtained, making this material a semiconductor with a good energetic match. These properties could suggest its use in photovoltaic applications.

Perovskite solar cells (PSCs) are an evolving photovoltaic field with the potential to disrupt the established silicon solar cell market. However, the presence of many transport barriers and defect trap states at the interfaces and grain boundaries has negative effects on PSCs; it decreases their efficiency and stability. The purpose of this work was to investigate the effects on efficiency and stability achieved by quaternary theophylline additives in MAPbI 3 PSCs with the structure FTO/TiO 2 /perovskite/spiro-OMeTAD/Ag. The X-ray photoelectron spectroscopy (XPS) and theoretical calculation strategies were applied to study the additive's interaction in the layer. The tetrafluoroborinated additive results in an increase in device current density ( J SC ) (23.99 mA cm -1 ), fill factor (FF) (65.7%), and open-circuit voltage ( V OC ) (0.95 V), leading to significant improvement of the power conversion efficiency (PCE) to 15.04% compared to control devices (13.6%). Notably, films exposed to controlled humidity of 30% using the tetrafluoroborinated additive maintained their stability for more than 600 hours (h), while the control films were stable for less than 240 hours (h)., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

3-(4-Formylphenyl)-triazole-coumarin hybrid chromophores (FPhTCs) were synthesized in good yields, using a click chemistry protocol, and were also structurally characterized. Their photophysical, electrochemical and thermal properties were measured demonstrating that FPhTCs are luminescent in the blue-violet region of the electromagnetic spectrum, both in solution and the solid state. They showed an electrochemical band-gap values of 2.79 ± 0.08 eV, resistivity values between 10 4 and 10 5 Ω cm and are thermally stable up to 225 °C, properties that promise FPhTCs as good candidates for optoelectronic or imaging applications. Their solution and solid state photoluminescent properties are discussed and supported by theoretical calculations., Competing Interests: The authors declare no competing financial interest., (This journal is © The Royal Society of Chemistry.)

In this work, two oligophenyleneimines type pentamers with terminal aldehydes, designated as DAFCHO (4,4'-((((((2,5-bis(octyloxy)-1,4-phenylene)bis(methanylylidene))bis(azanyl ylidene))bis(9H-fluorene-7,2-diyl))bis(azanylylidene))bis(methanylylidene))bis(2,5-bis(octyloxy) benzaldehyde)) and FDACHO (4,4'-((((((2,5-bis(octyloxy)-1,4-phenylene)bis(methanylylidene))bis (azanylylidene))bis(4,1-phenylene))bis(azanylylidene))bis(methanylylidene))bis(2,5-bis(octyloxy) benzaldehyde)) were synthesized by mechanochemistry method using 2,5-bis(octyloxy) terephtal aldehyde and 2,7-diaminofluorene or 1,4-phenylenediamine. All compounds were spectroscopically characterized using ¹H and 13 C-NMR, FT-IR and mass spectrometry MALDITOF. The optical properties of the compounds were analyzed by UV-vis spectroscopy using different solvents. We observed that DAFCHO and FDACHO exhibit interesting photochromic properties when they are dissolved in chloroform and exposed to sunlight for 3, 5 and 10 min. The value of the energy band gap was calculated from the absorption spectra without irradiation E gap(optical) . It was 2.50 eV for DAFCHO in chloroform solution, and it decreased to 2.34 eV when it is in films. For FDACHO, it was 2.41 eV in solution and 2.27 eV in film. HOMO (Highest Occupied Molecular Orbital), LUMO (Lowest Unoccupied Molecular Orbital) and E gap(electrochemical) values were obtained by electrochemical studies. The results indicate that the compounds can be considered as organic semiconductors since their values are 2.35 eV for DAFCHO and 2.06 eV for FDACHO. The structural and electronic properties of the compounds were corroborated with a DFT (Density Functional Theory) study.

In 2-methyl-1,4,5-triphenyl-1H-imidazole, C(22)H(18)N(2), the three substituent phenyl groups are not delocalized with the imidazole moiety; the dihedral angles these phenyl groups form with the imidazole ring are in the range 25.90 (5)-63.49 (6) degrees.