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Long‐term stability has become the major obstacle for the successful large‐scale application of perovskites devices. Owing to the ionic nature of metal‐halide perovskites, the interfacial ion diffusion can induce irreversible degradation under operational conditions, which presents a great challenge to realize stable perovskite solar modules. Here, a diphenylphosphine oxide compound, ethane‐1,2‐diylbis(diphenylphosphine oxide) (DPPO) is introduced to coordinate with lead iodide and form a cross‐linked 1D Pb3I6‐DPPO (1D‐PbI2) complex. These judiciously designed cross‐linked nonionic low‐dimensional lead halide/organic adducts can passivate the defects of perovskite while acting as a robust ion diffusion barrier, thus significantly improving the electronic quality and intrinsic stability of perovskite films. As a result, high‐performance inverted (p‐i‐n) solar modules with a champion efficiency approaching 19% (a certified stabilized efficiency of 17.8%) for active device areas above 17 cm2 without the use of antisolvents, accompanied by outstanding operational stability under heat stress and continuous illumination are achieved. [ABSTRACT FROM AUTHOR]

Ether‐based electrolytes are commonly used in Li–O2 batteries (LOBs) because of their relatively high stability. But they are still prone to be attacked by superoxides or singlet oxygen via hydrogen abstract reactions, which leads to performance decaying during long‐term operation. Herein we propose a methylated cyclic ether, 2,2,4,4,5,5‐hexamethyl‐1,3‐dioxolane (HMD), as a stable electrolyte solvent for LOBs. Such a compound does not contain any hydrogen atoms on the alpha‐carbon of the ether, and thus avoids hydrogen abstraction reactions. As the result, this solvent exhibits excellent stability with the presence of superoxide or singlet oxygen. In addition the CO2 evolution during charge process is prohibited. The LOB with HMD‐based electrolyte was able to run up to 157 cycles, 4 times more than with 1,3‐dioxolane (DOL) or 1,2‐dimethoxyethane (DME) based electrolytes. [ABSTRACT FROM AUTHOR]

Ether‐based electrolytes are commonly used in Li–O2 batteries (LOBs) because of their relatively high stability. But they are still prone to be attacked by superoxides or singlet oxygen via hydrogen abstract reactions, which leads to performance decaying during long‐term operation. Herein we propose a methylated cyclic ether, 2,2,4,4,5,5‐hexamethyl‐1,3‐dioxolane (HMD), as a stable electrolyte solvent for LOBs. Such a compound does not contain any hydrogen atoms on the alpha‐carbon of the ether, and thus avoids hydrogen abstraction reactions. As the result, this solvent exhibits excellent stability with the presence of superoxide or singlet oxygen. In addition the CO2 evolution during charge process is prohibited. The LOB with HMD‐based electrolyte was able to run up to 157 cycles, 4 times more than with 1,3‐dioxolane (DOL) or 1,2‐dimethoxyethane (DME) based electrolytes. Full methyl jacket: A fully methylated cyclic ether 4,4,5,5‐hexamethyl‐1,3‐dioxolane is used as an electrolyte solvent for Li–O2 batteries. It exhibits excellent stability in the presence of superoxide or singlet oxygen because all the active α‐H atoms are substituted with methyl groups. The cycling performance is 4 times greater that of conventional ether electrolytes. [ABSTRACT FROM AUTHOR]

The radical-initiated C-H bond functionalization of cyclic ethers with imines represents an efficient way to form C-C bonds and construct 1,2-amino ethers. Despite being a net redox-neutral process, most examples require excess amounts of radical reagents or oxidants to continuously generate the radical species. Herein, we report an atom-economic protocol for the radical addition of cyclic ethers to imines without the need for any oxidant, metal salt, delicate catalyst, or UV irradiation. In the presence of small amounts of AIBN (2 mol-%), tetrahydrofuran smoothly undergoes the reaction with a variety of imines to afford 1,2-amino ethers in moderate to good yields. Preliminary mechanistic studies suggest that this transformation likely proceeds through a radical chain process with the hydrogen atom abstraction as the rate-determining step. [ABSTRACT FROM AUTHOR]

[Display omitted] • PNCs-radical core/shell structure was prepared by P -type organic radical polymer. • This structure improves the stability of PNCs with charge transfer processes. • The stable PNCs-radical core/shell complex demonstrate superb reduction ability. • This strategy could promote the performance of PNCs based n-i-p solar cells. Balancing the stability and interfacial charge transfer (CT) ability of perovskite nanocrystals (PNCs) are the most challenging issue confronting their practical application in photoelectrochemistry (PEC) fields. Here, an efficient surface capping strategy is introduced relying on a set of air-stable nitroxide-based organic radical polymers with well-matched energy levels towards CsPbBr 3 nanocrystals. The native ligand oleyl amine and oleic acid were readily replaced by radical polymers because of their high-affinity properties. The resulting radical polymer coated PNCs exhibit exceptional tolerance to water, thermal, and UV illumination with remarkable CT processes. The versatility and immense practical utility of such stable PNCs-radical core/shell structure are showcased by the halogen exchange between PNCs/radical and aryl chlorides at ambient temperature, demonstrating superb reduction ability of this complex. Besides, this strategy was also employed to improve the power conversion efficiency and stability of PNCs based solar cells. This approach imparts exceptional photoelectrochemical stability and catalytic activity to the nanocrystals with excellent interfacial CT efficiency. [ABSTRACT FROM AUTHOR]

Taxi drivers often take much time to navigate the streets to look for passengers, which leads to high vacancy rates and wasted resources. Empty taxi cruising remains a big concern for taxi companies. Analyzing the pick-up point selection behavior can solve this problem effectively, providing suggestions for taxi management and dispatch. Many studies have been devoted to analyzing and recommending hotspot regions of pick-up points, which can make it easier for drivers to pick-up passengers. However, the selection of pick-up points is complex and affected by multiple factors, such as convenience and traffic management. Most existing approaches cannot produce satisfactory results in real-world applications because of the changing travel demands and the lack of interpretability. In this paper, we introduce a visual analytics system, T-PickSeer, for taxi company analysts to better explore and understand the pick-up point selection behavior of passengers. We explore massive taxi GPS data and employ an overview-to-detail approach to enable effective analysis of pick-up point selection. Our system provides coordinated views to compare different regularities and characteristics in different regions. Also, our system assists in identifying potential pick-up points and checking the performance of each pick-up point. Three case studies based on a real-world dataset and interviews with experts have demonstrated the effectiveness of our system. [ABSTRACT FROM AUTHOR]

Music streaming services are increasingly popular among younger generations who seek social experiences through personal expression and sharing of subjective feelings in comments. However, such emotional aspects are often ignored by current platforms, which affect the listeners' ability to find music that triggers specific personal feelings. To address this gap, this study proposes a novel approach that leverages deep learning methods to capture contextual keywords, sentiments, and induced mechanisms from song comments. The study augments a current music app with two features, including the presentation of tags that best represent song comments and a novel map metaphor that reorganizes song comments based on chronological order, content, and sentiment. The effectiveness of the proposed approach is validated through a usage scenario and a user study that demonstrate its capability to improve the user experience of exploring songs and browsing comments of interest. This study contributes to the advancement of music streaming services by providing a more personalized and emotionally rich music experience for younger generations. [ABSTRACT FROM AUTHOR]

A metal‐free and oxidant‐free method for the one‐pot preparation of quinazolin‐4(3H)‐ones enabled by electrochemical oxidation is described. Together with 2‐aminobenzamides, a variety of aldehydes were successfully applied to an acid‐catalyzed annulation and direct anodic oxidation cascade, affording structurally diverse quinazoline‐4(3H)‐ones in good to excellent yields. Additionally, certain alcohols can be directly applied instead of the corresponding aldehydes to achieve the same final products with the assistance of an electrolysis mediator (TEMPO). The reaction mechanism was carefully examined and the results strongly suggest that the direct and indirect oxidation go through different pathways. As an efficient and environmentally friendly access to a broad range of quinazolin‐4(3H)‐ones, the synthetic utility of this method was demonstrated by gram‐scale operation, as well as the preparation of bioactive mackinazolinone and truncated erlotinib. [ABSTRACT FROM AUTHOR]

The self‐assembled hole transporting molecules (SAHTMs) bearing anchoring groups have been established as the hole transporting layers (HTLs) for highly efficient p–i–n perovskite solar cells (PSCs), yet their stability and engineering at the molecular level remain challenging. A topological design of highly anisotropic aligned SAHTM‐based HTLs for operationally stable PSCs that exhibit exceptional solar‐to‐electric power conversion efficiencies (PCEs) is demonstrated. The judiciously designed multifunctional self‐assembled molecules comprise the donor–acceptor subunit for hole transporting and the phosphonic acid group for anchoring, realizing face‐on π‐stacking parallel to the transparent conductive oxide substrate. The high affinity of SAHTMs to the multi‐crystalline perovskite thin film benefits passivating the perovskite buried interface, strengthening interfacial contact while facilitating interfacial hole transfer. Consequently, highly efficient p–i–n PSC devices are obtained with a champion PCE of 23.24% and outstanding operational stability toward various environmental factors including long‐term full sunlight soaking at evaluated temperatures. Perovskite solar modules with a champion efficiency approaching 20% are also fabricated for an active device area above 17 cm2. [ABSTRACT FROM AUTHOR]

[Display omitted] • TPA-BA modification results in improved interfacial energy band alignment. • TPA-BA modification reduces interfacial chemical reactivity. • The TPA-BA-modified devices achieve a power conversion efficiency of 22.25%. • TPA-BA-based devices remained stable after illumination and thermal aging tests. Nickel oxide (NiO x) is one of the most promising inorganic hole transport layers for perovskite solar cells (PSCs) due to its low cost, high hole mobility, and superior stability. However, the mismatched energy level and undesirable chemical reaction at the NiO x /perovskite interface limit the performance of NiO x -based PSCs. Herein, a p- type semiconductor TPA-BA is explored to modify the NiO x /perovskite interface and form an intermediate hole transport layer (HTL) between NiO x and perovskite for efficient and efficient stable PSCs. This molecule comprises triphenylamine and carboxyl function groups, which can be anchored on the NiOx surface and facilitate the hole transfer between the perovskite and NiO x layer by minimizing the interfacial band energy offset. Furthermore, the bi-layered NiO x HTL exhibited reduced chemical reactivity at NiO x /perovskite interface, which would otherwise lead to detrimental perovskite degradation. Thus, a champion PSC device with an open-circuit voltage value up to 1.15 V and a power conversion efficiency of 22.25% was demonstrated-a high value for NiO x -based PSCs. More importantly, the intermediated HTL modified PSCs exhibit significantly improved device stability compared with un-modified PSCs, retaining over 90 % of their initial efficiencies after 1000-h continuous operation under 1 sun illumination and thermal aging at 85 °C respectively. This work renders the promise of TPA-BA as the intermediated HTL in between p -type metal oxide and perovskite for optoelectronic applications. [ABSTRACT FROM AUTHOR]