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Hole transport materials (HTMs) are essential for improving the stability and efficiency of perovskite solar cells (PSCs). In this study, we have designed and synthesized a novel organic small molecule HTM, cor‐(DPA)5, characterized by a bowl‐shaped core with symmetric five diphenylamine groups. Compared to already‐known HTMs, the bowl‐shaped and relatively compact structure of cor‐(DPA)5 facilitates intermolecular π–π interactions, promotes film formations, and enhances charge transport. Consequently, the cor‐[DPA(2)]5 HTM exhibits high charge mobility, exceptional hydrophobicity, and a significantly elevated glass transition temperature. Superior to previously reported HTMs such as spiro‐OMeTAD and cor‐OMePTPA, our newly synthesized cor‐(DPA)5 HTM is free from any ionic dopants. As a result, the dopant‐free cor‐[DPA(2)]5‐based PSC demonstrates an impressive efficiency of 24.01 %, and exhibits outstanding operational stability. It retains 96 % after continuous exposure to 1 sun irradiation for 800 hours under MPP (maximum power point) tracking in ambient air. These findings present a structurally compact novel HTM and exemplify a new approach to the molecular design of HTM for the development of stable and effective PSCs. [ABSTRACT FROM AUTHOR]

A double–heptagon–containing C70H6 (dihept-C70H6) was isolated and unambiguously characterized in the soot of low-pressure combustion, which shares the identical heptagonal cage as dihept-C70Cl6 previously identified in the products of carbon arc, and thus represents the first nonclassical fullerene isolable in both carbon arc and combustion. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: Because of its unsaturated bonds, C60 is susceptible to polymerize into dimers. The implications of nitrogen doping on the geometrical and electronic structure of C60 dimers have been ambiguous for years. A quarter‐century after the discovery of azafullerene dimer (C59N)2, we reported its single crystallographic structure in 2019. Herein, the unambiguous crystal structure information of (C59N)2 is elucidated specifically, revealing that the inter‐cage C—C single bond length of (C59N)2 is comparable with that of an ordinary C(sp3)‐C(sp3) single bond, and that the most stable conformer of (C59N)2 is gauche‐conformer with a dihedral angle of 66°. To amend the structural deviations, geometrical structure of (C59N)2 is optimized by a B3LYP‐D3BJ function, which is proved to be more consistent with its single crystal structure than those by the commonly used B3LYP function. Moreover, the calculation method is also suitable for other representative fullerene dimers, such as (C60)2 and its divalent anion. Additionally, the dissociation of (C59N)2 at 473 K under mass spectrometric conditions suggests the inter‐cage C—C bond is relatively weaker than an ordinary C—C single bond, which can be explained by the interaction energies of inter‐cages. [ABSTRACT FROM AUTHOR]

All previously reported C70 isomers have positive curvature and contain 12 pentagons in addition to hexagons. Herein, we report a new C70 species with two negatively curved heptagon moieties and 14 pentagons. This unconventional heptafullerene[70] containing two symmetric heptagons, referred to as dihept‐C70, grows in the carbon arc by a theoretically supported pathway in which the carbon cluster of a previously reported C66 species undergoes successive C2 insertion via a known heptafullerene[68] intermediate with low energy barriers. As identified by X‐ray crystallography, the occurrence of heptagons facilitates a reduction in the angle of the π‐orbital axis vector in the fused pentagons to stabilize dihept‐C70. Chlorination at the intersection of a heptagon and two adjacent pentagons can greatly enlarge the HOMO–LUMO gap, which makes dihept‐C70Cl6 isolable by chromatography. The synthesis of dihept‐C70Cl6 offers precious clues with respect to the fullerene formation mechanism in the carbon‐clustering process. [ABSTRACT FROM AUTHOR]

Two novel chiral lanthanide–sulfate frameworks,Ln4(OH)4(SO4)4(H2O)3[Ln = Y (1) and Er (2)],have been synthesized under hydrothermal reactions. X-ray crystalstructure analyses reveal that 1and 2areisomorphous and crystallize in the orthorhombic space group P2(1)2(1)2(1). Both compounds are isostructural and containhelical tubes and channels constructed from double left- and right-handedhelical chains. Further structural analysis reveals that compound 1is a high connected binodal net by assigning the SO42–anion as a three-connected node and the{Y4} cluster as a 12-connected node. Furthermore, the infrared,thermogravimetric analysis, and powder X-ray diffraction propertieswere also studied. [ABSTRACT FROM AUTHOR]

Herein, corannulene‐based quintuple [6]helicenes (Q[6]H‐1 and Q[6]H‐2) and [7]helicene (Q[7]H) were synthesized via penta‐fold Heck and Mallory reaction. Notably, Q[7]H represents the highest reported helicene based on corannulene. X‐ray crystallography reveals that Q[6]H‐2 adopts a propeller‐shaped conformation with a well‐preserved corannulene core, while Q[6]H‐1 and Q[7]H exhibit quasi‐propeller‐shaped conformations. Upon heating, conformer Q[6]H‐1 undergoes conversion to the thermodynamically more stable conformer Q[6]H‐2, whereas conformer Q[7]H remains unchanged due to larger steric congestion. Racemization of the enantiomer of Q[6]H‐1 and conformational conversion were observed simultaneously at elevated temperature, with DFT studies indicating a racemization barrier of 32.06 kcal ⋅ mol−1. In contrast, the racemization barrier for Q[6]H‐2 was calculated to be 45.46 kcal ⋅ mol−1, indicating exceptional chiral stability. Surprisingly, the bowl inversions of Q[6]H‐1 and Q[6]H‐2 conformers are somewhat inhibited by the helical blades, whereas this was not observed for other possible conformers of Q[6]H. These results first demonstrated that subtle conformational variations can lead to significant changes in chiral stability and bowl inversions of multiple helicenes. Due to the well‐preserved corannulene core, propeller‐shaped conformation and electron complementarity, Q[6]H‐2 can recognize fullerenes in both solution and solid state, which is a rare instance of co‐crystallization assembly between multiple helicenes and fullerenes. [ABSTRACT FROM AUTHOR]

A pyrrole-fused analogue of warped nanographene, designated as deca-nitrogen doped 'WNG' (azaWNG), was synthesized through the annular fusion of decapyrroylcorannulene. The resulting azaWNG exhibited extremely limited solubility in common organic solvents and was characterized solely by mass spectrometry. Theoretical calculations revealed that azaWNG has a sunflower-like molecular structure with electron-deficient corannulene as the core and electron-rich pyrrole as the petals, demonstrating a significantly narrower energy gap compared to all-carbon WNG. To improve its solubility and facilitate precise structural characterization, iodine monochloride was utilized for edge-perchlorination of azaWNG, enabling successful separation and purification of chlorinated azaWNG in solution phase. X-ray crystallography analysis unequivocally confirmed that edge-perchlorinated azaWNG contains 5 heptagons and 11 pentagons embedded within the warped π skeleton. Cyclic voltammetry measurements indicated that the first oxidation potential of azaWNG is -0.59 V, representing the lowest value reported for any previously studied aza-nanographene. Consequently, azaWNG can be readily oxidized by AgPF 6 or even atmospheric oxygen to yield stable oxidation states, as corroborated by UV/Visible absorption spectroscopy; this behavior is attributed to the fusion of ten pyrroles around corannulene. This work marks the first instance of nitrogen doping in WNG (C 80 H 30 ), underscoring the significant modification to electronic structure induced by such doping., (© 2025 Wiley-VCH GmbH.)