
Strain relaxation in halide perovskites via 2D/3D perovskite heterojunction formation
Sci Adv. 2025 Jun 27;11(26):eadu3459. doi: 10.1126/sciadv.adu3459. Epub 2025 Jun 27.
ABSTRACT
Applying mechanical strain and strain engineering to halide perovskites has endowed them with intriguing properties. However, an in-depth understanding of mechanical strain, including residual strain in halide perovskites, remains incomplete, coupled with the critical challenge of decoupling strain effects from other interferences. Here, we examine the relaxation of residual tensile strain in three-dimensional (3D) halide perovskites through 2D/3D perovskite heterojunction formation. The 2D perovskite induces structural fragmentation in 3D perovskites, facilitating plastic relaxation of tensile strain. By isolating extrinsic crystalline phase interference and exciton-related optical disturbances, we observe that 3D perovskites retain high crystallinity only with moderate tensile strain relaxation. This moderate relaxation enhances optoelectronic properties in 3D perovskites, including broadened band-to-band absorption and prolonged charge carrier lifetime, markedly contributing to an increase in the maximum attainable power conversion efficiency in photovoltaic devices. Our findings outline conditions for strain relaxation that optimize optoelectronic properties, advancing strain engineering in halide perovskites.
PMID:40577478 | PMC:PMC12204152 | DOI:10.1126/sciadv.adu3459
Tunable Self-Assembly of Decanuclear Ni(II) Carbonato Clusters with a Hydroxyquinolinato Shell: Robust Porous Networks with Reversible Solvent-/Temperature-Driven Phase Transitions and Selective Gas Separation
J Am Chem Soc. 2025 Jun 4;147(22):19073-19083. doi: 10.1021/jacs.5c04096. Epub 2025 May 27.
ABSTRACT
The utilization of molecular metal clusters as building units of noncovalent porous materials (NPMs) is a promising strategy, combining the versatile functionality of organic and inorganic subunits with the softness and flexibility of molecular solids controlled by noncovalent interactions. However, the development of robust porous functional frameworks based on self-assembly driven by noncovalent forces is still highly challenging. Herein, we report the synthesis and characterization of a discrete decanuclear Ni(II) hydroxyquinolinato-carbonato cluster, [Ni10(μ6-CO3)4(L)12], which, depending on the crystallization conditions, self-assembles into either of two microporous frameworks: diamondoid WUT-1(Ni) and pyrite WUT-2(Ni). The transitions between both polymorphs can also be selectively triggered by temperature or exposure to vapors of a particular organic solvent, which is accompanied by the easy recovery of crystallinity by the materials from the noncrystalline phase. Moreover, both materials show excellent robustness toward various chemical environments, including air/moisture and water stability, and demonstrate interesting gas adsorption properties. Remarkably, WUT-1(Ni) exhibits significant enhancement in gas uptake compared to the previously reported isostructural Zn(II) analogue, WUT-1(Zn), representing one of the highest H2 uptakes among NPMs. In turn, tighter voids of the ultramicroporous WUT-2(Ni) framework facilitate selective interactions with gas molecules, resulting in outstanding selectivity in the adsorption of CO2 over CH4 and N2. The presented studies demonstrate the profound role of the character of metal centers on the self-assembly of isostructural nanoclusters as well as properties of the resulting microporous frameworks.
PMID:40421976 | PMC:PMC12147118 | DOI:10.1021/jacs.5c04096
Engineering Bodipy-Based Metal-Organic Frameworks for Efficient Full-Spectrum Photocatalysis in Amide Synthesis
Angew Chem Int Ed Engl. 2025 Jun 10;64(24):e202505405. doi: 10.1002/anie.202505405. Epub 2025 Apr 14.
ABSTRACT
Developing photocatalysts that can efficiently utilize the full solar spectrum is a crucial step toward transforming sustainable energy solutions. Due to their light absorption limitations, most photo-responsive metal-organic frameworks (MOFs) are constrained to the ultraviolet (UV) and blue light regions. Expanding their absorption to encompass the entire solar spectrum would unlock their full potential, greatly enhancing efficiency and applicability. Here, we report the design and synthesis of a series of highly stable boron-dipyrromethene (bodipy)-based MOFs (BMOFs) by reacting dicarboxyl-functionalized bodipy ligands with Zr-oxo clusters. Leveraging the acidity of the methyl groups on the bodipy backbone, we expanded the conjugation system through a solid-state condensation reaction with various aldehydes, achieving full-color absorption, thereby extending the band edge into the near-infrared (NIR) and infrared (IR) regions. These BMOFs demonstrated exceptional reactivity and recyclability in heterogeneous photocatalytic activities, including C─H bond activation of saturated aza-heterocycles and C─N bond cleavage of N,N-dimethylanilines to produce amides under visible light. Our findings highlight the transformative potential of BMOFs in photocatalysis, marking a significant leap forward in the design of advanced photocatalytic materials with tunable properties.
PMID:40192658 | PMC:PMC12144902 | DOI:10.1002/anie.202505405