Design strategies, advanced functionalities and emerging application of donor-acceptor porphyrin based covalent organic frameworks

Covalent organic frameworks (COFs) are crystalline porous polymers with modular architectures and long-range order, offering exceptional tunability in pore structure and functionality. While conventional COFs are typically constructed from one or two types of monomers, recent advances have led to the emergence of multicomponent COFs (MC-COFs), which integrate three or more distinct building blocks within a single lattice. This strategy enables the precise spatial arrangement of diverse geometries, connectivity, and functionalities, imparting synergistic complexity beyond the reach of single- or binary-component systems. In this perspective, we present a comprehensive overview of MC-COF chemistry, organised around five representative construction strategies: isostructural and heterostructural copolymerization, multicomponent topological design, multicomponent reactions, and pore partitioning strategies. We further highlight how these frameworks enable emergent functions in catalysis, alkane isomer separation, chemical sensing, and radiotherapy through rational control of both periodic backbone structure and local chemical environments. Despite these advances, challenges persist in structural characterization, expanding the scope of dynamic linkages, and achieving predictive design of emergent properties. Looking forward, the integration of dynamic covalent chemistry, topological programming, and machine learning-driven design is expected to unlock the full potential of MC-COFs as next-generation multifunctional materials.

ConspectusMetal-organic frameworks (MOFs) and covalent organic frameworks (COFs), as emerging porous crystalline materials, have attracted remarkable attention in chemistry, physics, and materials science. MOFs are constructed by metal clusters (or ions) and organic linkers through coordination bonds, while COFs are prepared by pure organic building blocks via covalent bonds. Because of the nature of linkages, MOFs and COFs have their own shortcomings. Typically, the relatively weak bond strengths of coordination bonds lead to poor chemical stability of MOFs, which limits their practical implementations. On the other hand, due to the strong covalent bonds, COFs exhibit rather higher stability under harsh conditions, compared to MOFs. However, the lack of open metal sites restricts their functionalization and application. Therefore, it is hypothesized that the "cream-skimming" of MOFs and COFs would address these drawbacks and produce a new class of crystalline porous material, namely, covalent metal-organic frameworks (CMOFs), with unprecedented structural complexity and advanced functionality. The CMOFs reveal a new synthetic approach for the preparation of reticular materials. Specifically, metal ions are reacted with chelating ligands to assemble metal complexes or clusters with functional reactive sites (e.g., -CHO, and -NH2), which can be further connected with organic linkers to form networked structures via dynamic covalent chemistry (DCC). The isolated metal complex or cluster precursors show enhanced stability which prevents structural decomposition and rearrangements during the self-assembly process of CMOFs. Since the topology of preassembled metal nodes is well-defined, the CMOFs structure can be readily predicted upon directed networking of covalent bonds. Unaccessible reticular materials from unstable or highly reactive metal ion/clusters under traditional conditions can be prepared via the DCC approach. Moreover, CMOFs synergize the advantages of MOFs and COFs, containing metal active sites ensuring various interesting properties, and covalent linkages that allow rather high chemical stability even under harsh conditions. In the past few years, our group has specifically focused on the development of general synthetic strategies for CMOFs by networking coinage metal (Cu, Ag, and Au)-based cyclic trinuclear units (CTUs) with DCC. The CTUs exhibit trigonal planar structures and can be functionalized with reactive sites, such as -NH2 and -CHO, that can further react with organic linkers to afford CMOFs. Notably, CTUs also features interesting properties including metallophilic attraction, π-acidity/basicity, luminescence, redox activity and catalytic activity, which can be incorporated into CMOFs. Therefore, we envision that CMOFs would be promising platforms not only for the development of novel reticular materials, but also for potential applications in many research fields including gas absorption/separation, sensing, full-color display, catalysis, energy, and biological applications. In this Account, we summarize the recent studies on CMOFs, starting with linkage and topological design, structural transformation, morphological control, and potential applications in various fields. We also discuss the future opportunities and challenges in this rapidly developed research field of CMOFs. We hope this Account may promote new scientific discoveries and further development of CMOF-based materials and technologies in the future.

Separators have evolved from passive polymeric barriers into multifunctional components that critically govern the performance, safety, and lifetime of liquid and quasi-solid lithium rechargeable batteries. This Review provides a comprehensive analysis of separator materials and architectures spanning commercial polyolefins and their ceramic coatings, high‑temperature polymers (PI, PEEK), nanofiber and bio‑derived membranes, and cross-linked gel/polymer-ceramic composites for quasi-solid systems. Design principles linking pore size, porosity, tortuosity, wettability, and Li+ transference to ionic conductivity and rate capability are systematically discussed, alongside mechanical and thermal requirements such as puncture resistance, dimensional stability, shutdown behavior, and flame retardance. We compare major fabrication routes-including dry and wet stretching, phase inversion, electrospinning, ceramic/oxide coating, UV/thermal crosslinking, and vacuum filtration/solution casting-and relate their process windows to separator microstructure, electrochemical performance, and scalability. Separator-electrolyte-anode interactions are analyzed with emphasis on dendrite suppression, flux homogenization, and interface stabilization in lithium‑metal and quasi‑solid cells. Finally, market and techno‑economic trends are summarized, highlighting the trade‑offs between advanced functionality and roll‑to‑roll manufacturability, as well as emerging directions toward intelligent (advanced) separators and PFAS‑free, recyclable architectures. This review outlines quantitative targets and design strategies needed to translate next‑generation separator concepts into safe, high‑energy, and commercially viable lithium battery technologies.

Advances in Emerging Crystalline Porous Materials.

Precise organization of matter across multiple length scales is of particular interest because of its great potential with advanced functions and properties. Here we demonstrate a simple yet versatile strategy that enables the organization of hydrophobic nanoparticles within the covalent organic framework (COF) in an emulsion droplet. The interfacial polymerization takes place upon the addition of Lewis acid in the aqueous phase, which allows the formation of COF after a crystallization process. Meanwhile, the interaction between nanoparticles and COF is realized by the use of amine-aldehyde reactions in the nearest loci of the nanoparticles. Importantly, the competition between the nanoparticle self-assembly and interfacial polymerization allows control over the spatial distribution of nanoparticles within COF. As a general strategy, a wide variety of COF-wrapped nanoparticle assemblies can be synthesized and these hybridized nanomaterials could find applications in optoelectronics, heterogeneous catalysis and energy chemistry.

Covalent organic frameworks (COFs) are periodic porous polymers with relatively high crystallinity, which have become a newly emerging family of materials. The COF materials are constructed by covalent bonds (B–O, C–C, C–N etc.) of light elements, and by using various organic building blocks we can create versatile COFs with diverse topology and functionalities. The COFs often possess the characteristics of low density, high porosity and large specific surface area, and have therefore been widely applied in gas adsorption and separation, energy chemistry and the environmental fields. To develop COF materials with appreciable functionalities, extensive experimental and theoretical techniques are being employed. In particular, multiscale simulation methods have been proven to be an efficient tool to design and investigate the properties of new COFs. This article mainly introduces two rational strategies to design new COF materials. One is linker replacement or the node replacement strategy to achieve high performance gas storage COF materials with large surface areas and pore volumes. The other is functional group modification or the metal doping strategy to design functionalized COFs with strong affinity towards gases. For the two design strategies, we also give a corresponding example for further analysis. Finally, we summarize the applications of COFs in hydrogen and methane storage, as well as CO2 capture.

Rational design, structure properties, and synthesis strategies of dual-pore covalent organic frameworks (COFs) for potent applications: A review

In this study we present the combination of a math-based design strategy with direct laser writing as high-precision technology for promoting solid free-form fabrication of multi-scale biomimetic surfaces. Results show a remarkable control of surface topography and wettability properties. Different examples of surfaces inspired on the lotus leaf, which to our knowledge are obtained for the first time following a computer-aided design with this degree of precision, are presented. Design and manufacturing strategies towards microfluidic systems whose fluid driving capabilities are obtained just by promoting a design-controlled wettability of their surfaces, are also discussed and illustrated by means of conceptual proofs. According to our experience, the synergies between the presented computer-aided design strategy and the capabilities of direct laser writing, supported by innovative writing strategies to promote final size while maintaining high precision, constitute a relevant step forward towards materials and devices with design-controlled multi-scale and micro-structured surfaces for advanced functionalities. To our knowledge, the surface geometry of the lotus leaf, which has relevant industrial applications thanks to its hydrophobic and self-cleaning behavior, has not yet been adequately modeled and manufactured in an additive way with the degree of precision that we present here.

Recent advancements in soft robotics have led to the development of compliant robots that can exhibit complex motions driven by living cells, chemical reactions, or electronics. Further innovations are, however, needed to create the next generation of soft robots that can carry out advanced functions and exhibit complex locomotion. Material designs that incorporate “smart” functional properties can contribute to the development of robotic systems with in‐built mechanical responsiveness and functions. Herein, a simple material design that integrates stimuli‐responsive self‐healing and microarchitectural features to control locomotion of soft robots is reported. By employing these material designs along with hyperelastic soft actuators to control propellant dispersion and direction, a circuitry of pneumatic and microfluidic logic is created within a dragonfly‐shaped body that enables the robot to undergo user‐ and environment‐controlled locomotion over water surface. In addition to steering the robot to skim, the material properties are also leveraged to detect water acidification, temperature changes, and hydrophobic impurities such as oil. The design, fabrication, and integration strategies demonstrated herein pave a way for developing futuristic multifunctional soft robots, biomedical devices, and environmental monitoring probe.

Application of covalent organic frameworks as electrode materials for supercapacitors

Covalent organic frameworks (COFs) have emerged as a unique class of crystalline porous materials assembled from light elements via dynamic covalent linkages, offering exceptional tunability, stability, and functionality. Among various COF linkages, azine-linked COFs, derived from Schiff-base condensation between aldehydes and hydrazine derivatives, have gained significant consideration owing to their enhanced chemical robustness, π-conjugation, and hydrolytic stability compared to conventional imine-based COFs. Additionally, azine linked COFs possess well-ordered pore structure, high porosity, good crystallinity, large accessible surface area, and tunable pore chemistry. These attributes make them promising candidates for various applications such as CO2 capture, hydrogen evolution, organic transformations, and removal of pollutants or ions even at high temperatures. This review highlights the recent advancements in the design strategies, synthetic methods, and structural features of azine-linked COFs, along with their emerging applications in CO2 capture, hydrogen evolution, organic transformations, and pollutant degradation. In addition, a brief overview of general COF linkages and synthetic approaches is provided to establish a broader context. Finally, current limitations and future perspectives are investigated to guide the continued development of Schiff-base-derived azine linkage COFs as versatile platforms for sustainable functional materials.

Diabetes mellitus is a worldwide leading disease that brings about fatal complications due to poor body glucose management which requires regular screening. With progressive evolution of healthcare monitoring system, high demand for wearable biosensors has efficiently bridged the gap between organic semiconductor devices and biological systems due to their flexibility and biocompatibility as enzyme-based transducing mechanism. In this work, significant features of existing glucose monitoring systems and integration components are evaluated to extend the fully integrated sensing platform with exciting potentials of organic thin-film transistor (OTFT) as electrochemical glucose sensor at low manufacturing process <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$&lt; 200 ^{\circ }\text{C}$ </tex-math></inline-formula> . This review highlights the design strategies and challenges in developing printable OTFT devices with low voltage and high on/off-current ratio <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$&gt; 10^{6}$ </tex-math></inline-formula> by considering material configuration including nanomaterials, advanced printing techniques and functionalization for highly sensitive performance based on amperometric or potentiometric measurements. For sample extraction, the role of microneedle is critically discussed with their prospects to provide real-time diagnosis of interstitial fluid through correlation with blood glucose for long wear period. It can be concluded that this paper accentuates the potentials of printable OTFT biosensors and ISF sampling system based on microneedle by adapting the key design requirements and characteristics presented here for novel breakthrough of cost-effective, minimally invasive and self-monitoring flexible integrated glucose sensor system that conform to skin.

Metal-organic frameworks (MOFs) and covalent organic frameworks (COFs) are recently notable examples of highly porous polymer frameworks with a raft of potential applications. Synthesis of these compounds is modular, with "connectors" and "linkers" able to be replaced almost at will in the fabrication of isoreticular frameworks (frameworks with the same underlying topology). The range of components available to form such framework structures is vast, leading to a "combinatorial explosion" problem in predicting which framework compounds might have a set of desired properties. Computational investigations can be used in both predictive and explanatory roles in this research but rely on accurate structural models. In this work, we present our software, AuToGraFS, Automated Topological Generator for Framework Structures, and show some of its advanced functionality in "computational reticular chemistry". AuToGraFS is linked to a fully featured force field to produce fully optimized structures of arbitrary frameworks. AuToGraFS, including a graphical user interface, is publicly available for download.

Advances in COFs for energy storage devices: Harnessing the potential of covalent organic framework materials

Covalent organic frameworks (COFs) have emerged as an interesting class of crystalline porous materials with desirable properties (such as highly ordered porosity, structural versatility, high chemical and thermal stabilities, and facile surface modification) and a broad range of potential applications. This critical review is aimed at providing insight into design strategies and synthetic methodologies for COFs. Unlike previous reviews on COFs, this article also focuses on the characterization of COFs, which is important for understanding the physical and chemical properties of COFs that are essential for practical applications. Furthermore, this review highlights the applications of COFs in various fields, including catalysis, photovoltaic devices, sensors, supercapacitors, wastewater treatment, biomedicine, chromatographic and spectroscopic analyses, and gas separation and storage. Lastly, perspectives on future directions and challenges associated with COFs are provided.