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Metal-organic frameworks (MOFs) are distinguished by their unique porosity and meticulously ordered framework structures, setting them apart from conventional complexes. These materials are defined by their highly organized crystalline and pore structures, extensive surface areas, robust porosity, and superior adsorption capabilities. Owing to their exceptional structural and functional attributes, MOFs and their derivatives are leveraged across a broad spectrum of applications, demonstrating significant potential across diverse sectors. In recent times, the scientific community has increasingly focused on MOFs, underscoring their growing importance in research. Despite the promising array of applications for MOFs and their derivatives, challenges persist in practical deployments, and the pathway to research advancement remains daunting. This document delves into the synthesis and various applications of MOFs and their derivatives, particularly in the domains of energy storage, catalysis, sensing, and water treatment. It also highlights the ongoing research progress in the field of electrochemistry, including developments in lithium ion batteries (LIBs), lithium-sulfur batteries (LSBs), zinc-ion batteries (ZIBs), aqueous nickel-zinc batteries (NZBs), and supercapacitors. Finally, it provides an outlook on the future prospects and potential hurdles facing the development of MOF materials.

Large-area flexible organic photovoltaic (OPV) modules are challenging to achieve high power conversion efficiency (PCE). Electrical shunts or shortages generally occur in large-area OPV modules due to the ultrathin (100–200 nm) and soft active layers. Improving the surface smoothness of bottom transparent electrode will be able to suppress the shunts and shortages. In this work, we report a method to fabricate smooth and flexible transparent electrodes based on thin silver film, and further to fabricate efficient large-area flexible OPV modules. The fabricated thin silver transparent electrodes simultaneously have high conductivity, high optical transmittance, good mechanical flexibility and low surface roughness. Humidity exposure (h.e.) treatment on MoO₃ effectively facilitates the continuous growth of the thin transparent silver electrode. 6 nm silver film on MoO₃ (h.e.) on plastic substrate shows a transmittance up to 89%, a sheet resistance of 15 Ω/sq, and a low surface roughness with a root-mean-square value of 0.276 nm. Furthermore, 52-cm² flexible organic solar modules (15 subcells) showed a certified PCE of 12.66%. Furthermore, a 1350 cm² flexible component assembled by 25 pieces of 52–55 cm² modules showed certified PCE of 12.10% with an open-circuit voltage of 62.85 V.

Single-atom catalyst has garnered widespread attention to mimic mature enzymes due to its well-defined atomic structure and coordination environments. However, since the carbon-carbon (C–C) coupling reactions require synergistic catalysis of multiple sites, single-atom catalysts suffer from insufficient active sites and unclear reaction mechanisms. Controlling the reaction intermediates in a precisely targeted pocket through careful metal-organic cage design is therefore crucial. Here, we prepare a tetrahedral [Cu₆L₄]-type boron–imidazolate cage integrating highly active Cu sites and optimized cavity, which exhibits enzyme like specific catalytic performance in electrochemical CO₂ reduction reaction (CO₂RR) to enhance the selectivity of C₂H₄. Electrochemical analyses and computational calculations suggest that the single Cu site together with neighboring boron-imidazolate ligands provides suitably synergistic effects that enable the energetically favorable formation of an *COCHO intermediate, a key step determining selectivity. As a result, the [Cu₆L₄]-type cage of BIC-145 achieves a Faradaic efficiency of 28% for C₂H₄ maintaining an average current density of −3.54 mA cm⁻² over a 5-hour electrolysis period. This work represents the first example for studying single-metal site catalysts with ultra-low coordination numbers through the rational design of metal-organic cages.

Tunable light–matter interactions are exhibited by organic low-dimensional crystals, making these crystals a promising platform for organic photonics. However, the precise synthesis of organic low-dimensional crystals remains challenging due to the stochastic nature of molecular nucleation processes. Herein, the directed nucleation process is driven by the introduction of metastable seed-crystals as the trunk, which ultimately leads to branched-array organic heterostructures. The successful formation of organic heterostructures with high-density branched arrays is attributed to the highest attachment energy (E_att(023) = −104.25 kcal mol⁻¹) of the exposed (023) crystal plane during the seed-crystal growth route. Significantly, these as-prepared heterostructures inherently have an ultralow lattice mismatch ratio η of 0.7% between trunk and branch, which contributes to the multi-channel photon transportation. Therefore, this work provides valuable insights into a versatile synthetic strategy for accessing low-dimensional heterostructures for integrated optoelectronics.

Polyhedral boranes are a class of well-known boron molecular clusters widely used in energy, chemistry, medicine, and materials science because of their unique physical and chemical properties. Great efforts have been made in the past decades to find more effective synthetic methods for this important class of boron compounds. However, existing synthetic methods suffer from low efficiency and low selectivity. Herein, we report a facile one-pot synthesis of [(CH₃)₃S]₂B₁₂H₁₂ with moderate yields at mild conditions. The mechanisms for the multi-step chemoselective synthesis of B₁₂H₁₂²⁻ without other by-products are elucidated based on theoretical results and our previous work. The Lewis base used in B–H bond condensation reaction, which acts as a hydrogen or to balance the newly generated polyhedral borane charges, is proposed and studied in detail. The current study has led to a more effective and selective synthetic method for B₁₂H₁₂²⁻ and has also implicated the syntheses of other new polyhedral boranes.

Hypoxia is a significant feature in most of solid tumors. Hence, developing hypoxia-responsive phototheranostic system is still a challenge. In this contribution, a supramolecular assembly strategy based on sulfonate-functionalized azocalix[4]arene (SAC4A) and cationic aggregation-induced emission photosensitizer (namely TPA-H) was proposed for hypoxia-responsive bioimaging and photodynamic therapy (PDT). Upon supramolecular complexation of TPA-H and SAC4A through electrostatic interaction, the fluorescence and reactive oxygen species (ROS) generation of TPA-H were largely inhibited. In hypoxic tumors, the azo group of SAC4A can be reduced to aniline derivative and release the included TPA-H to recover its pristine fluorescence and ROS. Interestingly, the free TPA-H undergoes cell membrane-to-mitochondria translocation during cell imaging, achieving a real-time self-reporting PDT system. In vivo tumor imaging and therapy reveal that this as-prepared supramolecular complexes have good biosafety and efficient antitumor activity under hypoxia. Such hypoxia-responsive supramolecular photosensitizer system will enrich image-guided photodynamic therapy.

The development of an advanced phototheranostic platform that combines imaging and therapy in a single agent is an appealing yet challenging task. In this study, we successfully constructed three novel fluorescent probes by leveraging pharmaceutical chemistry and the design philosophy of the π-bridge effect. Through a systematic comparative analysis of their fluorescence properties, water solubility, molecular conformation, and electrostatic potential, we revealed the fundamental principles governing the optical behavior and biological selectivity of these probes. Notably, the probe TPhIQ-CNTh demonstrated extended fluorescence in the near-infrared region, a significant aggregation-induced emission (AIE) effect, and the ability to distinguish tumor cells from normal cells. Moreover, it efficiently generated reactive oxygen species (ROS) and specifically labeled lipid droplets, enabling the precise staining and killing of cancer cells. This study presents a practical strategy for designing precise tumor treatments that integrate efficient imaging-guided photodynamic therapy (PDT) by harnessing the unique properties of AIE materials.

This study concentrates on the development of high temperature polymer electrolyte membranes (HT-PEMs), which are essential components for HT-PEM fuel cells (HT-PEMFCs). Although the phosphoric acid (PA)-doped polybenzimidazole (PBI) has been regarded as the successful HT-PEM, this system still suffers from several challenges, including the use of carcinogenic monomers, complex synthesis procedures, and poor solubility in organic solvents. To develop more cost-effective, readily synthesized and high-performance alternatives, this study employs a simply superacid-catalyzed Friedel-Crafts reaction to synthesize a series of poly(triphenyl-co-dibenzo-18-crown-6 pyridine) copolymers, denoted as P(TP_x%-co-CE_y%), using p-triphenyl, dibenzo-18-crown-6 and 4-acetylpyridine as monomers. The copolymerized hydrophilic and bulky crown ether unites introduce large free volumes and multiple interaction sites with PA molecules, as elucidated by theoretical calculations. Meanwhile microphase separation structures are formed as confirmed by atomic force microscope (AFM), transmission electron microscopy (TEM) and small-angle X-ray scattering (SAXS). Thus P(TP_x%-co-CE_y%) membranes exhibit excellent PA absorption and proton conduction abilities. For example, after immersing in 85 wt% PA at 30 °C, the P(TP_91%-co-CE_9%) membrane achieves a PA doping content of 205% and a high conductivity of 0.138 S cm⁻¹ at 180 °C, while maintaining a tensile strength of 7.5 MPa at room temperature. Without humidification and backpressure, the peak power density of an H₂-O₂ cell equipped with P(TP_91%-co-CE_9%)/205%PA reaches nearly 1200 mW cm⁻², representing one of the highest performances reported for PA-doped HT-PEMs to date. This work demonstrates the enormous potential of poly(triphenyl-co-crown ether pyridine) membranes in the HT-PEMFC applications.

C-Alkyl glycosides are found in natural products and are indispensable in drug development programs, owing to their diverse range of medicinal properties. Two-component reactions involving glycosyl radical addition are well documented and proved efficient for the C-alkyl glycosides synthesis. However, multicomponent reactions for the rapid and controllable construction of structurally diversified C-alkyl glycosides in a single step remains a significant challenge due to the issues associated with balancing reactivity, compatibility, and selectivity. Herein, we report an NHC and photoredox co-catalyzed three-component method to access complex and valuable C-alkyl glycosides. This protocol exhibits broad substrate scope and excellent chemo- and regioselectivity. Furthermore, nine types of sugars are compatible with this reaction. In addition, the generality of this catalytic strategy was further highlighted by the potential for scalable production, the feasibility of further modifications of the products and its successful application in the late-stage functionalization of pharmaceutical skeletons.