Volatile solid additives are an effective strategy for optimizing morphology and improving the power conversion efficiencies (PCEs) of organic solar cells (OSCs). Much research has been conducted to understand the role of solid additives in active layer morphology. However, it is crucial to delve deeper and understand how solid additives affect the entire morphology evolution process, from the solution state to the film state and the thermal annealing stage, which remains unclear. Herein, the use of a highly crystalline solid additive, phenoxathiin (Ph), in D18‐Cl:N3‐based OSCs and study its impact on morphology formation and photovoltaic performance is presented. Owing to its good miscibility with the acceptor N3, Ph additive can not only extend the time for the active layer to form from the solution state to the film state, but also provide sufficient time for acceptor aggregation. After thermal annealing, Ph solid additive volatilizes better aligned the N3 molecules and formed a favorable hybrid morphology. Consequently, the D18‐Cl:N3–based OSC exhibited an outstanding PCE of 18.47%, with an enhanced short‐circuit current of 27.50 mA cm−2 and a fill factor of 77.82%. This research is spurring the development of high‐performance OSCs using solid additives that allow fine control during morphology development.
The side-chain engineering of A-DA'D-A-type nonfullerene acceptors (NFAs), well-known as Y6 series, is an efficient approach for retaining the physical properties of Y6-series but allowing manipulation of the solubility, crystallization,...
Modifying the end-capping groups in nonfullerene acceptors
(NFAs)
is an effective strategy for modulating their properties and that
of the entire NFAs. This study reports the synthesis of a novel γ-ester-functionalized
IC end-capping group (IC-γe) and its incorporation into the
benzothiadiazole-fused central core, yielding isomer-free IC-γe
end-capped NFAs, such as Y-IC-γe, Y-FIC-γe, and Y-ClIC-γe.
The resultant NFAs exhibited similar absorption profiles but upshifted
the lowest unoccupied molecular orbital energy level compared with
those of the ester-free analogues, such as Y6 and Y7. Without thermal
annealing, an excellent power conversion efficiency (PCE) of 16.4%
is realized in the annealing-free OSC based on Y-FIC-γe with
the PM6 donor polymer, which outperforms the OSCs based on Y-IC-γe
and Y-ClIC-γe. In addition, the OSCs based on asymmetric Y-FIC-γe
and Y-ClIC-γe have higher thermal stability with more than 83%
PCE retention at an elevated temperature after 456 h than the symmetric
Y-IC-γe case. In this study, we not only establish the structure–property
relationship regarding the ester functionality and symmetricity tuning
on the NFAs but also diagnose the reasons for the best-performing
Y-FIC-γe-based OSCs, providing useful information for a novel
high-performing NFA design strategy.
Introduction: Understanding marketing strategies and price competition among manufacturers is essential to manage health care expenditures, particularly those related to blockbuster drugs. Objectives: To assess marketing and pricing strategies of blockbuster drugs in South Korea. Methods: Baseline information on manufacturers who were granted marketing approval for choline alfoscerate in various forms was retrieved. Accumulation of manufacturers in the market was also identified, and manufacturers were categorized into first movers and latecomers based on their marketing time. Then, an event history analysis and a regression analysis were applied to estimate the duration of marketing and their price competition. Results: Currently, 109, 83, and 26 manufacturers produce choline alfoscerate in capsule, tablet, or syrup form, respectively, indicating that many manufacturers have marketed generics and the majority of the generics are categorized as latecomers. The size of the manufacturer was a significant factor in marketing new medicines, while the variable was not related to the marketing of modified drugs. Furthermore, price competition in the market was rare and only a few major firms initiated price competition. Conclusion: The Korean market appears to be an example of perfect competition when we focus on the number of manufacturers. However, the market is near-monopolistic when examining the price of generic drugs. While product competition between different forms of drugs is effective in lowering price, product competition within the same form of a drug does not exist in the market.
A simultaneous further increase in the power conversion efficiency (PCE) and device stability of organic solar cells (OSCs) over the current levels needs to be overcome for their commercial viability. Herein, a bay‐area benzamide‐functionalized perylene diimide‐based electron transport layer, namely H75 is developed, to obtain the aforementioned characteristics. The advantages of H75‐employed OSCs include a notable PCE up to 18.26% and outstanding device stabilities under conditions of varying severity (>95% PCE retention after 1500 h upon long‐term aging and exceptional T80 lifetimes (the time required to reach 80% of initial performance) of over 1000 h in light‐soaking, 500 h in thermal stress at 85 °C, 72 h in 85% high relative humidity, and 100 h in atmospheric‐air conditions without encapsulation in conventional architecture). The excellent performance of H75‐employed OSC can be attributed to its various beneficial features derived from the bay‐area benzamide functionalities (e.g., excellent film‐forming ability, suitable energy level, reduced aggregation, and intrinsic high structural stability). The findings of this work provide further insights into the molecular design of electron transport layers for realizing more efficient and stable OSCs.
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