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Blade‐coating which is compatible with roll‐to‐roll (R2R) fabrication has been considered a promising technology for the large‐scale production of organic solar cells (OSCs). Despite the rapid increase in power conversion efficiency (PCE) of the devices, most processing solvents are still halogenated, which is a key issue that needs to be addressed urgently in commercialized manufacturing. In this work, targeted strategies are explored for the preparation of efficient OSCs via combining the nonhalogenated solvent toluene (TL) with blade‐coating. Based on the in situ UV–vis absorption, grazing‐incidence wide‐angle X‐ray scattering, and device performance measurements, the subtle relationship between processing solvents, film morphology, and properties is successfully established. The PM6:BTP‐eC9 blend film prepared by this strategy demonstrates higher crystallinity and smaller phase separation morphology, resulting in an outstanding PCE of 16.58% with low energy loss and high fill factor, which is higher than the CF‐based device (15.08%). Finally, the 1.00 cm2 device exhibits a high PCE of 14.82%, which is one of the highest values for OSCs prepared by blade‐coating based on TL solvent. This specific strategy combines blade‐coating with nonhalogenated solvent processing shows outstanding synergy in optimization of morphology, demonstrating excellent potential for the preparation of highly efficient large area OSCs. [ABSTRACT FROM AUTHOR]

All current highest efficiency perovskite solar cells (PSCs) use highly toxic, halogenated solvents, such as chlorobenzene (CB) or toluene (TLN), in an antisolvent step or as solvent for the hole transporter material (HTM). A more environmentally friendly antisolvent is highly desirable for decreasing chronic health risk. Here, the efficacy of anisole (ANS), as a greener antisolvent for highest efficiency PSCs, is investigated. The fabrication inside and outside of the glovebox showing high power conversion efficiencies of 19.9% and 15.5%, respectively. Importantly, a fully nonhalogenated solvent system is demonstrated where ANS is used as both the antisolvent and the solvent for the HTM. With this, state-of-the-art efficiencies close to 20.5%, the highest to date without using toxic CB or TLN, are reached. Through scanning electron microscopy, UV-vis, photoluminescence, and X-ray diffraction, it is shown that ANS results in similar mixed-ion perovskite films under glovebox atmosphere as CB and TLN. This underlines that ANS is indeed a viable green solvent system for PSCs and should urgently be adopted by labs and companies to avoid systematic health risks for researchers and employees. [ABSTRACT FROM AUTHOR]

Abstract: All current highest efficiency perovskite solar cells (PSCs) use highly toxic, halogenated solvents, such as chlorobenzene (CB) or toluene (TLN), in an antisolvent step or as solvent for the hole transporter material (HTM). A more environmentally friendly antisolvent is highly desirable for decreasing chronic health risk. Here, the efficacy of anisole (ANS), as a greener antisolvent for highest efficiency PSCs, is investigated. The fabrication inside and outside of the glovebox showing high power conversion efficiencies of 19.9% and 15.5%, respectively. Importantly, a fully nonhalogenated solvent system is demonstrated where ANS is used as both the antisolvent and the solvent for the HTM. With this, state‐of‐the‐art efficiencies close to 20.5%, the highest to date without using toxic CB or TLN, are reached. Through scanning electron microscopy, UV–vis, photoluminescence, and X‐ray diffraction, it is shown that ANS results in similar mixed‐ion perovskite films under glovebox atmosphere as CB and TLN. This underlines that ANS is indeed a viable green solvent system for PSCs and should urgently be adopted by labs and companies to avoid systematic health risks for researchers and employees. [ABSTRACT FROM AUTHOR]

A wide-bandgap polymer, (poly[(2,6-(4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)-benzo[1,2- b:4,5- b′]dithiophene))- alt-(2,5-(methyl thiophene carboxylate))]) (3MT-Th), is synthesized to obtain a complementary broad range absorption when harmonized with 3,9-bis(2-methylene-(3-(1,1-dicyanomethylene)-indanone))-5,5,11,11-tetrakis(4-hexylphenyl)-dithieno[2,3- d:2′,3′- d′]- s-indaceno[1,2- b:5,6- b′]dithiophene (ITIC). The synthesized regiorandom 3MT-Th polymer shows good solubility in nonhalogenated solvents. A film of 3MT-Th:ITIC can be employed for forming an active layer in a polymer solar cell (PSC), with the blend solution containing toluene with 0.25% diphenylether as a nonhalogenated additive. The corresponding PSC devices display a power conversion efficiency of 9.73%. Moreover, the 3MT-Th-based PSCs exhibit excellent shelf-life time of over 1000 h and are operationally stable under continuous light illumination. Therefore, methyl thiophene-3-carboxylate in 3MT-Th is a promising new accepting unit for constructing p-type polymers used for high-performance nonfullerene-type PSCs. [ABSTRACT FROM AUTHOR]

Dispersive liquid-liquid microextraction (DLLME) combined with gas chromatography and mass spectrometry (GC-MS) was applied to the determination of five organophosphorous pesticides (OPPs) in water samples. The analytes included in this study were prophos, diazinon, chlorpyrifos methyl, fenchlorphos, and chlorpyrifos. The use of nonhalogenated solvents (cyclohexane, heptane, and octane) as extraction solvents was investigated using acetone, acetonitrile, or methanol, as dispersion solvents. The combination of less polar dispersion solvents (1-propanol and 2-propanol) and nonhalogenated extraction solvents was also studied in dispersive liquid-liquid microextraction for the first time. Several experimental conditions were tested (nature and volume of extraction solvents, nature and volume of dispersion solvents, salting-out effect) and the corresponding enrichment factors and recoveries were evaluated. The best microextraction condition was obtained using 50 μL of cyclohexane and 0.3 mL of 1-propanol. The detection and quantification limits were in the low ppt range, with values between 3.3-8.0 ng/L and 11.0-26.6 ng/L, respectively. Relative standard deviations were between 6.6 and 13.1% for a fortification level of 500 ng/L. At the same fortification level, the relative recoveries (RR) of Alvito's dam water, Judeu's river water, and well water samples were in the range of 50.3-97.1%. [ABSTRACT FROM AUTHOR]

Significant progress has been made in nonfullerene small molecule acceptors (NF‐SMAs) that leads to a consistent increase of power conversion efficiency (PCE) of nonfullerene organic solar cells (NF‐OSCs). To achieve better compatibility with high‐performance NF‐SMAs, the direction of molecular design for donor polymers is toward wide bandgap (WBG), tailored properties, and preferentially ecofriendly processability for device fabrication. Here, a weak acceptor unit, methyl 2,5‐dibromo‐4‐fluorothiophene‐3‐carboxylate (FE‐T), is synthesized and copolymerized with benzo[1,2‐b:4,5‐b′]dithiophene (BDT) to afford a series of nonhalogenated solvent processable WBG polymers P1‐P3 with a distinct side chain on FE‐T. The incorporation of FE‐T leads to polymers with a deep highest occupied molecular orbital (HOMO) level of −5.60−5.70 eV, a complementary absorption to NF‐SMAs, and a planar molecular conformation. When combined with the narrow bandgap acceptor ITIC‐Th, the solar cell based on P1 with the shortest methyl chain on FE‐T achieves a PCE of 11.39% with a large Voc of 1.01 V and a Jsc of 17.89 mA cm−2. Moreover, a PCE of 12.11% is attained for ternary cells based on WBG P1, narrow bandgap PTB7‐Th, and acceptor IEICO‐4F. These results demonstrate that the new FE‐T is a highly promising acceptor unit to construct WBG polymers for efficient NF‐OSCs. [ABSTRACT FROM AUTHOR]

In article number 1700566, Min Ju Cho, Dong Hoon Choi, and co‐workers report a new conjugated widebandgap donor polymer, 3MT‐Th, harmonized with an ITIC acceptor to enable the production of a polymer solar cell (PSC) with high efficiency of 9.73% under eco‐friendly conditions using a non‐halogenated solvent. This PSC also exhibits excellent shelf‐life stability in air and good operational stability under continuous light illumination. [ABSTRACT FROM AUTHOR]