Conjugated organic molecules based on core benzothiophene (BT) and benzothiophene S,S-dioxide (BTO), substituted with triphenylamines at positions 3,5,6 and 2,4,7, were designed via Suzuki couplings. Optoelectronic properties were studied, and theoretical calculations were carried out to understand the structured absorbance spectra of the various compounds. All compounds exhibited bright emission within the visible region, ranging from blue for BT to yellow-orange for BTO. Organic light-emitting diode (OLED) devices were fabricated through an air-processed spin-coating method where all layers, except the top cathode, were solution-processed. Device luminance exceeded 1000 cd/m2 using 2,4,7-triphenylaminebenzothiophene S,S-dioxide, which in turn was successfully translated to a large-area module slot-die coated on a plastic substrate.

B(C 6 F 5 ) 3 is a versatile Lewis acid with utility in a range of applications including olefin polymerization, metal-free catalysis, batteries, and organic electronics. This perspective highlights applications of B(C 6 F 5 ) 3 and presents alternatives.

Interlayers in organic solar cells (OSCs) are crucial for efficient charge carrier transport and extraction. Recent research has introduced cathode interlayer (CIL) materials, which are soluble in polar, amphiphilic, and non-polar solvents. However, studies on how these solvents affect device performance, particularly stability under various conditions, remain limited. In this work, we investigate the effects of the chemical structure of a recently synthesized perylene diimide (PDI) CIL material, F-PDIN-EH, and its eco-friendly polar (methanol), amphiphilic (1-butanol), and non-polar (heptane) processing solvents, on device performance, compared to PDINO, a widely studied PDI-based CIL material. This is one of the first investigations into the effect of non-polar CIL processing solvents on device stability. OSC devices with F-PDIN-EH yield comparable efficiency to PDINO-based devices but are consistently less stable, irrespective of the solvent. Notably, the heptane-processed F-PIN-EH-based devices exhibit the lowest stability. We investigated the degradation mechanisms in the device and the interfaces through an in-depth study using TPV, TPC, extracted charge carrier density, and light intensity dependence of Jsc and Voc. Further studies are conducted using absorption spectroscopy, FTIR, and mobility measurements to ascertain the source of degradation. The loss in performance over time, especially in the heptane-processed F-PIN-EH-based devices, is mainly due to increased surface recombination and imbalanced charge mobility. This study provides valuable insights into the dependency of device performance on the chemical structure and processing solvents of CIL materials. It also highlights challenges for sustainable, greener OSCs.

Modern photodynamic therapy (PDT) demands next-generation photosensitizers (PSs) that overcome heavy-atom dependency and enhance efficacy beyond traditional, highly oxygen-dependent type II mechanisms. We introduce herein TCI-NH, as a thiochromenocarbazole imide derivative designed for type I photodynamic action. Upon light activation, TCI-NH efficiently favors superoxide (O2•-) and PS-centered radical formation instead of singlet oxygen (1O2) generation. Its high luminescence efficiency and selective localization in both the endoplasmic reticulum and mitochondria enable precise, image-guided PDT. Notably, interactions with biomolecules, such as serum albumin or DNA, enhance TCI-NH's emission by up to 40-fold and amplify radical generation by up to 5-fold. With negligible dark toxicity, this results in ∼120 nM photocytotoxicity along with an impressive phototherapeutic index exceeding 200. Real-time live-cell imaging revealed rapid, light-triggered cytotoxicity characterized by apoptotic body formation and extensive cellular damage. With its small size, heavy-atom-free structure, exceptional, organelle specificity, and therapeutic efficacy, TCI-NH sets a new benchmark for anticancer type I PDT.

With an increased demand for lithium ion (Li-ion) battery technologies, and the small number of lithium mines around the globe, there has been a heightened desire to develop new materials capable of extracting lithium from aqueous sources such as the ocean. To do so in an economically viable way, the materials must be highly selective toward the extraction of Li-ions so as not to necessitate the further purification from competing metal ions such as magnesium, sodium, or calcium. To address this, herein we report on three new conjugated imide compounds functionalized with the crown ether benzo-9-crown-3. The three new compounds Phth-CE, F-Phth-CE, and NMI-CE were synthesized via atom-economical condensation reactions between an amino functionalized benzo-9-crown-3 with commodity aryl imide building blocks. These three new compounds serve to develop an understanding of Li-ion capture via the benzo-9-crown-3 moieties scaffolded onto stable aromatic ring systems. The nodal plane between the aryl imide and the phenyl ring of benzo-9-crown-3 isolates the crown ether allowing for unhindered Li-ion capture and release. Subtle derivatization of the aryl imide showcases structural versatility to include a fluoride amenable to nucleophilic aromatic substitution and/or to act as a diagnostic handle and naphthalene unit extending optical absorption to longer wavelengths. Each new compound exhibits the formation of Li-ion sandwich complexes as determined by 7Li NMR spectroscopy, and near identical Li-ion extraction efficiencies, distribution coefficients, and selectivity under acidic conditions in neat and mixed-metal ion solutions as determined by triple quadrupole inductively coupled plasma mass spectrometry analysis.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

The development of modern optoelectronic devices increases the need for lightweight and flexible transparent conductors. It is thus essential to develop new eco-friendly materials that can be easily processed for the fabrication of such devices. For this purpose, the synthesis of self-doped, highly conducting, transmissive, and water-processable polythiophene derivatives was performed via the direct heteroarylation polymerization method and a protection/deprotection strategy. Stable conductivities up to 1000 S cm(-1) have been obtained. Champion materials (P1 and P7) were scaled and processed via the roll-to-roll compatible slot-die coating method to demonstrate their large area applicability. The best coated films exhibited optical transmittance greater than 79% at 550 nm with sheet resistances of 116 Omega square(-1). These values are comparable to indium-tin oxide on plastic and thus present a viable alternative to metal oxide-based electrodes.

The direct comparison of two push-pull based dimers prepared in only three steps from commercially and affordable building blocks is reported herein. Built around similar absorbing units, two ethylene glycol sigma-connectors of different lengths were used to investigate, and rationalize, their impact on the optical, self-assembly and therefore photovoltaic properties. With significant differences from the charge transport, morphology and therefore power conversion efficiencies, results gathered in this study emphasized the potential of such simple yet efficient strategy to fine tune the processability of an active compound. Two push-pull based dimers, built around similar absorbing units and linked by two ethylene glycol sigma-connectors of different lengths are reported herein. Effects on the optical, self-assembly and therefore photovoltaic properties are rationalized, highlighting significant differences from the charge transport, morphology of the active layers and therefore power conversion efficiencies.image

A new fluorinated N-annulated perylene diimide molecule for use as a cathode interlayer in organic solar cells. Fluorination increases solubility and allows for processing from a range of green solvents, including heptane for the first time.

We report the synthesis and characterization of two new molecules based on the N-annulated perylene diimide (PDIN-H) dye, modified with an octyl sulfide or octyl sulfone group. The octyl sulfone group increases electron affinity of the PDI core for higher sensitivity to amine detection in both solution and film, which was validated by using a flexible electronic sensing platform towards n-butylamine detection.

Herein, we perform a stability assessment of two conjugated polymers that are conventionally used as electron donor polymers in the active layer of organic photovoltaic (OPV). More specifically, the impact of thermal annealing, a post-treatment commonly applied in the OPV community, is evaluated in terms of device performance and stability. The two polymers are PTB7-Th and QX1, and they are respectively blended with a non-fullerene electron acceptor, herein a derivative of N-annulated perylene diimide, that is, tPDI(2)N-EH. These blends are targeted for their relatively high power conversion efficiency in outdoor conditions, but also for their potential as efficient active layer in low-intensity (indoor) conditions-while these blends have been reported, no study on the impact of thermal annealing on their stability has been performed yet. The performance stability of these devices, tracked via the open circuit voltage, the short-circuit current, the fill factor, and the power conversion efficiency metrics, were evaluated each day for 2 weeks and correlated to an evaluation of the microstructure of the active layer, evaluated using atomic force microscopy and UV-visible absorbance spectroscopy. Finally, transistors were prepared using only the two electron donor polymers, PTB7-Th and QX1, to assess if some correlations could be made between the behaviour of the OPV devices and that of the electronic charge mobilities. Results contribute to identify which molecular structures and which post-treatments are ideal to promote the stability of the active layers in the context of OPV devices.

Utilizing a streamlined five-step synthesis process, we have successfully produced a diverse set of adjustable benzo[4,5]thieno-S,S-dioxide-[3,2-b]benzofurans-based compounds via Michael's addition-elimination reaction, Suzuki-Miyaura coupling, and intramolecular oxidative C-H/C-H coupling, in 70-90% yields. The synthetic strategy employed demonstrates that the compounds can be modified on either side by introducing various types of groups at positions 2 and 3, with the possibility of extending the aromatic portion in place of benzofuran. Thus, these compounds exhibit a distinctive dual-state emission, showcasing very good quantum yields up to 63% in the solid state and 83% in solution. Additionally, these compounds were integrated into ambient conditions and solution-processed, nondoped OLEDs, demonstrating promising results with a luminance of 850 cd/m2 and a turn-on voltage of 3.50 V.

Thermally induced degradation of organic photovoltaic devices hinders the commercialization of this emerging PV technology. Thus, a precise understanding of the origin of thermal device instability, as well as identifying strategies to circumvent degradation is of utmost importance. Here, it investigates thermally‐induced degradation of state‐of‐the‐art PBDB‐T‐2F (PM6):BTP (Y6) bulk heterojunction solar cells at different temperatures and reveal changes of their optical properties, photophysics, and morphology. The open‐circuit voltage and fill factor of thermally degraded devices are limited by dissociation and charge collection efficiency differences, while the short‐circuit current density is only slightly affected. Energy‐resolved electrochemical impedance spectroscopy measurements reveal that thermally degraded samples exhibit a higher energy barrier for the charge‐transfer state to charge‐separated state conversion. Furthermore, the field dependence of charge generation, recombination, and extraction are studied by time‐delayed collection field and transient photocurrent and photovoltage experiments, indicating significant bimolecular recombination limits device performance. Finally, coupled optical‐electrical device simulations are conducted to fit the devices’ current‐voltage characteristics, enabling us to find useful correlations between optical and electrical properties of the active layers and device performance parameters.

Chemical sensors based on blends of organic semiconductors with molecular sensitizers show exceptional sensitivity to amines by leveraging a charge transfer reaction.

Large area inverted type organic solar cells based upon a dye modified tin oxide electron transport layer are reported.

To achieve high-performance indoor organic photovoltaics (OPVs), it is important to match the photoactive layer optical absorption with the light-source emission. This can be accomplished by developing organic photoactive materials that can efficiently absorb visible light and thus minimize energy losses. While indoor OPVs have achieved efficiencies above 33% under low light intensities, the power output is limited by low open circuit voltages (VOC), often well below 1 V. In this study, we present a series of visible-light absorbing (energy gap >1.90 eV) non-fullerene acceptors (NFAs) based on perylene diimide dimers, which have been systematically modified with side chains of varying polarity and steric bulk (trimethyl benzyl, ethyl adamantane, trialkoxyl phenyl, and oligo ethylene glycol). Our results show that the incorporation of sterically bulky side chains such as ethyl adamantane and trimethyl benzyl, blended with the common widegap polymer PTQ10, provides photoactive layers with absorption greater than 2.0 eV, and consequently, V-OC(s) higher than 1.2 V are achieved under AM 1.5 G illumination. Importantly, we found that the NFA with ethyl adamantane based side chains (tPDI(2)N-ethyl adamantane, compound 4) exhibited the best performance, with minimized energy loss. As a result, devices using PTQ10:tPDI(2)N-ethyl adamantane photoactive layers demonstrated excellent indoor efficiencies of over 16% and 18 mu W cm(-2) power output under a 2700 K LED lamp at 300 lux, and showed better repeatability compared to other systems. The PTQ10:tPDI(2)N-ethyl adamantane based devices maintained a high VOC (>1.0 V) across a wide range of indoor lighting conditions, including 2700 K and 6500 K LED lamps. Overall, this work provides a sidechain engineering method to create NFAs for efficient indoor OPV devices.