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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]

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]

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 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]