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Mixed‐halide perovskites show promising applications in tandem solar cells owing to their adjustable bandgap. One major obstacle to their commercialization is halide phase segregation, which results in large open‐circuit voltage deficiency and J‐V hysteresis. However, the ambiguous interplay between structural origin and phase segregation often results in aimless and unspecific optimization strategies for the device's performance and stability. An atomic scale is directly figured out the abundant Ruddlesden‐Popper anti‐phase boundaries (RP‐APBs) within a CsPbIBr2 polycrystalline film and revealed that phase segregation predominantly occurs at RP‐APB‐enriched interfaces due to the defect‐mediated lattice strain. By compensating their structural lead halide, such RP‐APBs are eliminated, and the decreasing of strain can be observed, resulting in the suppression of halide phase segregation. The present work provides the deciphering to precisely regulate the perovskite atomic structure for achieving photo‐stable mixed halide wide‐bandgap perovskites of high‐efficiency tandem solar cell commercial applications. [ABSTRACT FROM AUTHOR]

Zeolite Beta single crystals with intracrystalline hierarchical porosity at macro‐, meso‐, and micro‐length scales can effectively overcome the diffusion limitations in the conversion of bulky molecules. However, the construction of large zeolite Beta single crystals with such porosity is a challenge. We report herein the synthesis of hierarchically ordered macro‐mesoporous single‐crystalline zeolite Beta (OMMS‐Beta) with a rare micron‐scale crystal size by an in situ bottom‐up confined zeolite crystallization strategy. The fully interconnected intracrystalline macro‐meso‐microporous hierarchy and the micron‐sized single‐crystalline nature of OMMS‐Beta lead to improved accessibility to active sites and outstanding (hydro)thermal stability. Higher catalytic performances in gas‐phase and liquid‐phase acid‐catalyzed reactions involving bulky molecules are obtained compared to commercial Beta and nanosized Beta zeolites. The strategy has been extended to the synthesis of other zeolitic materials, including ZSM‐5, TS‐1, and SAPO‐34. [ABSTRACT FROM AUTHOR]

Zeolite Beta single crystals with intracrystalline hierarchical porosity at macro‐, meso‐, and micro‐length scales can effectively overcome the diffusion limitations in the conversion of bulky molecules. However, the construction of large zeolite Beta single crystals with such porosity is a challenge. We report herein the synthesis of hierarchically ordered macro‐mesoporous single‐crystalline zeolite Beta (OMMS‐Beta) with a rare micron‐scale crystal size by an in situ bottom‐up confined zeolite crystallization strategy. The fully interconnected intracrystalline macro‐meso‐microporous hierarchy and the micron‐sized single‐crystalline nature of OMMS‐Beta lead to improved accessibility to active sites and outstanding (hydro)thermal stability. Higher catalytic performances in gas‐phase and liquid‐phase acid‐catalyzed reactions involving bulky molecules are obtained compared to commercial Beta and nanosized Beta zeolites. The strategy has been extended to the synthesis of other zeolitic materials, including ZSM‐5, TS‐1, and SAPO‐34. [ABSTRACT FROM AUTHOR]