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A bromine‐substituted [2‐(9H‐Carbazol‐9‐yl) ethyl] phosphonic acid, 1Br‐2PACz, is designed as hole‐selective self‐assembled monolayers (SAMs), contributing to an outstanding power conversion efficiency (PCE) of 19.35% for binary bulk‐heterojunction (BHJ) based organic solar cells (OSCs). As compared to the previous high‐performance 2Br‐2PACz SAMs, 1Br‐2PACz molecules can effectively reduce the interaction of the SAM with the BTP‐eC9 nonfullerene acceptors with a decreased binding energy, resulting in the suppressed vertical self‐aggregation of BTP‐eC9 small molecules as the bottom side of PM6:BTP‐eC9 BHJ during the solidification process. There is decreased energetic disorder within photoactive layer together with more efficient charge transfer and suppressed non‐radiative recombination. Furthermore, five additional binary BHJ systems are applied in 1Br‐2PACz SAM‐based OSCs, exhibiting continuously superior performance as compared to the reference cells with conventional PEDOT:PSS hole transport layer. This work underscores the potential of advancing OSCs by fine‐tuning SAMs through halogenation strategies to improve active layer morphology and overall device performance. [ABSTRACT FROM AUTHOR]

The yield stress of mud is one key to analyze the initiation and deposition of debris flow. Taking Chengdu clay as the experimental material, slurries with different solid volume concentrations were prepared. Using the blade rotor system of mcr301 rheometer and the continuous shear experimental method, the dynamic change process of shear stress of slurries with different solid volume concentrations was obtained with the shear rate increasing and decreasing continuously. According to the experimental results, the static and dynamic yield stress of Chengdu clay slurry is determined, and the influence of solid volume concentration on the yield stress is analyzed. The following conclusions are obtained: Chengdu clay slurry is a non-Newtonian fluid with yield stress. In the process of accelerated shear, for Chengdu clay slurry with solid volume concentration exceeding 35%, the shear rate is in the range of 0.01–1 s−1, and the shear stress increases rapidly to the maximum. When the shear rate exceeds 1 s−1, the shear stress decreases rapidly and finally tends to be stable. The shear rate appears stress overshoot near 1s−1. However, in the process of increasing shear rate, for Chengdu clay slurry with solid volume concentration of no more than 35%, the shear stress increases rapidly in the range of shear rate of 0.01–0.1 s−1, and the shear rate exceeds 0.1 s−1. The shear rate has little effect on the shear stress, and the stress overshoot disappears. In the process of deceleration shear, for all solid volume concentrations in the semi logarithmic coordinate system, the mud shear stress decreases steadily with the decrease of shear rate. The static and dynamic yield stress of slurry increases exponentially with particle concentration.

The ternary strategy proves effective for breakthroughs in organic photovoltaics (OPVs). Elevating three photovoltaic parameters synergistically, especially the proportion‐insensitive third component, is crucial for efficient ternary devices. This work introduces a molecular design strategy by comprehensively analyzing asymmetric end groups, side‐chain engineering, and halogenation to explore the outstanding optoelectronic properties of the proportion‐insensitive third component in efficient ternary systems. Three asymmetric non‐fullerene acceptors (BTP‐SA1, BTP‐SA2, and BTP‐SA3) are synthesized based on the Y6 framework and incorporated as the third component into the D18:Y6 binary system. BTP‐SA3, featuring asymmetric terminal (difluoro‐indone and dichloride‐cyanoindone terminal), with branched alkyl side chains, exhibited high open‐circuit voltage (VOC), balanced crystallinity and compatibility, achieving synergistic enhancements in VOC (0.862 V), short circuit‐current density (JSC, 27.52 mA cm−2), fill fact (FF, 81.01%), and power convert efficiency (PCE, 19.19%). Device based on D18/Y6:BTP‐SA3 (layer‐by‐layer processed) reached a high efficiency of 19.36%, demonstrating a high tolerance for BTP‐SA3 (10–50%). This work provides novel insights into optimizing OPVs performances in multi‐component systems and designing components with enhanced tolerance. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) have recently gained recognition as highly effective photocatalysts for solar energy conversion, in which manipulation of the electronic structures of photocatalysts is crucial for optimizing their photocatalytic performances. In this study, four benzothiadiazole and its derivative-based COFs (HIAM-0007 to HIAM-0010) were rationally designed and synthesized, which show remarkable differences toward photocatalytic oxidative amine coupling and hydrogen peroxide generation. The benzothiadiazole-based COF exhibits efficient oxidative amine coupling with a yield of up to 99%, while the naphthothiadiazole-based COF shows the highest rate of 796 μmol g−1 h−1 for photocatalytic hydrogen peroxide generation from air and water without additional reagents. This work underscores the variability in the activity of individual COFs across different photocatalytic reaction systems, demonstrating that the best performance is a combination of the electronic structures of COFs and the surrounding reaction environment. [ABSTRACT FROM AUTHOR]

The cathode interface layers (CILs) play a crucial role in enhancing the performance of organic solar cells (OSCs). However, challenges arise due to the high work function of CIL and inadequate contact with the active layer, leading to high interface trap recombination and poor charge extraction. In this study, a novel approach is proposed to improve charge injection and extraction in CILs by incorporating polyphenols, trihydroxybenzoic acid (TBA). Focusing on the CIL PDINN, its work function is successfully reduced from 4.14 eV to 3.80 eV and obtained charge collection efficiency of 91.23% through TBA regulation. These enhancements can be ascribed to improved contact between the active layer and the CILs, and enhanced the formation of a fine fiber phase width and inhibited interface recombination. As a result, the power conversion efficiency (PCE) of the binary OSCs comprising PM6: BTP‐ec9 exhibits an increase from 18.2% to 19.3%, placing it among the one of the highest PCE values. Moreover, this approach demonstrated notable applicability for another CILs, as well as various OSCs systems. Overall, this research underscores the importance of regulating and modifying CILs to fully exploit their potential in OSCs devices, while laying the groundwork for optimizing their efficiency and stability. [ABSTRACT FROM AUTHOR]

The multi‐component strategy has proven effective in advancing the performance of organic photovoltaics (OPVs), enhancing photocurrent and fill factor through spectral complementarity and morphology optimization. However, the open‐circuit voltage (VOC) mechanism in multi‐component systems lacks systematic investigation. In this study, we explore the influence of alloy‐like phases on energy level distribution and energy loss mechanisms in multi‐component OPVs. Appropriate modulation of donor alloy‐like phases maintains the original intermolecular stacking, enhances component compatibility, reduces acceptor aggregation, and improves acceptor phase purity, mitigating non‐radiative recombination losses. Additionally, suitable alloy‐like phase modulation elevates charge transfer (CT) states, reducing the gap between CT and local exciton state, lowering reorganization energy, and alleviating radiative recombination loss below the bandgap. Through synergistic optimization (layer‐by‐layer method with solid additive), ternary devices based on Y6 acceptor achieve a notable 19.41% power conversion efficiency, offering new insights for the analysis of the energy loss of the multi‐component OPVs. [ABSTRACT FROM AUTHOR]

BackgroundHefei Advanced Light Facility (HALF) is a fourth-generation synchrotron radiation light source based on diffraction-limited storage ring. The timing system provides trigger signals for the HALF injector, storage ring and beamline, coordinates injection and beam measurement, and achieves filling of the storage ring bucket with any designated bunch pattern.PurposeThis study aims to design a timing system for HALF to reduce the trigger signal jitter of the HALF device to less than 30 ps, and stabilize the signal drift caused by the optical fiber length change.MethodsBased on the MTCA.4 event-driven products from Micro-Research Finland Oy (MRF), the event timing technology scheme was adopted to implement the timing system. Appropriate system frequencies for electron gun, microwave system and storage ring were selected to achieve different modes of storage ring bucket filling scheme. The timing system software was developed under Experimental Physics and Industrial Control System (EPICS) to coordinate with the control system of HALF, including an EPICS driver, database records, and operation interfaces. Delay compensation was applied to signal drift caused by the variation of optical fiber length. Finally, a prototype of the timing system was developed for performance tests.Results & ConclusionsThe results show that the jitter of the trigger signal is less than 24 ps, and the signal drift is controlled at about 3 ps after delay compensation, both meet the design requirements of HALF timing system.

The rational design of guest small molecule donors for ternary organic solar cells is still a challenge. Herein, we designed and synthesized two novel small-molecule donor third components using ethyl (QxBE) and isopropyl formate (QxBC) substituted quinoxalines as acceptor units. The stronger electron withdrawing ability of the isopropyl formate group and the small torsion angle provide QxBC with obviously red-shifted absorption and tighter molecular packing than QxBE. Both molecules exhibited complementary absorption and good miscibility with the host PM6:L8-BO blend system. The incorporation of these two molecules into the PM6:L8-BO system facilitated a fibrous network structure, enhanced crystallinity and optimized vertical phase distribution. This results in suppressed charge recombination and balanced charge transport ability. Consequently, QxBC-based ternary OSCs exhibited simultaneous enhancements in open-circuit voltage (VOC) (0.898 V), short-circuit current (JSC) (26.49 mA cm−2), FF (80.04%) and PCE (19.04%), representing record values for ternary OSCs with small-molecule donors as the third component. Furthermore, the storage/thermal stability of ternary OSCs has been significantly improved. These results imply in-depth insights into the structure–property relationship of SMD third components manipulated by the middle bridge unit, and provide new strategies for effective molecular design of SMD third components toward high-performance ternary OSCs. [ABSTRACT FROM AUTHOR]

BackgroundHefei Light Source (HLS-II) is a dedicated synchrotron radiation source with featured the characteristics spectrum in vacuum ultraviolet and soft X-rays regions. The user's experiment efficiency and data processing efficiency are the principal indicators of HLS-II operation.PurposeThis study aims to develop an experimental data management system based on SciCat to improve the user's experimental and data processing efficiency.MethodsAs the core component of HLS-II experimental data management system, the metadata system was designed and developed within the framework of SciCat, an open source metadata catalog framework used to realize the unified management of the whole life cycle of experimental data of large scientific devices. Data acquisition service, metadata system, file storage system and data analysis platform were integrated into SciCat, and the hierarchical data format 5 (HDF5) was adopted as the standard experimental data format. Interface between existing user service systems and SciCat was implemented to achieve the management of the whole experiment and experimental data lifecycle, including user authentication, proposal application, expert approval, machine time schedule, data acquisition, data storage, data analysis and data publication.Results & ConclusionsThe system has been deployed and functionally tested at the soft X-ray microscopy experimental station of HLS-II, satisfying all design requirements.