Class Of Materials Research Articles

Application of Problem-Based Learning (PBL) Learning Model to Improve Student Learning Outcomes in Arithmetic Row Material Class XI SMAN 6 Southwest Aceh

Application of Problem-Based Learning (PBL) Learning Model to Improve Student Learning Outcomes in Arithmetic Row Material Class XI SMAN 6 Southwest Aceh

Zn-MOF as a saturable absorber for thulium/holmium-doped fiber laser

Metal–organic framework (MOF) is a class of material that is highly porous and modular. Due to their unique properties, MOFs have found applications in gas storage, gas separation, sensing, and supercapacitors. [Zn2(H2L)2(1,2-Bis(4-pyridyl)ethene)4]n, zinc (Zn)-based MOF was used in this work to achieve mode-locked operation in a thulium/holmium-doped fiber laser due to its excellent optical absorption at a wavelength of 1925 nm. The saturable absorber (SA) was fabricated by drop-casting a mixture of Zn-MOF and isopropanol on an arc-shaped fiber. The center wavelength of the mode-locked laser is 1906.75 nm, with a maximum average output power of 3.251 mW. The fundamental repetition rate and the pulse width were 12.89 MHz and 1.772 ps. At the same time, the pulse energy and peak power were 252 pJ and 142 W, respectively. To the authors’ knowledge, this is the first time an MOF has been used for mode-locked pulse generation in a thulium/holmium-doped all-fiber laser. This work extends the use of MOF material as a saturable absorber for mode-locking applications in near-infrared fiber lasers.

Additive Manufacturing of Tough Silicone Via Large-Scale, High-Viscosity Vat Photopolymerization

Abstract In this work, a large-scale, high-viscosity vat photopolymerization additive manufacturing system is designed and fabricated to print 3D structures as large as 370 × 300 × 370 mm3 out of high-viscosity, low-reactivity elastomeric resins. A detailed overview is presented of the printer's design and capabilities, including a resin processing sub-system that stores and spreads high-viscosity resin; a roll-to-roll variable tensioning system to mitigate the separation forces after printing each layer; and a light patterning system that generates high-intensity light patterns across an area of 370 × 300 mm2 with a resolution of 3840 × 4320 pixels. The ability to print with both high-viscosity and low-reactivity resins and resins that require high-intensity light enables additive manufacturing of new classes of materials that could not be printed previously using vat photopolymerization techniques. These materials include highly reinforced silica nanoparticle composites, high-molecular-weight polymers such as silicones and acrylate or methacrylate resins, and low-reactivity resins such as photocurable platinum-catalyzed liquid silicone rubber.

Mapping causal pathways with structural modes fingerprint for perovskite oxides

Abstract Causality is innate to determination of fundamental mechanism controlling any physical phenomena. However, combining causality within the standard practices of computational modeling to understand structure-functionality connections is extremely rare. This work proposes a fingerprint based on key structural modes for ABO3-type perovskite oxides and its derivatives, combined with causal models, for predicting Kohn-Sham energies. Our study of causal models capture the inherent coupling between structural modes such as rotation, tilt and antiferroelectric displacements, responsible for phase transition, polarization, magnetization and metal-insulator transition, exhibited by these materials. Although developed for modeling specific functionality, this method is universally applicable to derive other functionalities and even different material classes while tracking hidden causal mechanisms via structural distortions.

Facile Synthesis of a Layered Bismuth-Based MOF With Superhydrophobic-Oleophilic Property and High Oil-Water Separation Performance.

Metal organic frameworks (MOFs) are a class of potential superhydrophobic-oleophilic materials. The organic ligands in superhydrophobic MOFs usually contain long alkyl chains, fluorine groups or aromatic rings with large π conjugation, the preparation of which suffers from high cost, complex operation and so on. In addition, the topological structure of MOFs plays an important role in the hydrophobicity, which may be ignored previously. Here we report a superhydrophobic-oleophilic MOF (BiPPA2) obtained by a facile and fast method, which not only displays a large water contact angle of up to 163° and a small sliding angle of nearly equal to 0°, but also exhibits high sorption capacity for multiple oils and organic solvents, well reusability and high oil retention. In addition, BiPPA2 is stable in a wide pH range (0.5-11.0). Finally, the single crystal structure of BiPPA2 is resolved to reveal the intrinsic reason for the super-hydrophobicity. This work may inspire the further design of pristine superhydrophobic MOFs based on a simple method, which enriches the family of superhydrophobic MOFs and has great significance for practical applications.

Eulerian Formulation of the Constitutive Relation for an Electro-Magneto-Elastic Material Class

Eulerian Formulation of the Constitutive Relation for an Electro-Magneto-Elastic Material Class

Synthesis and application of a perfluorinated coumarin surfactant as an antifouling coating

Perfluorinated constitute a class of non-polluting antifouling materials. The perfluorinated surfactants have been studied and used in our laboratory for biological tests. The results have shown that they have an effect that is all the faster the higher their concentration. When they are combined with coumarins, their duration of action increases, become specific and exhibit extraordinary physicochemical properties namely, flexibility, elasticity, chemical inertia ....Field tests in the port of the city of Oran (Algeria) have confirmed that soluble matrix paints formulated with this hybrid (perfluorinated coumarins) as antifouling agents have succeeded in preventing the attachment of soiling organisms. With this in mind, our objective is to study in a comparative way the properties of this new material with those of the commercial Micron Extra EU. The composition of this surfactant used is determined by nuclear magnetic resonance (1H NMR), the aggregation characteristics and the glass transition temperature of the surfactant are evaluated by Differential Enthalpy Analysis (DSC).

The Molecular Nature of Redox-Conductive Metal-Organic Frameworks.

ConspectusRedox-conductive metal-organic frameworks (RC-MOFs) are a class of porous materials that exhibit electrical conductivity through a chain of self-exchange reactions between molecularly defined, neighboring redox-active units of differing oxidation states. To maintain electroneutrality, this electron hopping transport is coupled to the translocation of charge balancing counterions. Owing to the molecular nature of the redox active components, RC-MOFs have received increasing attention for potential applications in energy storage, electrocatalysis, reconfigurable electronics, etc. While our understanding of fundamental aspects that govern electron hopping transport in RC-MOFs has improved during the past decade, certain fundamental aspects such as questions that arise from the coupling between electron hopping and diffusion migration of charge balancing counterions are still not fully understood.In this Account, we summarize and discuss our group's efforts to answer some of these fundamental questions while also demonstrating the applicability of RC-MOFs in energy-related applications. First, we introduce general design strategies for RC-MOFs, fundamentals that govern their charge transport properties, and experimental diagnostics that allow for their identification. Selected examples with redox-active organic linkers or metallo-linkers are discussed to demonstrate how the molecular characteristics of the redox-active units inside RC-MOFs are retained. Second, we summarize experimental techniques that can be used to characterize charge transport properties in a RC-MOF. The apparent electron diffusion coefficient, Deapp, that is frequently determined in the field and obtained in large perturbation, transient experiments will be discussed and related to redox conductivity, σ, that is obtained in a steady state setup. It will be shown that both MOF-intrinsic (topology, pore size, and apertures) and experimental (nature of electrolyte, solvent) factors can have noticeable impact on electrical conductivity through RC-MOFs. Lastly, we summarize our progress in utilizing RC-MOFs as electrochromic materials, materials for harvesting minority carriers from illuminated semiconductors and within electrocatalysis. In the latter case, recent work on multivariate RC-MOFs in which redox active linkers are used to "wire" redox catalysts in the crystal interiors will be presented, offering opportunities to independently optimize charge transport and catalytic function.The ambition of this Account is to inspire the design of new RC-MOF systems, to aid their identification, to provide mechanistic insights into the governing ion-coupled electron hopping transport mode of conductivity, and ultimately to promote their applications in existing and emerging areas. With basically unlimited possibilities of molecular engineering tools, together with research in both fundamental and applied fields, we believe that RC-MOFs will attract even more attention in the future to unlock their full potential.

Ultrafast Interfacial Charge Transfer in Anisotropic One-Dimensional CsPbBr3/Pt Epitaxial Heterostructure.

Colloidal one-dimensional (1D) perovskite nanorods (NRs) and metal epitaxial heterostructures (HSs) are the promising class of new materials for efficient photovoltaic and photocatalytic applications. Besides, fundamental photophysical properties and its device applications of 1D perovskite-metal HSs are limited due to their challenging synthetic protocols and difficulties in forming epitaxial growth between covalent and ionic bonds. Herein, we have synthesized the CsPbBr3 perovskite NRs-platinum (Pt) nanoparticles (NPs) (CsPbBr3/Pt) epitaxial HS using cation exchange followed by chemical reduction methods with the orthorhombic Cs2CuBr4 NRs. Here, the tertiary ammonium ions extensively helped to form the 1D Cs2CuBr4, CsPbBr3 NRs, and CsPbBr3/Pt HSs. For CsPbBr3/Pt HSs an epitaxial relationship has been established in the (020) plane of orthorhombic CsPbBr3 with the (020) plane of cubic Pt. Further, femtosecond transient absorption (TA) spectroscopy was employed to study the charge carrier dynamics of CsPbBr3/Pt HS. Upon 420 nm photoexcitation, excitons in the conduction band of CsPbBr3 NRs dissociate by electron transfer (with an ultrafast time of 1.1 ps) to the Pt domain. In addition, charge transfer (CT) was also demonstrated in the CsPbBr3/Pt HS, which is ascribed to strong electron coupling and epitaxial growth between CsPbBr3 and Pt states. This extensive understanding of the electron transfer dynamics of CsPbBr3/Pt epitaxial HS may pave the way to designing highly efficient photovoltaic and photocatalytic applications.

Exploitation of Pore Structure for Increased CO2 Selectivity in Type 3 Porous Liquids.

CO2 capture requires materials with high adsorption selectivity and an industrial ease of implementation. To address these needs, a new class of porous materials was recently developed that combines the fluidity of solvents with the porosity of solids. Type 3 porous liquids (PLs) composed of solvents and metal-organic frameworks (MOFs) offer a promising alternative to current liquid carbon capture methods due to the inherent tunability of the nanoporous MOFs. However, the effects of MOF structural features and solvent properties on CO2-MOF interactions within PLs are not well understood. Herein experimental and computational data of CO2 gas adsorption isotherms were used to elucidate both solvent and pore structure influences on ZIF-based PLs. The roles of the pore structure including solvent size exclusion, structural environment, and MOF porosity on PL CO2 uptake were examined. A comparison of the pore structure and pore aperture was performed using ZIF-8, ZIF-L, and amorphous-ZIF-8. Adsorption experiments here have verified our previously proposed solvent size design principle for ZIF-based PLs (1.8× ZIF pore aperture). Furthermore, the CO2 adsorption isotherms of the ZIF-based PLs indicated that judicious selection of the pore environment allows for an increase in CO2 selectivity greater than expected from the individual PL components or their combination. This nonlinear increase in the CO2 selectivity is an emergent behavior resulting from the complex mixture of components specific to the ZIF-L + 2'-hydroxyacetophenone-based PL.

Interfacial deterioration in highly fluorinated cation-disordered rock-salt cathode: Carbonate-based electrolyte vs. ether-based electrolyte

Cation-disordered rock-salts (DRX) emerge as an intriguing class of high-capacity cathode materials, garnering significant attention in the development of advanced energy-storage systems. Fluorination strategies have been raised to regulate redox and structure for better DRX electrochemical performance. However, research on the interfacial processes during fluorinated DRX cycling remains limited. Here, we evaluate a highly fluorinated DRX, Li2Mn2/3Nb1/3O2F (LMNOF), in different electrolytes to correlate its cycling performance with distinct interfacial evolutions. During cycling in the carbonate-based electrolyte, a thick Mn-containing CEI forms on the LMNOF surface, leading to gradual capacity decay. Intriguingly, the addition of fluoroethylene carbonate (FEC) would bring about surface oxygen loss, Mn-ion dissolution and formation of a fluorinated surface layer by reacting with the LMNOF surface, which critically deteriorate the cycling performance. In comparison, the ether-based electrolyte is compatible with the LMNOF surface, resulting in a more favorable cycling stability. This work sheds light on the interfacial deterioration mechanism of LMNOF cathode in traditional carbonate-based electrolyte, emphasizing the importance of using advanced non-reactive electrolytes to enhance DRX performance.

A Recyclable Ionogel with High Mechanical Robustness Based on Covalent Adaptable Networks.

Ionogels are an emerging class of soft materials for flexible electronics, with high ionic conductivity, low volatility, and mechanical stretchability. Recyclable ionogels are recently developed to address the sustainability crisis of current electronics, through the introduction of non-covalent bonds. However, this strategy sacrifices mechanical robustness and chemical stability, severely diminishing the potential for practical application. Here, covalent adaptable networks (CANs) are incorporated into ionogels, where dynamic covalent crosslinks endow high strength (11.3MPa tensile strength), stretchability (2396% elongation at break), elasticity (energy loss coefficient of 0.055 at 100% strain), and durability (5000 cycles of 150% strain). The reversible nature of CANs allows the ionogel to be closed-loop recyclable for up to ten times. Additionally, the ionogel is toughened by physical crosslinks between conducting ions and polymer networks, breaking the common dilemma in enhancing mechanical properties and electrical conductivity. The ionogel demonstrates robust strain sensing performance under harsh mechanical treatments and is applied for reconfigurable multimodal sensing based on its recyclability. This study provides insights into improving the mechanical and electrical properties of ionogels toward functionally reliable and environmentally sustainable bioelectronics.

Domestic and Productive Earthen Architecture Conserved In Situ in Archaeological Sites of the Iberian Peninsula

For past societies on the Iberian Peninsula, one of the most prolific architectures was earthen construction, with a wealth of typologies and solutions derived from the legacy of local construction and materials. However, its study within the field of archaeology has been limited. The challenges posed by conservation, archaeological identification and social recognition have traditionally limited the dissemination of this type of architecture. Its low profile is perceived as fragile once the original protections collapse. The ethnological information preserved and linked to past ways of life and societies is crucial to the interpretation of the cultural development handed down over generations by different communities and now transmitted to the general public through archaeological sites. This research aims to provide an overview of the main earthen vestiges from domestic, productive and funerary architecture dating from the prehistoric, protohistoric, Roman and medieval periods. For this, a bibliographical review and data collection through fieldwork were conducted for numerous case studies. These included the classification of materials, compositions and construction techniques, creating an integrated comprehensive database with information on geography, measurements and the general state of conservation.

Synthesis, technological prospects and applications of MXene in biomedicine, supercapacitors and sensors: A review

MXenes are one of the most important classes of materials discussed worldwide by many researchers of diverse fields for diverse applications in recent years. It is a nanomaterial with a wide range of applications due to its multiple forms and structures with fascinating properties, for example, high surface area and porosity, biocompatibility, ease of fictionalizing with various active chemical moieties, benefit of high metallic conductivity, activated metallic hydroxide sites, and sensitivity to moisture. MXenes have great chances for potential applications in environmental issues, water purification, biological applications, and energy storage devices and sensors. MXenes show great selectivity towards the absorption of heavy metals and a good capability to reduce chemical and biological pollutants present in the water. The present review article critically analyzed advancements in water purification using the adsorption and reduction abilities of MXenes and their composites. The mechanism of various procedures, important challenges, and associated problems using MXene and their composites are discussed in detail. The future research directions can be extracted from this article efficiently and comprehensively. The energy storage issues of rechargeable lithium-ion batteries, batteries other than lithium-ion batteries, and electrochemical capacitors are also discussed in detail.

First-principles study of optoelectronic and thermoelectric aspects of novel zintl phase SrAg2X2 (X = S, Se, Te) alloys for green energy applications

This work comprehensively investigates the solar energy harvesting and thermoelectric capabilities of innovative Zintl phase SrAg2X2 (X = S, Se, Te) alloys. Herein, the analysis of the structural, optoelectronic, and thermoelectric characteristics of Zintl SrAg2X2 (X = S, Se, Te) compounds has been conducted utilizing the WIEN2k code. The formation energy has been evaluated to elaborate the thermodynamic stability of Zintl compounds. The materials demonstrate characteristics of semiconductors, with anticipated band gap values of 1.78 eV for SrAg2S2, 1.63 eV for SrAg2Se2, and 1.50 eV for SrAg2Te2. The optical characteristics have been examined to assess the potential use of these phases in optoelectronic and photovoltaic systems. The standard Boltzmann transport theory has been used to analyze thermoelectric parameters concerning temperature and chemical potential. Thermoelectric features have also verified the p-type characteristics of these semiconductors. Considerably higher predicted values of the power factor and higher figure of merit demonstrate the capability of thermal energy conversion. Consequently, these outstanding optoelectronic and thermoelectric aspects values indicate that this class of materials may be highly suitable for use in solar and thermoelectric systems.

Metamaterial enhanced sensor for powder material classification

In this paper, a simple and efficient approach is presented to classify different power materials based on a one port microwave sensor in X-band. This classification focuses on powder materials, unlike prior studies that focused on liquids (castor oil, neem oil, sunflower oil, sesame oil, and mahua oil), this classification represents a shift towards powdered materials. The response of the proposed sensor is enhanced by adding a metamaterial (MTM) unit cell of F-shape to focus electromagnetic waves on the sample under test. This metamaterial-based sensor is designed to differentiate between different types of materials based on the corresponding reflection coefficient. The sample under test is included inside a dielectric box inserted inside a rectangular waveguide. The MTM unit cell is added on the front face of this box towards the direction of the incident wave. The resonance frequency depends on the characteristics of the powder material inside the box. The MTM unit cell enhances this resonance to simplify the process of classification of different materials. The measured results show that the proposed sensor can detect a wide range of powder materials, including clay, cement, sand, and mixtures: cement & sand, and clay & sand. The designed sensor can be used in various applications, including detection and classification of different powder materials in industrial applications.

Ferroelectric/Piezoelectric Materials in Energy Harvesting: Physical Properties and Current Status of Applications

The inevitable feedback between the environmental and energy crisis within the next decades can probably trigger and/or promote a global imbalance in both financial and public health terms. To handle this difficult situation, in the last decades, many different classes of materials have been recruited to assist in the management, production, and storage of so-called clean energy. Probably, ferromagnets, superconductors and ferroelectric/piezoelectric materials stand at the frontline of applications that relate to clean energy. For instance, ferromagnets are usually employed in wind turbines, superconductors are commonly used in storage facilities and ferroelectric/piezoelectric materials are employed for the harvesting of stray energy from the ambient environment. In this work, we focus on the wide family of ferroelectric/piezoelectric materials, reviewing their physical properties in close connection to their application in the field of clean energy. Among other compounds, we focus on the archetypal compound Pb(Zr,Ti)O3 (or PZT), which is well studied and thus preferred for its reliable performance in applications. Also, we pay special attention to the advanced ferroelectric relaxor compound (1−x)Pb(Mg1/3Nb2/3)O3−xPbTiO3 (or PMN-xPT) due to its superior performance. The inhomogeneous composition that many kinds of such materials exhibit at the so-called morphotropic phase boundary is reviewed in connection to possible advantages that it may bring when applications are considered.

In-vivo toxicological study of cysteamine modified carbon dots derived from Ruellia simplex on fruit fly for potential bioimaging

Modern medicine must shift its paradigm from conventional treatment strategies to theranostics to meet individuals' needs. Carbon dots, as a class of fluorescent materials, provide biocompatible and multifunctional solutions for a wide range of applications including clinical sensing, imaging, and drug delivery. Various studies have focused on their synthesis, photophysical properties, and innoxious nature but their potential biomedical applications for the in-vivo toxicity are yet limited. In this work, previously synthesized C-Dots (CDs) were utilized to determine their effect on the development of Drosophila melanogaster. Simultaneously, the genotoxic potential of CDs was evaluated on specific larval cell types that play important roles in immunological defence as well as growth and development. The gut organ toxicity of both CDs was studied using DAPI and DCFH-DA dyes wherein RS-CDs didn't show significant toxicity to the concentration 500 μg/mL whereas RS-Cys-CDs showed nuclear fragmentation and modest ROS (reactive oxygen species) production. Subsequently, trypan-blue assay, larvae crawling assay, touch sensitivity, adult phenotype, and survivability assay were performed. The trypan-blue assay shows the non-toxic nature of both CDs even at the concentration of 500 μg/mL. The high concentrations of RS-Cys-CD (500 μg/mL) were further associated with the alteration in touch behaviour and decrease in pupa hatching. In-vivo and ex-vivo fluorescence assessment of both the CDs exhibit bright fluorescence in green and red channels upon excitation at 485 and 577 nm respectively. The prominent imaging results from RS-Cys-CDs highlight the positive impact of surface modification.

The research progress on COF solid-state electrolytes for lithium batteries.

Lithium metal batteries have garnered significant attention due to their high energy density and broad application prospects. However, the practical use of traditional liquid electrolytes is constrained by safety and stability challenges. In the exploration of novel electrolytes, solid-state electrolyte materials have emerged as a focal point. Covalent organic frameworks (COFs), with their large conjugated structures and unique electronic properties, are gradually gaining attention as an emerging class of solid-state electrolyte materials. In recent years, outstanding electrochemical performance has been achieved through the design and synthesis of various types of COF-based solid-state electrolytes, along with successful integration with other functional materials. This review will provide an overview of the research progress on COFs as solid-state electrolyte materials for lithium metal batteries and offer insights into their future potential in battery technology.

Interplay between disorder and electronic correlations in compositionally complex alloys

Owing to their exceptional mechanical, electronic, and phononic transport properties, compositionally complex alloys, including high-entropy alloys, represent an important class of materials. However, the interplay between chemical disorder and electronic correlations, and its influence on electronic structure-derived properties, remains largely unexplored. This is addressed for the archetypal CrMnFeCoNi alloy using resonant and valence band photoemission spectroscopy, electrical resistivity, and optical conductivity measurements, complemented by linear response calculations based on density functional theory. Utilizing dynamical mean-field theory, correlation signatures and damping in the spectra are identified, highlighting the significance of many-body effects, particularly in states distant from the Fermi edge. Electronic transport remains dominated by disorder and potentially short-range order, especially at low temperatures, while visible-spectrum optical conductivity and high-temperature transport are influenced by short quasiparticle lifetimes. These findings improve our understanding of element-specific electronic correlations in compositionally complex alloys and facilitate the development of advanced materials with tailored electronic properties.