Advanced Functional Materials Research Articles

Efficient Synthesis of Metastable Cyclodextrin-Based Polyrotaxanes with Tunable Threading Ratios.

Cyclodextrin-based polyrotaxanes (CD-PRs) are gaining attention for their dynamic sliding rings along the polymer axis, enabling various applications in molecular shuttles, drug delivery, and durable polymers with slidable cross-links. However, the conventional synthesis of CD-PRs with tunable threading ratios is typically laborious, time-consuming, and complicated, which limits their scalability and cost-effectiveness. Herein, we highlight the great potential of planetary centrifugal mixing, a process that significantly accelerates and simplifies the initial synthesis of polypseudorotaxanes (PPRs), followed by a thiol-ene click reaction as an efficient end-capping reaction for the synthesis of PRs. Notably, PRs synthesized with glutathione (GSH) as the end-capping reagent are in a metastable state, where GSH act as a molecular bumper that significantly prevent de-threading of α-CD rings at room temperature. Moreover, the rate of ring de-threading can be precisely controlled by heating, enabling the preparation of metastable PRs with tunable threading ratios over a wide range. The developed strategy is of great significance to the efficient synthesis of CD-PRs, thus marking a significant step towards their practical application in advanced functional materials and devices.

Efficient Synthesis of Metastable Cyclodextrin‐Based Polyrotaxanes with Tunable Threading Ratios

Cyclodextrin‐based polyrotaxanes (CD‐PRs) are gaining attention for their dynamic sliding rings along the polymer axis, enabling various applications in molecular shuttles, drug delivery, and durable polymers with slidable cross‐links. However, the conventional synthesis of CD‐PRs with tunable threading ratios is typically laborious, time‐consuming, and complicated, which limits their scalability and cost‐effectiveness. Herein, we highlight the great potential of planetary centrifugal mixing, a process that significantly accelerates and simplifies the initial synthesis of polypseudorotaxanes (PPRs), followed by a thiol‐ene click reaction as an efficient end‐capping reaction for the synthesis of PRs. Notably, PRs synthesized with glutathione (GSH) as the end‐capping reagent are in a metastable state, where GSH act as a molecular bumper that significantly prevent de‐threading of α‐CD rings at room temperature. Moreover, the rate of ring de‐threading can be precisely controlled by heating, enabling the preparation of metastable PRs with tunable threading ratios over a wide range. The developed strategy is of great significance to the efficient synthesis of CD‐PRs, thus marking a significant step towards their practical application in advanced functional materials and devices.

Characterizations and Energy Analysis of Hydroxyl Group Functionalized Graphene (Nanomaterial) Mixed with Paraffin Wax (Polymer Pcm) as Thermal Energy Storage Materials And Applications

This work comprised of Paraffin wax as phase change material mixed/doped with functionalized graphene (hydroxyl group) for countering the poor thermal conductivity of the pristine phase change material. Firstly, Experiments were conducted on Thermal energy storage system during charging (melting) of the doped PCM. The main outcomes of these experiments were that as the volume concentrations of doped PCM and flow rate of the heat transfer fluid (HTF) were increased the charging time decreases along with increments in PCM temperature and accumulated energies. In case of OH functionalized graphene mixed with paraffin wax the charging time decreases by 38.4% to 84.61% for the HTF flow rate 25 ml/s over pure paraffin wax. Secondly, the advanced functional materials i.e., Paraffin wax mixed with functionalized hydroxyl group graphene was characterized by FTIR, XRD, TGA, DSC and FESEM, . The latent heat of melting obtained was 179.36 J/g for 1% graphene doping by DSC.

Isoreticular Metal-Organic Framework-3 (IRMOF-3): From Experimental Preparation, Functionalized Modification to Practical Applications.

Isoreticular metal-organic framework-3 (IRMOF-3), a porous coordination polymer, is an MOF material with the characteristics of a large specific surface area and adjustable pore size. Due to the existence of the active amino group (-NH2) on the organic ligand, IRMOF-3 has more extensive research and application potential. Herein, the main preparation methods of IRMOF-3 in existing research were compared and discussed first. Second, we classified and summarized the functionalization modification of IRMOF-3 based on different reaction mechanisms. In addition, the expanded research and progress of IRMOF-3 and their derivatives in catalysis, hydrogen storage, material adsorption and separation, carrier materials, and fluorescence detection were discussed from an application perspective. Moreover, the industrialization prospect of IRMOF-3 and the pressing problems in its practical application were analyzed and prospected. This review is expected to provide a reference for the design and application of more new nanomaterials based on IRMOF-3 to develop more advanced functional materials in industrial production and engineering applications.

Advanced functional materials as reliable tools for capturing food-derived peptides to optimize the peptidomics pre-treatment enrichment workflow.

Peptidomics strategies with high throughput, sensitivity, and reproducibility are key tools for comprehensively analyzing peptide composition and potential functional activities in foods. Nevertheless, complex signal interference, limited ionization efficiency, and low abundance have impeded food-derived peptides' progress in food detection and analysis. As a result, novel functional materials have been born at the right moment that could eliminate interference and perform efficient enrichment. Of note, few studies have focused on developing peptide enrichment materials for food sample analysis. This work summarizes the development of endogenous peptide, phosphopeptide, and glycopeptide enrichment utilizing materials that have been employed extensively recently: organic framework materials, carbon-based nanomaterials, bio-based materials, magnetic materials, and molecularly imprinted polymers. It focuses on the limitations, potential solutions, and future prospects for application in food peptidomics of various advanced functional materials. The size-exclusion effect of adjustable aperture and the modification of magnetic material enhanced the sensitivity and selectivity of endogenous peptide enrichment and aided in streamlining the enrichment process and cutting down on enrichment time. Not only that, the immobilization of metal ions such as Ti4+ and Nb5+ enhanced the capture of phosphopeptides, and the introduction of hydrophilic groups such as arginine, L-cysteine, and glutathione into bio-based materials effectively optimized the hydrophilic enrichment of glycopeptides. Although a portion of the carefully constructed functional materials currently only exhibit promising applications in the field of peptide enrichment for analytical chemistry, there is reason to believe that they will further advance the field of food peptidomics through improved pre-treatment steps.

Experimental investigation of Aluminum Nitride ceramics based on compliant finishing process

Aluminum Nitride (AlN), as a type of advanced functional ceramic material, has found wide applications in many fields, owing to its advantageous properties such as excellent thermal conductivity, high hardness and strength, etc. Nevertheless, these beneficial features bring great challenges to its machinability using current existing methods that commonly result in unsatisfactory surface qualities. In this paper, we investigated the processing performance of AlN by introducing the compliant bonnet finishing approach based on different tool bonding materials and abrasive sizes. The distinctive finishing qualities, material removal rates, tool wear behavior, etc., were studied and compared under various process conditions. Unlike other ceramics, resin bonded diamond tools with a 3 μm abrasive size exhibit significant wear when used on AlN ceramics. The curves for tool wear amount and wear rate are investigated. Meanwhile, compliant tool with the smaller abrasive can obtain the sub-50 nm surface roughness. The comparison with traditional rigid pellet finishing further demonstrates the advantageous finishing performances by using compliant tools on the AlN ceramics.

Inducible biosynthesis of bacterial cellulose in recombinant Enterobacter sp. FY-07

Bacterial cellulose (BC) is an extracellular polysaccharide with myriad unique properties, such as high purity, water-holding capacity and biocompatibility, making it attractive in materials science. However, genetic engineering techniques for BC-producing microorganisms are rare. Herein, the electroporation-based gene transformation and the λ Red-mediated gene knockout method with a nearly 100 % recombination efficiency were established in the fast-growing and BC hyperproducer Enterobacter sp. FY-07. This genetic manipulation toolkit was validated by inactivating the protein subunit BcsA in the cellulose synthase complex. Subsequently, the inducible BC-producing strains from glycerol were constructed through inducible expression of the key gene fbp in the gluconeogenesis pathway, which recovered >80 % of the BC production. Finally, the BC properties analysis results indicated that the induced-synthesized BC pellicles were looser, more porous and reduced crystallinity, which could further broaden the application prospects of BC. To our best knowledge, this is the first attempt to construct the completely inducible BC-producing strains. Our work paves the way for increasing BC productivity by metabolic engineering and broadens the available fabrication methods for BC-based advanced functional materials.

Liquid-Liquid Phase Separation Mediated Formation of Chiral 2D Crystalline Nanosheets of a Co-Assembled System.

The role of macromolecule-macromolecule and macromolecule-H2O interactions and the resulting perturbation of the H-bonded network of H2O in the liquid-liquid phase separation (LLPS) process of biopolymers are well-known. However, the potential of the hydrated state of supramolecular structures (non-covalent analogs of macromolecules) of synthetic molecules is not widely recognized for playing a similar role in the LLPS process. Herein, LLPS occurred during the co-assembly of hydrated supramolecular vesicles (bolaamphiphile, BA1) with a net positive charge (zeta potential, ζ = +60 ± 2mV) and a dianionic chiral molecule (disodium l-[+]-tartrate) is reported. As inferred from cryo-transmission electron microscopy (TEM), the LLPS-formed droplets serve as the nucleation precursors, dictating the structure and properties of the co-assembly. The co-assembled structure formed by LLPS effectively integrates the counter anion's asymmetry, resulting in the formation of ultrathin free-standing, chiral 2D crystalline sheets. The significance of the hydrated state of supramolecular structures in influencing LLPS is unraveled through studies extended to a less hydrated supramolecular structure of a comparable system (BA2). The role of LLPS in modulating the hydrophobic interaction in water paves the way for the creation of advanced functional materials in an aqueous environment.

Lignin-based covalent organic polymers for highly efficient uranium extraction under highly acidic conditions

Uranium is the main actinide highly related with recycling fission fuel. In this study, we controllably construct a lignin-based covalent organic polymers (AO-EHL), for uranium extraction with high adsorption capacity (94.70 mg/g). The balanced adsorption efficiency for uranium is remarkably high under highly acidic conditions, and even maintains 99.99 % in pH = 1.0. Moreover, the high adaptability, excellent reusability, and extremely low operating costs further indicated the high feasibility of AO-EHL for uranium extraction in industrial scale. The excellent adsorption performance of AO-EHL for uranium is reasonably attributed to synthetic effects of amidoxime groups and the covalent structure of lignin, which can highly prevent the protonation of amidoxime groups, and thus showing strong complexation with uranium at high acidities. This study suggests a promising method to construct advanced functional materials by using cheap and green natural materials and realizing the efficient uranium extraction under highly acidic conditions.

Transition‐Metal‐Free Annulation of Sulfonyl‐Derived 1,3‐Enynes: Simple and Efficient Construction of 2,4‐Disubstituted Thiophenes and Vinyl Sulfone‐Tethered 1,2,3‐NH‐Triazoles

AbstractThiophenes and 1,2,3‐NH‐triazoles are important frameworks in pharmaceuticals and advanced functional materials. Vinyl sulfones are also blueprint motifs in medicinal chemistry, but hybrid analogues of 1,2,3‐NH‐triazole‐derived from vinyl sulfones still need to be explored. In this report, we present an efficient and transition‐metal‐free [4+1]‐thioannulation of sulfonyl‐tethered 1,3‐enynes with Na2S in the presence of Cs2CO3 to generate 2,4‐disubstituted thiophenes in good to high yields. We also established a formal [3+2]‐cycloaddition of 1,3‐sulfonylenynes with NaN3 under metal‐ and base‐free conditions to synthesize vinyl sulfone‐containing 1,2,3‐NH‐triazole derivatives in moderate to high yields. The scope of these protocols was successfully showcased with various types of 1,3‐enynes bearing sensitive functional groups and complex structural scaffolds. The desired products were readily obtained with good functional group tolerance and compatibility. Based on the existing results and control experiments, plausible mechanistic pathways are also presented.

Jellyfish-Inspired Self-Healing Luminescent Elastomers Based on Borate Nanoassemblies for Dual-Model Encryption.

Responsive luminescent materials that reversibly react to external stimuli have emerged as prospective platforms for information encryption applications. Despite brilliant achievements, the existing fluorescent materials usually have low information density and experience inevitable information loss when subjected to mechanical damage. Here, inspired by the hierarchical nanostructure of fluorescent proteins in jellyfish, we propose a self-healable, photoresponsive luminescent elastomer based on dynamic interface-anchored borate nanoassemblies for smart dual-model encryption. The rigid cyclodextrin molecule restricts the movement of the guest fluorescent molecules, enabling long room-temperature phosphorescence (0.37 s) and excitation wavelength-responsive fluorescence. The building of reversible interfacial bonding between nanoassemblies and polymer matrix together with their nanoconfinement effect endows the nanocomposites with excellent mechanical performances (tensile strength of 15.8 MPa) and superior mechanical and functional recovery capacities after damage. Such supramolecular nanoassemblies with dynamic nanoconfinement and interfaces enable simultaneous material functionalization and self-healing, paving the way for the development of advanced functional materials.

Vanadium pentoxide nanowires preparation via kinetic control of vanadium oxytrichloride catalytic oxidation with APCVD

Vanadium pentoxide nanowires were successfully fabricated using vanadium oxytrichloride oxidation with copper oxide nanoparticles serving as catalysts via atmospheric pressure chemical vapor deposition. Kinetic parameters such as temperature and flow velocity were proved to play important roles in the morphologic control of as-deposited product. Vanadium pentoxide nanowires with an average length of ∼10 μm and a diameter of 50–100 nm, were obtained under the optimum conditions. A root growth mechanism of nanowires was proposed that precursor was readily captured by catalyst nanoparticles at the beginning of deposition, forming nucleation sites. Subsequently, the anisotropic growth of vanadium pentoxide is primarily governed by energy minimization under the reaction rate limited conditions. The presence of oxygen vacancies in the nanowires was confirmed by Raman, XPS and photoluminescence characterization, indicating promising applications in functional materials manufacture. The novel route for preparing vanadium pentoxide nanowires provides an alternative pathway for transitioning traditional vanadium industry towards advanced functional materials development.

Editorial: Recent advances in functional materials: polymers and composite materials

Editorial: Recent advances in functional materials: polymers and composite materials

Concise synthesis of 2,4-bis(fluoroalkyl)quinoline derivatives from arylamines

Quinolines and their derivatives bearing fluorine-containing substituents are essential structural motifs found in numerous bioactive compounds and advanced functional materials. Therefore, there is an urgent need to develop new synthetic methods for fluoroalkylated quinoline derivatives. In this study, we present a facile and efficient approach to access fluoroalkylated quinoline derivatives by using Eaton's reagent as a cost-effective, and commercially available reagent. This Combes cyclization reaction demonstrated compatibility with various arylamines bearing diverse functional groups, resulting in the synthesis of 2,4-bis(trifluoromethyl)quinolines and 2,4-bis(difluoromethyl)quinolines in moderate to high yields. Furthermore, this reaction can be conveniently carried out in a solvent-free one-pot protocol.

Engineering Light‐Driven Rod‐Shaped Micromotors for Exhibiting Controlled and Tunable Multimode Swimming

AbstractThe recent era of research has been focused on attaining precise and adjustable propulsion modes in micromotors, with remarkable implications in microrobotics and active‐matter applications. This study introduces a novel design of rod‐shaped micromotors featuring light‐driven motion and wavelength‐dependent multimodal swimming behavior. The micromotors are fabricated through the Glancing Angle Deposition (GLAD) technique, which offers a flexible approach to engineering surfaces by incorporating photocatalytic materials (TiO2 and Cu2O) at specific locations. Here, three distinct designs of micromotors (titania, hybrid‐1, and hybrid‐2) are presented that are programmed to showcase diverse behaviors of movements (linear, helical, and axial rotation) when exposed to a specific wavelength. The application of light facilitates convenient control over activity and mode switching by altering between UV and visible ranges. Numerical modeling using a finite element approach is performed to validate the experimental results, demonstrating excellent agreement with the experimental findings. The present study is anticipated to be helpful in tailoring such complex micro/nanoscale advanced functional materials with intricating swimming modes desired for various applications in micro/nanorobotics.

Green conversion of carbon disulfide to degradable polydithiourethanes through catalyst-free multicomponent polymerizations of diamines, carbon disulfide and diacrylates

In the pursuit of advanced functional polymer materials, sulfur-containing polymers have received tremendous attention owing to their superior chemical stability, high refractive indices, various supramolecular interactions, and robust dynamic covalent chemistry. However, their synthesis usually involves either expensive monomers or toxic byproducts and requires catalysts, thus hindering their widespread application. In this work, we present a catalyst-free multicomponent polymerization in organic solvents for the synthesis of various polydithiourethanes with excellent yields (up to 98 %) and high molecular weights (up to 112 kg/mol). This reaction involves the direct polymerization of carbon disulfide, an abundant one-carbon feedstock, with commercially available diamines and diacrylates. This polyaddition process demonstrates high atom economy and no byproduct, occurring at room temperature without the need for a catalyst, thus exhibiting excellent green chemistry metrics. By utilizing the dynamic covalent chemistry of dithiourethane groups, these polymers can be efficiently degraded via aminolysis and used to fabricate reprocessable vitrimers. This multicomponent polymerization opens up a new avenue for the efficient utilization of carbon disulfide resources and accelerates the exploration of diversified sulfur-containing functional polymer materials.

Auto‐Pressurized Multi‐Stage Tesla‐Valve Type Microreactors in Carbon Monoliths Obtained Through 3D Printing: Impact of Design on Fluid Dynamics and Catalytic Activity

AbstractThe present research exploits an innovative methodology for producing auto‐pressurized carbon microreactors with a precise and controlled structure analyzing the influence of their design on the fluid dynamics and their catalytic performance. Carbon monoliths with Tesla‐valve shape channels (Tesla, T, and modified Tesla, Tm) are synthesized through the combination of 3D printing and sol–gel process and further probed as Ni/CeO2 supports on CO2 methanation. The experimental results and mathematical modeling corroborated the improved performance obtained through the complex design compared to a conventional one. In addition to chaotic fluid flow induced by the deviation in flow direction, which improves the reagents‐active phase interaction, local pressure increases due to convergence of flows may enhance the Sabatier reaction according to Le Châtelier's principle. Conversely to straight channels, T and Tm are not affected by flow rate and presented chemical control. Tesla‐valve with curved angle (Tm) improved the mass transfer, achieving higher conversion and ≈30% reaction rate increase regarding right angle (T). Thus, this auto‐pressurized multi‐stage Tesla‐valve monolith opens the gate to design specific and advanced functional materials for multitude chemical reactions where not only the reactant‐active phase contact can be maximized but also the reaction conditions can be controlled to maximize the reaction kinetics.

Chemical short-range disorder in lithium oxide cathodes.

Ordered layered structures serve as essential components in lithium (Li)-ion cathodes1-3. However, on charging, the inherently delicate Li-deficient frameworks become vulnerable to lattice strain and structural and/or chemo-mechanical degradation, resulting in rapid capacity deterioration and thus short battery life2,4. Here we report an approach that addresses these issues using the integration of chemical short-range disorder (CSRD) into oxide cathodes, which involves the localized distribution of elements in a crystalline lattice over spatial dimensions, spanning a few nearest-neighbour spacings. This is guided by fundamental principles of structural chemistry and achieved through an improved ceramic synthesis process. To demonstrate its viability, we showcase how the introduction of CSRD substantially affects the crystal structure of layered Li cobalt oxide cathodes. This is manifested in the transition metal environment and its interactions with oxygen, effectively preventing detrimental sliding of crystal slabs and structural deterioration during Li removal. Meanwhile, it affects the electronic structure, leading to improved electronic conductivity. These attributes are highly beneficial for Li-ion storage capabilities, markedly improving cycle life and rate capability. Moreover, we find that CSRD can be introduced in additional layered oxide materials through improved chemical co-doping, further illustrating its potential to enhance structural and electrochemical stability. These findings open up new avenues for the design of oxide cathodes, offering insights into the effects of CSRD on the crystal and electronic structure of advanced functional materials.

Controllable preparation and formation mechanism of highly ordered hydroxyapatite nanofibers: Effect of PO43−/CO32-

Hydroxyapatite (HAP), as an inorganic material with the biocompatible and bioactive, widely exists in hard tissues such as teeth and bones of mammals. However, the inherent brittleness of traditional HAP severely limits its clinical applications in load-bearing. HAP ultralong nanofibers with good flexibility can overcome this problem due to their high aspect ratio. In this work, the highly ordered HAP nanofibers are successfully synthesized by the calcium oleate precursor solvothermal method. The effects of ratio of PO43− and CO32− on the microstructure, orientation degree, and properties are researched. The results show that the arrangement of HAP nanofibers first changes from loose state to ordered dense structure, then to ordered loose form, and finally to disordered nanofibers with the increase of the PO43−/CO32− ratio. Meanwhile, the chemical composition, crystallinity, and thermal stability also change because of various PO43−/CO32−. In addition, the formation mechanism of highly ordered HAP nanofibers is explored as well in this work. Besides, the HAP ultralong nanofibers prepared by solvothermal method can be designed into advanced functional materials with highly ordered structures, which is expected to overcome the limitation of its difficult application in the load-bearing field.

Effect of Mn (as an acceptor) on the structural and electrical properties of non-stoichiometry Sodium Bismuth Titanate/NBT ceramics

The lead free Na0.5Bi0.5TiO3 (NBT) ceramic is proven as a potential piezoelectric candidate; however, non-stoichiometry NBT serves as an outstanding oxide-ion conductor proposed by (M. Li et al., Nature Materials 13 (2014) 31–35). According to this point here we have systematically report the structural and electrical properties of non-stoichiometry Na0.5Bi0.49TiO3/NB0.49T and B-site Mn3+ acceptor-modified NB0.49T system. Therefore, we are trying to prepare the nominal formula of Na0.5Bi0.49Ti1-xMnxO3; NB0.49T ceramic with 0.0≤x ≤ 0.05 by solid state reaction method. The bulk oxide ion conductivity gradually increases with respect to the doping concentration and the maximum value was obtained for x = 0.05 composition. This conductivity maximum is in good consistent with R. A. De Souza's oxygen vacancy diffusivity limit concept for perovskite systems (Advanced Functional Materials, 25 (2015)). On doping of 5mol% of Mn in the Ti-site/B-site NB0.49T system, it was observed that the oxygen-ion conduction inside the grain boundary increased considerably. Grain conductivity of NaBi0.49TiO3 at 500 °C is ∼3.0 ± 0.5 mS cm−1, which is approximately 122 % greater than that pure NBT compositions. Additionally, NB0.9T -exhibited a conductivity value of 4.7 mS/cm at 500 °C, which increases to 9.2 mS/cm on 5 mol% Mn-modification. The observed increase in conductivity was ascribed due to the electrostatic interactions between Mn–Ti or Mn–O bond. Therefore, our current findings on NB0.49T illustrates that present approach should be applicable to modify the system for SOFC application.