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New mechanisms of controlled growth of one-dimensional (1D) metal-organic framework (MOF) nano- and super-structures under size-confinement and surface directing effects have been discovered. Through applying interfacial synthesis templated by track-etched polycarbonate (PCTE) membranes, congruent polycrystalline zeolitic imidazolate framework-8 (ZIF-8) solid nanorods and hollow nanotubes were found to form within 100 nm membrane pores, while single crystalline ZIF-8 nanowires grew inside 30 nm pores, all of which possess large aspect ratios up to 60 and show preferential crystal orientation with the {100} planes aligned parallel to the pore's long axis. Our findings provide a generalizable methodology for controlling size, morphology, and lattice orientation of MOF nanomaterials.

Photocatalytic water splitting requires separation of the mixed H2 and O2 products and is often hampered by the sluggish O2-producing half reaction. Herein, we report, for the first time, a novel approach to address these issues by coupling the H2-producing half reaction with value-added benzylamine oxidation reaction using metal-organic framework (MOF) composites. Upon MOF photoexcitation, the electrons rapidly reduce the protons to generate H2 and the holes promote considerable benzylamine oxidation to N-benzylbenzaldimine with high selectivity. Further experimental characterizations and theoretical calculation reveal that the highly conjugated s-triazine strut in the MOF structure is crucial to the efficient charge separation and excellent photocatalytic activity.

Metal–organic frameworks (MOFs) are an emerging class of porous materials with potential applications in gas storage, separations, catalysis, and chemical sensing. Despite numerous advantages, applications of many MOFs are ultimately limited by their stability under harsh conditions. Herein, the recent advances in the field of stable MOFs, covering the fundamental mechanisms of MOF stability, design, and synthesis of stable MOF architectures, and their latest applications are reviewed. First, key factors that affect MOF stability under certain chemical environments are introduced to guide the design of robust structures. This is followed by a short review of synthetic strategies of stable MOFs including modulated synthesis and postsynthetic modifications. Based on the fundamentals of MOF stability, stable MOFs are classified into two categories: high-valency metal–carboxylate frameworks and low-valency metal–azolate frameworks. Along this line, some representative stable MOFs are introduced, their structures are described, and their properties are briefly discussed. The expanded applications of stable MOFs in Lewis/Brønsted acid catalysis, redox catalysis, photocatalysis, electrocatalysis, gas storage, and sensing are highlighted. Overall, this review is expected to guide the design of stable MOFs by providing insights into existing structures, which could lead to the discovery and development of more advanced functional materials.

Stable metal–organic frameworks (MOFs) with high resistance to harsh chemical environments are reviewed with regard to recent progress in their research and development. Fundamental mechanisms of MOF stability, design and synthesis of stable MOF architectures, and their latest applications are summarized, providing a fundamental outline for the discovery of new stable MOFs.

Visible light photocatalysis has evolved over the last decade into a widely used method in organic synthesis. For many important transformations, such as cross-coupling reactions, alpha-amino functionalizations, cycloadditions, ATRA reactions, or fluorinations, photocatalytic variants have been reported. In this review, we try to compare classical and photocatalytic procedures for selected classes of reactions and highlight their advantages and limitations. In many cases, the photocatalytic reactions proceed at milder reaction conditions, typically at room temperature, and stoichiometric reagents are replaced by simple oxidants or reductants, like air oxygen or amines. This way, besides providing alternative protocols for established transformations that allow a broadening of the substrate scope, also new transformations become possible, especially by merging photocatalysis with organo- or metal catalysis. Does visible light photocatalysis make a difference in organic synthesis? The prospect to shuttle electrons back and forth to substrates and intermediates or to selectively transfer energy through a visible light absorbing photocatalyst holds the promise to improve current protocols in radical chemistry and to open up new avenues by accessing reactive species hitherto unknown.

BiOCl nanosheets/TiO₂ nanotube arrays heterojunction UV photodetector (PD) with high performance is fabricated by a facile anodization process and an impregnation method. The heterojunction at the interface and the internal electric fields in the BiOCl nanosheets faciliate the separation of photogenerated charge carriers and regulate the transportation of the electrons. Compared with the large dark current (≈10⁻⁵ A), low on/off ratio (8.5), and slow decay time (>60 s) of the TiO₂ PD, the optimized heterojunction PD (6-BiOCl–TiO₂) yields dramatically decreased dark current (≈1 nA), ultrahigh on/off ratio (up to 2.2 × 10⁵), and fast decay speed (0.81 s) under 350 nm light illumination at −5 V. Moreover, it exhibits an increased responsivity of 41.94 A W⁻¹, a remarkable detectivity (D*) of 1.41 × 10¹⁴ Jones, and a high linear dynamic range of 103.59 dB. The loading amount and growth orientations of the BiOCl nanosheets alter the roles of the self-induced internal electric field in regulating the behaviors of the charge carriers, thus affecting the photoelectric properties of the heterojunction PDs. These results demonstrate that rational construction of novel heterojunctions hold great potentials for fabricating photodetectors with high performance.

A BiOCl–TiO₂ heterojunction UV photodetector with high performance is fabricated. Heterojunctions formed between BiOCl nanosheets and TiO₂ nanotube arrays improve the UV photoresponses and response speed of TiO₂ film photodetectors. The loading amount and growth orientation of BiOCl nanosheets on the TiO₂ film have great influences on the photoelectric performance of the heterojunction photodetector.

Photocatalytic hydrogen production is crucial for solar-to-chemical conversion process, wherein high-efficiency photocatalysts lie in the heart of this area. A photocatalyst of hierarchically mesoporous titanium phosphonate based metal–organic frameworks, featuring well-structured spheres, a periodic mesostructure, and large secondary mesoporosity, are rationally designed with the complex of polyelectrolyte and cathodic surfactant serving as the template. The well-structured hierarchical porosity and homogeneously incorporated phosphonate groups can favor the mass transfer and strong optical absorption during the photocatalytic reactions. Correspondingly, the titanium phosphonates exhibit significantly improved photocatalytic hydrogen evolution rate along with impressive stability. This work can provide more insights into designing advanced photocatalysts for energy conversion and render a tunable platform in photoelectrochemistry.

A multi-structured photocatalyst: A metal–organic framework (MOF) nanostructure synthesized by a surfactant-directed strategy features a stable framework of titanium phosphates, a well-defined sphere, and hierarchical nanopores. These features ensure competitive photoactivity in evolving hydrogen under both visible light and full-spectrum simulator irradiation, along with high durability.

Metal–organic frameworks (MOFs) are intriguing platforms with multiple functionalities. Additional functionalization of MOFs generates novel materials for various applications. Here, three main topics are examined regarding the functionalization of MOFs for use as photoactive materials. The first is chemical approaches for postsynthetic modification of the metal clusters and organic linkers in MOFs; that is, sites on pore surfaces and chemical trapping of photoactive moieties within the pores, which create materials with chemical functionalities for water splitting and CO₂ reduction by light. The second topic focuses on the functionalization of MOFs for photochemical response and the versatile applications of such materials. State-of-the-art research on functionalizing MOFs through photochemical reactions on the pore surface and within the pores as guests is also summarized. The third topic introduces the functionalization of MOFs for photofunctional materials, including photoluminescent tuning and integration, photoluminescent LED devices and barcodes, and photophysical applications for chemical sensing. Finally, conclusions and perspectives on the fields are given.

The photoactive properties of functionalized metal–organic frameworks are reviewed for photochemical and photophysical applications, including photocatalytic solar fuel production, photochemical response, and photoluminescent tuning and sensing.

It is highly desirable yet remains challenging to improve the dispersion and usage of noble metal cocatalysts, beneficial to charge transfer in photocatalysis. Herein, for the first time, single Pt atoms are successfully confined into a metal–organic framework (MOF), in which electrons transfer from the MOF photosensitizer to the Pt acceptor for hydrogen production by water splitting under visible-light irradiation. Remarkably, the single Pt atoms exhibit a superb activity, giving a turnover frequency of 35 h⁻¹, ≈30 times that of Pt nanoparticles stabilized by the same MOF. Ultrafast transient absorption spectroscopy further unveils that the single Pt atoms confined into the MOF provide highly efficient electron transfer channels and density functional theory calculations indicate that the introduction of single Pt atoms into the MOF improves the hydrogen binding energy, thus greatly boosting the photocatalytic H₂ production activity.

Metal–organic frameworks (MOFs) are promising templates to stabilize single atoms for catalysis. A porphyrinic MOF is used as template to obtain single platinum atoms for the first time. The obtained catalyst exhibits superb visible-light photocatalytic efficiency in hydrogen production and the turnover frequency value of single platinum (Pt) atoms is ≈30 times than that of MOF-stabilized platinum nanoparticles.

A wide range of light absorption and rapid electron–hole separation are desired for efficient photocatalysis. Herein, on the basis of a semiconductor-like metal–organic framework (MOF), a Pt@MOF/Au catalyst with two types of metal–MOF interfaces integrates the surface plasmon resonance excitation of Au nanorods with a Pt-MOF Schottky junction, which not only extends the light absorption of the MOF from the UV to the visible region but also greatly accelerates charge transfer. The spatial separation of Pt and Au particles by the MOF further steers the formation of charge flow and expedites the charge migration. As a result, the Pt@MOF/Au presents an exceptionally high photocatalytic H₂ production rate by water splitting under visible light irradiation, far superior to Pt/MOF/Au, MOF/Au and other counterparts with similar Pt or Au contents, highlighting the important role of each component and the Pt location in the catalyst.

Up the junction: A wide-band gap semiconductor-like metal–organic framework (MOF), MIL-125, with Pt nanoparticles in its crystal structure and Au nanorods on its outer surface gives Pt@MIL-125/Au, a catalyst with two metal–MOF interfaces. The integration of surface plasmon resonance (SPR) Au excitation with the Pt–MOF Schottky junction results in high photocatalytic H₂ production activity.