Materials Chemistry Frontiers最新文献

Environmental pollution from organic contaminants poses a significant threat to ecosystems and human health, which require innovative and efficient remediation strategies. Porphyrin-based materials, renowned for their excellent photochemical properties, have emerged as promising photocatalysts for degrading organic pollutants under light irradiation. Introducing porosity into these porphyrin systems further enhances their catalytic performance by improving pollutant adsorption, increasing surface area, and facilitating efficient light utilization. This review highlights recent progress in the design, synthesis, and functionalization of porous porphyrin-based photocatalysts, including metal–organic frameworks (MOFs), covalent organic frameworks (COFs), hydrogen-bonded organic frameworks (HOFs) and porous organic polymers (POPs). Particular attention is given to their applications in environmental remediation, such as the degradation of pharmaceuticals, pesticides, dyes, and industrial wastes. The underlying photocatalytic mechanisms, performance metrics, and real-world applicability are discussed in detail. Finally, the prospects and challenges of porous porphyrin-based materials for photocatalysis are also discussed.

Using a host–guest doping strategy to construct materials with excellent phosphorescence properties has important practical significance, and designing guests with strong luminescence properties to enhance the phosphorescence activity of doped systems is a commonly used method. However, enhancing phosphorescence performance through hosts is often overlooked. Herein, a doped system was constructed by selecting five compounds containing Group 15 elements (triphenylamine, triphenylphosphine, triphenylarsine, triphenylstibine, and triphenylbismuthine) as the hosts, and triphenylamine derivatives as the guests. The luminescence intensity of the doped materials is significantly enhanced by the external heavy atom effect of the hosts, and the phosphorescence quantum efficiency gradually increases from 5.2–5.6% in triphenylbismuthine-based doped materials to 22.8–26.0% in triphenylbismuth-based doped materials. Theoretical calculations show that heavy atoms significantly enhance the SOC of the hosts, thereby inducing an increase in the phosphorescence intensity of the doped materials. In addition, the single crystal structure and XRD analyses of the hosts further demonstrated that heavy atoms give the host a larger spatial volume and good deformability, allowing for better encapsulation of guest molecules. Finally, the doped materials can be effectively used for in vivo subcutaneous afterglow imaging in mice, demonstrating good imaging performance.

Organic room-temperature phosphorescent (RTP) materials are of increasing interest due to their unique triplet-state emission and potential applications in anti-counterfeiting, bioimaging, and optical storage. However, challenges such as low emission efficiency, short lifetimes, and limited scalability have hindered their practical use. Herein, we report a facile and scalable synthesis of difluoroboron β-diketonate (BF₂bdk) compounds and their incorporation into a poly(methyl methacrylate) (PMMA) matrix via emulsion polymerization. The rigid microenvironment of PMMA effectively suppresses non-radiative decay of the triplet state, yielding an RTP emulsion with a phosphorescence lifetime of up to 1.38 s. Blending with commercial emulsions enables the fabrication of uniform, transparent RTP coatings that can be obtained with bright afterglow exceeding 10 s. These coatings exhibit excellent environmental stability, thermal and chemical resistance, and industrial applicability. This study addresses the long-standing challenge of the scalable fabrication of aqueous afterglow materials, and offers a promising route for the large-scale production of high-performance organic RTP materials, paving the way for their integration into diverse application scenarios such as advanced optical and security technologies.

The development of efficient metal-free electrocatalysts for the oxygen reduction reaction (ORR) is essential for advancing sustainable energy technologies. In this work, we report the post-synthetic functionalization of covalent organic frameworks (COFs) with donor–acceptor (D–A) motifs incorporating thiophene and naphthalimide derivatives, yielding two novel materials. These COFs were synthesized via CuAAC click chemistry and thoroughly characterized. Electrochemical analyses revealed enhanced ORR activity in both materials, with one COF exhibiting near-ideal four-electron selectivity and remarkable stability. Density functional theory (DFT) calculations corroborated the experimental results, demonstrating that the electronic structure of COFs facilitates efficient O–O bond cleavage and electron transfer. These findings underscore the potential of rationally designed D–A COFs as high-performance, metal-free ORR electrocatalysts, contributing to the development of next-generation sustainable energy conversion technologies.

Conventional thermal sensors often face limitations due to their reliance on direct contact and restricted measurement ranges, leading to the emergence of novel techniques like luminescence thermometry. However, sensitivity of luminescent thermometers is limited by the only used Boltzmann-based Mott–Seitz model, which is imperfect. To overcome this, we complemented Mott–Seitz model applying machine learning algorithms, achieving supreme accuracy improvement. Thus, here we report a combined approach to luminescence thermometry, utilizing novel mixed-metal polymer Eu³⁺/Tb³⁺ tris-complex and a deep learning algorithm. The complex, synthesized using 4,4,4-trifluoro-1-(5,5-dimethyl-1H-pyrazol-4-yl)butane-1,3-dione, exhibits maximum relative thermal sensitivity of 5.5% K⁻¹ and a temperature uncertainty ranging from 0.1 to 1.8 K across a wide temperature range (190 to 300 K). We enhanced accuracy seven-fold from RMSE 2.54 K for the conventional intensity ratio method to RMSE 0.36 K for combined method using convolutional neural network. These results highlight the potential of combined approach to achieve record-high precision thermometers even for common compounds.

The rapid evolution of photovoltaic (PV) technology has made solar modules a key solution to meet growing global energy demands. In this context, achieving higher PV efficiency and reducing energy costs have become paramount objectives. Tandem solar cells, in which perovskite subcells are integrated with silicon (Si) subcells, represent a viable solution to surpass the Shockley–Queisser (S–Q) limit that constrains the efficiency of single-junction solar cells. These tandem configurations have demonstrated remarkable efficiency, reaching up to 34.85%, and are at the forefront of current PV research. This review focuses on recent studies aimed at enhancing the efficiency, stability, and scalability of tandem solar cells, including categorizing key areas of development in tandem solar cells into internal components (e.g., Si and perovskite subcells and interconnecting layers) and external components (e.g., encapsulation and busbars). Additionally, we address the fabrication process and levelized cost of energy (LCOE) of perovskite/Si tandem solar cells for cost-effective mass production. Moreover, we provide an outlook on the technological advancements required for the successful commercialization of tandem solar cells.

Hydrogen and n-butanol are emerging as clean energy carriers, necessitating reliable sensors for their low concentration detection. This study investigates an aluminium-doped CuO (CuO:Al) sensor coated with a zeolitic imidazolate framework-8 (ZIF-8) layer for hydrogen and n-butanol detection. Comprehensive characterization was performed using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), thermogravimetric analysis (TGA), N₂-adsorption isotherms, and Raman spectroscopy, collectively confirming a crystalline structure, intact chemical composition, beneficial surface morphology, uniform metal–organic framework (MOF) particle distribution, hierarchical porosity, and a high thermal stability of the synthesized materials. CuO promotes interaction with hydrogen and n-butanol, while the ZIF-8 coating enhances selectivity by mitigating the sensitivity to other gases and confers high immunity to elevated relative humidity (RH 81%) for hydrogen gas sensing. The hybrid MOF-ZIF-8/CuO:Al (ZIF-8 coated CuO:Al) sensor demonstrates remarkable thermal and temporal stability and maintains consistent performance even in humid conditions. Electrical activation energy (∼0.2 eV), corresponding to hole trap state (V_Cu), was calculated, confirming the p-type conduction mechanism. A gas sensing response of 400% was observed for 1000 ppm hydrogen gas under low relative humidity (RH 11%), remaining stable over four weeks. The gas sensing response remained at 300% even at a higher relative humidity (RH 50%) and sustained a response of 200% even after four weeks under the same RH. This shows its potential for hydrogen detection in industrial safety, environment monitoring, clinical medical diagnosis, and its reliable deployment in hydrogen generated energy applications.

Predicting the electronic band gap of nanomaterials is essential for discovering and developing novel nanostructures with tailored properties for a myriad of applications, including biomedical and pharmaceutical applications. Band gap predictions are commonly performed using computational modeling approaches such as molecular dynamics simulations and density functional theory calculations. However, the high computational cost and extensive infrastructural requirements of these methods have impeded their wider adoption and consequently, more rapid and efficient discovery of high-performance nanomaterials. In this contribution, we demonstrate the use of explainable ensemble supervised learning to accelerate the prediction of the electronic band gap of anisotropic nanomaterials. We systematically assess the capacity of several base models and a stacking model in predicting the band gap of more than 300 polyhedral nanomaterials with varying atomic-scale structural attributes. By coupling ensemble learning with explainable feature selection, we achieve outstanding performance in predicting nanomaterial band gap, with R² values above 0.96 and MSE below 0.004. We anticipate that this work can further catalyze the development of machine learning and other artificial intelligence approaches to streamline the prediction of the band gap and other electronic properties of nanomaterials.

Metal batteries are promising alternatives to present lithium-ion batteries, recognized for their good energy density and storage capacity, but they still suffer from significant safety and performance challenges. Advancements in safer, more stable electrolytes such as ionic, low volatility electrolytes offer a way to address these challenges. Here we report the first combination of a zwitterionic plastic crystal (ZPC) with different Na salts and compare the properties of these electrolytes with those formed from the first use of LiTFSI with a ZPC, for the development of safer, quasi-solid state and liquid electrolytes for lithium and sodium batteries. Thermal and structural analyses, using techniques such as DSC, EIS, IR spectroscopy and solid state and diffusion NMR, revealed that the conductivity and phase behaviour are highly dependent on the salt type and concentration. 50% NaTFSI–ZPC mixtures showed higher conductivity and transference numbers than equivalent LiTFSI–ZPC mixtures, while the 50% NaFSI–ZPC electrolyte enabled the best Na cycling despite a lower transference number. These findings underscore the potential of ZPCs for the development of efficient electrolytes for next-generation energy storage systems.

Dual-mode fluorescence-phosphorescence emission materials have attracted significant attention due to their wide range of potential applications. However, it remains challenging to obtain organic dual-mode fluorescence-phosphorescence materials that are both highly efficient and long-lived. To investigate the impact of molecular structures on fluorescent-phosphorescent temperature probes, phenanthrene (Phen) and teriphenylene (TP), two polycyclic aromatic hydrocarbons, were introduced into the phenoxathiin (POX) unit, which exhibits a folding-induced enhanced spin–orbit coupling effect. The POX derivatives (POXPhen and POXTP) were doped as guest emissive molecules into melamine-formaldehyde polymer films, showing both highly efficient fluorescence and phosphorescence with phosphorescence quantum yields and lifetimes exceeding 20% and 1 second, respectively. Theoretical and experimental results demonstrate that different steric hindrance effects and van der Waals forces exerted by the Phen and TP groups on the POX unit lead to perturbed conformations involving the torsion angles between Phen/TP groups and POX fragments. These perturbed conformations impact the intersystem crossing process as well as fluorescence and phosphorescence processes. Notably, the molecular conformational distribution exhibits temperature reliability, and the temperature-dependent emission of POXPhen and POXTP demonstrates a good linear relationship between the phosphorescence to fluorescence intensity ratio and temperature, ranging from 9.25 °C to 110.95 °C and 5.25 °C to 88.95 °C, respectively. These findings provide important theoretical guidance for the design of precise temperature probes gauging fluorescent-phosphorescent ratios by regulating perturbed molecular conformations.