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The micro-morphology and molecular stacking play a key role in determining the charge transport process and nonradiative energy loss, thus impacting the performances of organic solar cells (OSCs). To address this issue, a non-fullerene acceptor PhC6-IC-F with alkylbenzene side-chain, possessing optimized molecular stacking, complementary absorption spectra and forming a cascade energy level alignment in the PM6:BTP-eC9 blend, is introduced as guest acceptor to improve efficiency of ternary OSCs. The bulky phenyl in the side-chain can regulate crystallinity and optimizing phase separation between receptors in ternary blend films, resulting in the optimal phase separations in the ternary films. As a result, high efficiencies of 18.33% as photovoltaic layer are obtained for PhC6-IC-F-based ternary devices with excellent fill factor (FF) of 78.92%. Impressively, the ternary system produces a significantly improved open circuit voltage (Voc) of 0.857 V compared with the binary device, contributing to the reduced density of trap states and suppressed non-radiative recombination result in lower energy loss. This work demonstrates an effective approach for adjusting the aggregation, molecular packing and fine phase separation morphology to increase Voc and FF, paving the way toward high-efficiency OSCs. [ABSTRACT FROM AUTHOR]

The construction of C-N bonds is of great importance in the fields of biology, medicine, chemistry and materials science. Here, the replacement of organic base from pyridine to piperidine in the Knoevenagel condensation process unexpectedly yields a series of novel organic molecules containing C-N bonds. Interestingly, the synthesis method does not require any external transition-metals catalysis, and photo-/electro-catalysis. Additionally, when the new compound 1b is added as a third component to a well-known binary system of PM6:Y6, the efficiency of the organic solar cell is significantly improved, resulting in an outstanding efficiency of 18.0%, which is one of the highest values reported to date for PM6:Y6-based ternary organic solar cells. [ABSTRACT FROM AUTHOR]

Molybdenum disulfide (MoS) nanosheets are a promising lubricant additive for enhanced engine efficiency in cars. However, high-cost production methods and poor dispersion have limited their application in industry. In this study, the ball milling process is demonstrated as a low-cost and high-efficient method for fabrication of oil-dispersible MoS nanosheet, and the ball milling parameters are optimized. Moreover, the lubrication effectiveness of ball-milled MoS nanosheet was also evaluated. Results indicated that well-dispersed MoS nanosheets with a size of 250 nm can be manufactured with optimized surfactants of zinc dialkyldithiphosphates (ZDDP) and polyisobutylene succinimide (PIBS) after being ball milled for 36 h. Tribological results revealed that a friction coefficient of white oil with 0.25% MoS nanosheets reached 0.075, much lower than that of lubricant without nanosheets (0.16). The wear scar radius of 0.015% MoS nanosheets was similar with that of Hertz contact, and the wear scar radius reduction reached 20% compared with that of 1% ZDDP. In addition, EDS and XPS results indicated the formation of a MoS and FeS tribofilm on the wear surface. [ABSTRACT FROM AUTHOR]