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Nonfullerene electron acceptors (NFAs) improve the photoelectrical conversion efficiency of organic solar cells (OSCs), but they suffer from high synthetic cost and time‐consuming thermal annealing treatment. Nevertheless, low‐cost NFAs and simple device fabrication are still crucial issues to boosting the commercial application of OSCs. Herein, one kind of low‐cost pentacyclic NFAs based on benzothiadiazole and thiophene derivatives named L1‐EH and L1‐BO with different substitutions is successfully synthesized and characterized. The optimized OSCs based on PM6:L1‐BO (2‐butyloctyl side chain) display an outstanding power conversion efficiency of 13.15%. Moreover, OSC devices based on these acceptors operate in thermal annealing‐free conditions. Further studies manifest that the proper side chains in NFAs can induce more favorable face‐on molecule orientation, enhance carrier mobility, balance charge transport, and reduce recombination losses. This research demonstrates that these types of low‐cost NFAs are promising active layer candidates of high‐efficiency organic solar cells featuring simple device manufacture. [ABSTRACT FROM AUTHOR]

The effect of iron‐containing substances with different forms on the properties of carbon‐black filled natural rubber compound is discussed. The ionic iron substances (FeCl2, FeCl3, Fe(SA)3) have a detrimental effect on the rubber. Based on the oxidation induction temperature values, the relative deteriorating effects of ionic iron substances on the rubber are in the order: Fe(SA)3 > FeCl3 ≈ FeCl2. Not only are the metal ions (Fe2+, Fe3+) with adjacent stable oxidation states catalytically active in degrading rubber, but also the counterions have an influence on the effect of oxidation, particularly the stearic anion. Ionic iron materials can decrease the molecular weight, especially for the case of Fe(SA)3 as measured by gel permeation chromatography. Due to the degrading effect on the rubber molecules, Fe(SA)3 brings about a torque decrease in moving die rheometer and evident decrease of the Mooney viscosity at 100°C, which is different from the effects of Fe2O3 and 304L‐Fe. The insoluble iron substances behave more like hard fillers. Additionally, Fe(SA)3 remarkably alters the bound rubber content and the tensile properties after aging via two different process (scission and crosslinking). Overall, this work has a thorough comparison of effect of iron‐containing materials on rubber aging and provides useful inspiration to protect the rubber from deterioration by foreign reagents and regulating the rubber stability and degradation rate via introducing degradative metal ions. [ABSTRACT FROM AUTHOR]