Benzothiadiazole Research Articles

Multifunctional Narrow Band Gap Terpolymer-Enabled High-Performance Dopant-Free Perovskite and Additive-Free Organic Solar Cells with Long-Term Stability.

The optoelectronic devices endowing multifunctionality while utilizing a single low-cost material have always been challenging. For this purpose, we adopted a random ternary copolymerization strategy for designing two terpolymers, namely TP-0.8-EG and TP-0.8-TEG comprising a benzothiadiazole (BT)-benzo[1,2-b:4,5-b']dithiophene-diketopyrrolo[3,4-c]pyrrole (A1-π-D-π-A2) backbone. The figure of merits of the narrow band gap TP-0.8-EG terpolymer include deepened frontier energy levels, high hole mobility, better film formability, enriched multifunctionality, and passivation capability. Accordingly, the suitable electronic properties of TP-0.8-EG revealed that it can function as a dopant-free hole-transporting material in perovskite solar cells (PSCs) as well as the third component in organic solar cells (OSCs). Remarkably, TP-0.8-EG outperforms by exhibiting a higher power conversion efficiency (PCE) of 20.9% over TP-0.8-TEG (PCE of 18.3%) and BT-UF (PCE of 14.6%) in dopant-free PSCs. Interestingly, TP-0.8-EG fabricated along with PM6:Y7 displayed a high PCE of 16.52% in ternary OSCs. Also, TP-0.8-EG established good device storage stabilities (85 and 83% of their initial PCEs for 1200 and 500 h) in dopant-free PSC as well as OSC devices. Notably, the devices with TP-0.8-EG showed excellent thermal and moisture stabilities. To the best of our knowledge, A1-π-D-π-A2 terpolymer performing both in PSCs and OSCs with decent efficiencies and good device stabilities is a rare scenario.

Bioimaging and detecting endogenous and exogenous cyanide in foods, living cells and mice based on a turn-on mitochondria-targeted fluorescent probe

A novel fluorescent probe, with advanced features including “turn-on” fluorescence response, high sensitivity, good compatibility, and mitochondria-targeting function, has been synthesized based on structural design for detecting and visualizing cyanide in foods and biological systems. An electron-donating triphenylamine group (TPA) was employed as the fluorescent and an electron-accepting 4-methyl-N-methyl-pyridinium iodide (Py) moiety was used as a mitochondria-targeted localization unit, which formed intramolecular charge transfer (ICT) system. The “turn-on” fluorescence response of the probe (TPA-BTD-Py, TBP) toward cyanide is attributed two reasons, one is the insertion of an electron-deficient benzothiadiazole (BTD) group into the conjugated system between TPA and Py, and the other is the inhibition of ICT induced by the nucleophilic addition of CN–. Two active sites for reacting with CN− were involved in TBP molecule and high response sensitivity were observed in tetrahydrofuran solvent containing 3 % H2O. The response time could be reduced to 150 s, the linear range was 0.25–50 μM, and the limit of detection was 0.046 μM for CN− analysis. The TBP probe was successfully applied to the detection of cyanide in food samples prepared in aqueous solution, including the sprouting potato, bitter almond, cassava, and apple seeds. Furthermore, TBP exhibited low cytotoxicity, clear mitochondria-localizing capability in HeLa cells and excellent fluorescence imaging of exogenous and endogenous CN– in living PC12 cells. Moreover, exogenous CN– with intraperitoneal injection in nude mice could be well monitored visually by the “turn-on” fluorescence. Therefore, the strategy based on structural design provided good prospects for optimizing fluorescent probes.

π -Extended BTD derivatives: synthesis, photophysical properties, and applications in biological systemsimagingfor discriminating living and dead cells.

Benzothiadiazole (BTD) is one of the popular compounds for organic electronic devices, organic synthesis, and fluorescent probes. Here, benzothiadiazole derivatives were successfully synthesized by heck coupling reaction, which exhibited the the advantages of simplicity and efficiency, wild substrate csope, easily available substrates and high yield. The fluorescent probe BTDAr-PEG targeting lipid droplets was successfully prepared by the nucleophilic substitution reaction between the heck coupling reaction product 3h and Amino polyethylene glycol monomethyl ether (Mn=2000). BTDAr-PEG exhibited the advantages of high selectivity, good stability and pH resistance. The use of PEG as a substrate gave BTDAr-PEG good biocompatibility. It was worth mentioning that BTDAr-PEG could not only track LDs in cells under different physiological conditions, but also distinguish between living and dead cells in biological systems.

Unlocking the potential of 2,1,3-benzoxadiazole-based luminescent liquid crystals

ABSTRACT Here, we report the synthesis and characterisation of 2,1,3-benzoxadiazole-based (BOX) luminescent liquid crystals with a π-conjugated core and different elongated donor units connected by triple bonds. These molecules exhibited calamitic thermotropic mesomorphism with nematic and smectic phases and intense photoluminescence under UV–vis light excitation in solutions and films. In solution, the emission revealed a maximum in the yellow region (502 to 590 nm), similar to that of benzothiadiazoles (BTD) homologous, but with fluorescence quantum, it yields significantly higher (ΦPL = 0.30–54). The nature of donor unit substantially influenced the quantum yields and excited state lifetimes. Solvatochromism studies showed a dependence of the emission, quantum yield and lifetimes with the polarity of the solvent. This work demonstrates that 2,1,3-benzoxadiazole core derivatives have thermal and photophysical properties similar to BTDs but with superior quantum efficiency.

Organic nanomaterials from self-assembly of BODIPY-benzothiadiazole conjugate for PDT/PTT synergistic therapy

Near-infrared light-induced phototherapy including photothermal therapy (PTT) and photodynamic therapy (PDT) has emerged as a new noninvasive method for cancer treatment owing to the nature of high efficiency and spatiotemporal selectivity. In this study, a new boron-dipyrromethene (BODIPY) molecule (BDP-BT) with donor (D)-receptor (A)-donor (D) structure was designed and successfully synthesized by conjugation of benzothiadiazole (BT) with BODIPY structure. The polyethylene glycol chain (PEG) was modified onto the meso site of BODIPY to improve the hydrophilicity and biocompatibility of the compound. The amphiphilic BDP-BT was then self-assembled into nanoparticles (BDP-BT NPs) with red-shifted absorption and enhanced hydrophilicity. BDP-BT NPs can produce effective reactive oxygen species and local hyperthermia triggered by a single laser. The in vitro experiments revealed that BDP-BT NPs had good biocompatibility and remarkable photocytoxicity. The half maximal inhibitory concentration (IC[Formula: see text] of BDP-BT NPs was valued at 22.17 [Formula: see text]g/mL under 635 nm laser irradiation. Furthermore, BDP-BT NPs can efficiently generate reactive oxygen species (ROS) in the tumor cells under light irradiation. Thus, the as-prepared BDP-BT NPs could be used as promising agents for PDT and PTT synergistic cancer therapy.

A Direct Arylation Approach for the Preparation of Benzothiadiazole-Based Fluorophores for Application in Luminescent Solar ­Concentrators

AbstractA straightforward synthetic protocol featuring direct C–H arylations as key steps has been optimized to prepare two benzo-2,1,3-thiadiazole (BTD)-based organic fluorophores. Their light absorption and emission properties, as well as their affinity with poly(methyl methacrylate) as the chosen polymer matrix, were found to be suitable for application in luminescent solar concentrators. Solar-concentration devices were fabricated with both emitters, and their relevant optical and photovoltaic properties are presented.

Transcriptome analysis reveals resistance induced by Benzothiadiazole against soft rot in Chinese cabbage

Soft rot caused by Pectobacterium carotovorum (Pc) is a harmful disease in Brassica rapa, resulting in severe yield loss. Benzothiadiazole (BTH) can improve plant resistance to various pathogens by inducing systemic acquired resistance (SAR) pathway. In this study, susceptible wild type (WT) and resistant mutant sr in Chinese cabbage—both treated with BTH showed high resistance to Pc infection. Transcriptome analysis showed a series of differentially expressed genes (DEGs) involved in the regulation of leucine-rich repeat resistance (LRR) proteins, peroxidase (POD) accumulation, transcription regulatory factors, and other defense response functions. In particular, WRKY75 and PR4 genes were significantly induced by pathogens and BTH in WT and sr. BTH triggered the increase of endogenous SA. In addition, the enhanced activities of phenylalanine ammonia lyase (PAL) and POD promoted the accumulation of lignin after BTH treatment. We inferred that the lignin played significant roles in BTH-induced resistance of Chinese cabbage resistance to Pc. We present the potential molecular mechanism of BTH-induced resistance for soft rot resistance in Chinese cabbage, which provides a basis for further study of the resistance mechanism of Chinese cabbage to soft rot.

Non-fused Polymerized Small-Molecule Acceptors with a Benzothiadiazole Core for All-Polymer Solar Cells.

Polymerized small-molecule acceptors (PSMAs) have made significant progress as the application in all-polymer solar cells (all-PSCs). Most PSMAs are constructed by near-infrared fused-ring electron acceptors via Stille polymerization, such as Y-series acceptors. However, very limited non-fused electron acceptors with simplified synthetic complexity have been used in PSMAs. In this work, two non-fused PSMAs with a benzothiadiazole (BT) core are developed for application in all-PSCs. The S-O non-covalent interaction and the regioregularity have been introduced to improve the crystallinity and charge transport properties. As a result, a high-power conversion efficiency (PCE) of 11.42% with an enhanced photocurrent has been obtained in these regioregular PBTO-γ-based solar cells, representing the highest PCEs based on non-fused PSMAs. The encouraging results will intrigue more design of non-fused PSMAs toward high-performance all-PSCs.

2,1,3]-Benzothiadiazole-Spaced Co-Porphyrin-Based Covalent Organic Frameworks for O2 Reduction

Designing N-coordinated porous single-atom catalysts (SACs) for the oxygen reduction reaction (ORR) is a promising approach to achieve enhanced energy conversion due to maximized atom utilization and higher activity. Here, we report two Co(II)-porphyrin/ [2,1,3]-benzothiadiazole (BTD)-based covalent organic frameworks (COFs; Co@rhm-PorBTD and Co@sql-PorBTD), which are efficient SAC systems for O2 electrocatalysis (ORR). Experimental results demonstrate that these two COFs outperform the mass activity (at 0.85 V) of commercial Pt/C (20%) by 5.8 times (Co@rhm-PorBTD) and 1.3 times (Co@sql-PorBTD), respectively. The specific activities of Co@rhm-PorBTD and Co@sql-PorBTD were found to be 10 times and 2.5 times larger than that of Pt/C, respectively. These COFs also exhibit larger power density and recycling stability in Zn-air batteries compared with a Pt/C-based air cathode. A theoretical analysis demonstrates that the combination of Co-porphyrin with two different BTD ligands affords two crystalline porous electrocatalysts having different d-band center positions, which leads to reactivity differences toward alkaline ORR. The strategy, design, and electrochemical performance of these two COFs offer a pyrolysis-free bottom-up approach that avoids the creation of random atomic sites, significant metal aggregation, or unpredictable structural features.

Linear-Shaped Low-Bandgap Asymmetric Conjugated Donor Molecule for Fabrication of Bulk Heterojunction Small-Molecule Organic Solar Cells.

A linear-shaped small organic molecule (E)-4-(5-(3,5-dimethoxy-styryl)thiophen-2-yl)-7-(5″-hexyl-[2,2':5',2″-terthiophen]-5-yl)benzo[c][1,2,5]thiadiazole (MBTR) comprising a benzothiadiazole (BTD) acceptor linked with the terminal donors bithiophene and dimethoxy vinylbenzene through a π-bridge thiophene was synthesized and analyzed. The MBTR efficiently tuned the thermal, absorption, and emission characteristics to enhance the molecular packing and aggregation behaviors in the solid state. The obtained optical bandgap of 1.86 eV and low-lying highest occupied molecular orbital (HOMO) level of -5.42 eV efficiently lowered the energy losses in the fabricated devices, thereby achieving enhanced photovoltaic performances. The optimized MBTR:PC71BM (1:2.5 w/w%) fullerene-based devices showed a maximum power conversion efficiency (PCE) of 7.05%, with an open-circuit voltage (VOC) of 0.943 V, short-circuit current density (JSC) of 12.63 mA/cm2, and fill factor (FF) of 59.2%. With the addition of 3% 1,8-diiodooctane (DIO), the PCE improved to 8.76% with a high VOC of 1.02 V, JSC of 13.78 mA/cm2, and FF of 62.3%, which are associated with improved charge transport at the donor/acceptor interfaces owing to the fibrous active layer morphology and favorable phase separation. These results demonstrate that the introduction of suitable donor/acceptor groups in molecular design and device engineering is an effective approach to enhancing the photovoltaic performances of organic solar cells.

Soluble sugars, organic acids and energy metabolism involved in the wound healing of muskmelons elicited by benzothiadiazole

Benzothiadiazole (BTH) is an analogue of salicylic acid, which can reduce the disease severity in many harvested horticultural products via inducing resistance. In this study, muskmelons (cv. Perfect) were used as the materials to investigate BTH dipping on the sugars, organic acids and energy metabolism during healing. Results demonstrated that BTH increased fructose, glucose and sucrose contents at wounds of muskmelons in the early stage of healing. Further, BTH enhanced the contents of pyruvic acid, malic acid, fumaric acid, α-ketoglutaric acid and succinic acid, but decreased citric acid content. BTH also increased nicotinamide adenine dinucleotide (NAD) and its reduced form (NADH) contents. Moreover, BTH up-regulated ATP synthase subunit β and CmAAC expressions, but down-regulated CmAOX1D, CmUCP and CmPM-ATPase expressions, thereby maintaining the higher levels of adenosine triphosphate (ATP) and energy charge (EC). Taken together, BTH could promote the levels of soluble sugars, organic acids and energy at muskmelon wounds, which provide carbon skeletons and energy required for synthesis, transportation and cross linking of precursors of suberin and lignin, contributing to the formation of healing tissue.

Sensitive hydrazine detection and quantification with a fluorescent benzothiadiazole sensor: selective lipid droplets and in vivo imaging.

In this work, we describe the design, synthesis, characterization, photophysical evaluation, DFT calculations, and application of two novel fluorescent benzothiadiazole (BTD) sensors for hydrazine detection and quantification at the cellular and multicellular (in vivo) levels. The two probes were fully characterized, and their photophysical properties were evaluated. We tested the designed fluorogenic dye (named BTD-CHO) as a selective sensor for the rapid, sensitive, and selective detection of hydrazine. When treated with N2H4, the probe affords a new derivative named BTD-HZN, releasing water as the only byproduct. BTD-CHO exhibited a preference for lipid droplets (LDs) and accumulated inside these organelles. Hydrazine detection in LDs could be carried out by the in situ formation of BTD-HZN inside live cells. We efficiently visualized the lipids of a challenging cellular model, microalgae (Chlorella sorokiniana), using these sensors. In vivo experiments indicated rapid and efficient detection of the analyte using C. elegans and zebrafish (Danio rerio) as the multicellular models.

Tailoring the mechanical properties of benzothiadiazole-based semiconducting polymers through chalcogen atom substitution

The electrical, thermal, and mechanical properties of a series of benzothiadiazole (BT)-based conjugated polymers with different chalcogen atoms were investigated.

Electron-deficient moiety regulated structure: an efficient strategy for the design of a highly sensitive cyanide “turn-on” fluorescent probe

Developing fluorescent probes for the cyanide diagnosis is necessary as its extensive existence will seriously harm human health. Herein, the strategy for designing three novel probes came from our previously reported “turn-on” fluorescent probe, which was switched from a “turn-off” probe by inserting an electron-deficient benzothiadiazole (BTD) into a triphenylamine (TPA)-based dicyanovinyl (MT) compound with a phenyl group (Ph) as π-bridge (TPA-BTD-Ph-MT). To further investigate the effects of the electron-deficient group, BTD was firstly replaced by a stronger electron-deficient group of 2,3-diphenylquinoxaline (DPQ) to obtain TPA-DPQ-Ph-MT (P1). Based on P1 molecule, N-phenylcarbazole (PCZ), and thiophene (Th) were respectively used as a substitute to obtain PCZ-DPQ-Ph-MT (P2) and TPA-DPQ-Th-MT (P3) probes for investigating the effect of the electron donor and π-bridge on the fluorescent probe. P1 exhibited significant “turn-on” fluorescence response toward cyanide anion (CN−) with the best sensitivity and anti-interference performance. The sensing mechanism of P1 toward CN− was demonstrated and a good linearity was obtained in the wide concentration range of 0.025–40.0 μM with a low detection limit of 0.058 μM. Furthermore, P1 was successfully employed to determine CN– in food samples and image CN– in living cells and BALB/c mice, revealing its great practical potential for discriminative detection CN– in the fields of food and biological studies. Therefore, the strategy based on structure regulation provided good prospects for optimizing fluorescent probes.

Promising Integrated Management Strategy of Garlic Rust (Puccinia porri G. Wint.) with Improved Productivity Using Benzothiadiazole (BTH), Essential Oils and Fungicides

Promising Integrated Management Strategy of Garlic Rust (Puccinia porri G. Wint.) with Improved Productivity Using Benzothiadiazole (BTH), Essential Oils and Fungicides

Benzothiadiazole enhances ascorbate recycling and polyphenols accumulation in blueberry in a cultivar-dependent manner.

Benzothiadiazole (BTH) is a functional analogue of salicylic acid able to induce systemic acquired resistance in many horticultural crops. The aim of the work was to investigate how BTH may affect i) fruit quality, ii) ascorbic acid (AsA) oxidation and recycling metabolism and iii) phenolic compounds accumulation, during development and ripening of berries from the two selected cultivars. Blueberry (Vaccinium corymbosum L.) plants (cv 'Brigitta' and 'Duke') were treated with 0.118 mM BTH every two weeks during ripening, then all fruits of each plant were harvested and divided in four developmental stages. Results indicated that BTH had no marked effects on fruit quality parameters. During the first developmental stage, BTH negatively affected dry matter in both cv, while soluble solids and AsA content were affected in 'Duke'. In fully ripe berries, BTH reduced dry matter in 'Duke' and enhanced soluble solids content in 'Brigitta', while diminishing titratable acidity. AsA content was positively affected by BTH in 'Duke', but not in 'Brigitta'. The effect of BTH on the enzymes involved in AsA recycling was recorded in berries at the third (fruit more than half pigmented) and fourth developmental stages. After treatment, in both cv ascorbate peroxidase (APX) activity increased in fully ripe berries, while monodehydroascorbate reductase (MDHAR) activity was stimulated at the third ripening stage. Conversely, the activities of dehydroascorbate reductase (DHAR) and glutathione reductase (GR) were enhanced only in 'Brigitta' and in 'Duke', respectively. BTH stimulated total polyphenols, flavonoid and anthocyanin accumulation in 'Brigitta' and in 'Duke' at the third and fourth ripening stages. In fully ripe berries, BTH enhanced the accumulation of delphinidins, cyanidins, petunidins and peonidins in 'Brigitta', while in 'Duke' it increased all classes of anthocyanidins, including malvidin. On the contrary, the relative proportion of the individual anthocyanins was only slightly affected by BTH treatment, mainly regarding delphinidin and malvidin at the third and fourth stage of ripening of 'Duke' and 'Brigitta', respectively. These results show that preharvest BTH application can positively impact on fruit bioactive compounds levels, affecting AsA recycling and content and increasing polyphenols accumulation in fruit, but partly depending on cv and ripening stage.

Defense Inducers Mediated Mitigation of Bacterial Canker in Tomato through Alteration in Oxidative Stress Markers.

The bacterial canker disease of tomato caused by Clavibacter michiganensis subsp. michiganensis (Cmm) has been reported to adversely affect the tomato cultivation in the NE hilly regions of India. Defense inducers such as salicylic acid (SA), isonicotinic acid (INA), benzothiadiazole (BTH) and lysozyme were used as prophylactic and curative sprays at different concentrations to test their efficacy in inducing resistance in tomato plants against Cmm under protected conditions. The induced resistance was studied through the alteration in the activities of oxidative stress marker enzymes (PAL, PO, PPO, TPC and PR-2 protein), hydrogen peroxide formation in leaf tissues and lignin accumulation in stem tissues, as well as through the reduction in disease severity under glasshouse conditions. The results of the present study revealed that the enzymatic activity, hydrogen peroxide formation and lignin production were significantly higher in the BTH (500 ppm)-treated leaves than in those observed in the control. The lowest disease incidence was recorded when BTH was applied as a prophylactic spray (27.88%) in comparison to being applied as a curative spray (53.62%), thereby suggesting that a defense inducer, BTH, shows antibacterial activity against Cmm, reduces disease incidence severity and induces defense responses in the tomato plant.

Side substitution on benzothiadiazole-based hole transporting materials with a D–A–D molecular configuration for efficient perovskite solar cells

A series of benzothiadiazole-based Donor-Acceptor-Donor (D-A-D) typed hole-transporting materials (HTMs) are designed through introducing electron-withdrawing fluorine group and electron-donating alkoxy group into the core of benzothiadiazole (BT). The energy level alignment, electronic properties, absorption, and hole transport properties of these materials are explored comprehensively using First-principle calculations. As compared with the reference molecule BT, three other substituted molecules have lower HOMO energy levels and lower reorganization energy. Especially, two fluorine substituted hole-transporting materials BT-1F and BT-2F possess planar molecular configuration, suitable energy level, indicating that fluorine substitution is beneficial to the increase of open circuit voltage of device. Moreover, the hole transporting mobility, solubility and stability of all designed molecules are also estimated, which are important items to determine the cost and performance in real application of solar cells. Calculated results show that hole mobility of monofluorinated molecule BT-1F displays relatively higher hole mobility owing to efficient intermolecular interactions. Therefore, molecule BT-1F is likely to be highly efficient HTMs because of its excellent hole mobility and solubility. The present work demonstrates that fluorination engineering on core acceptors in D-A-D typed HTMs is an effective strategy to tune the photovoltaic performance of perovskite solar cells.

Benzothiadiazole induced changes in the transcriptome and regulation of banana fruit ripening and disease resistance

Benzothiadiazole (BTH) induces plant disease resistance and delays fruit ripening, but its possible mechanism of action remains unclear. Therefore this study investigated the effects of BTH on ripening and disease incidence in banana (Musa spp.) fruit. Our results showed that using BTH delayed ripening and maintained fruit firmness by inhibiting the enzymes involved in softening. BTH also delayed and reduced the occurrence of anthracnose caused by Colletotrichum musae during the ripening process. Transcriptome analysis identified 10,430 differentially expressed genes (DEGs) during the ripening process compared with freshly harvested fruit. Many DEGs were identified between the BTH and control group or prochloraz treatment, but only a few DEGs were found in the prochloraz treatment compared to the control group. A Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that the DEGs induced by the BTH treatment were primarily enriched in the synthesis of terpenoid quinones, plant-pathogen interaction, plant hormone signal transduction, phenylpropanoid biosynthesis, phenylalanine metabolism, peroxisome, and fatty acid biosynthesis among other pathways. BTH also induced the expression of many transcription factor (TF) families, including those in the WRKY, NAC, MYB and bHLH families, with the WRKY family being the most enriched. The WRKY TF interacts with many ripening- and secondary metabolism-related genes to regulate fruit ripening and disease resistance. Our results showed that, compared with the fungicide prochloraz, BTH alters the transcripts of the genes related to hormone signalling, secondary metabolism and resistance in the banana peel, and key TFs, thereby delaying fruit ripening, enhancing fruit resistance, and maintaining fruit quality.

Pre-Harvest Benzothiadiazole Spraying Promotes the Cumulation of Phenolic Compounds in Grapes.

Benzothiadiazole (BTH) is a commercial chemical elicitor that can induce an innate immune response in grapevines and improve the phenolic components and color quality of grapes and corresponding products. The literature on the influence of BTH on the accumulation and metabolism of phenols from grapes is extensive. However, many unknown bio-mechanisms involved have been poorly investigated, which opens a gateway for pioneering research that needs to be done in this field. To this purpose, this review aims to analyze and explore the gaps in current research so that subsequent studies may be geared towards them.