Hasil untuk "Materials Science"

Mohammad Nur-E Alam

This article presents a reflective survey of research contributions that are related to functional thin film materials, photovoltaic-related architectures, and energy-oriented applications. By synthesising findings from multiple investigations focused on semiconductors, metal-oxide composite systems, nanostructured coatings, and building relevant constituents, the work concentrates on proceeding of fabrication strategies as well as structure-property interrelationships and application-driven performance metrics. Rather than giving a full review of the literature, the article combines some of the experimental observations to highlight recurrent themes such as process optimisation, interface engineering, and multifunctional material behaviour. Particular emphasis is placed on the modulation of optical, electrical, and functional performance by modest variations in deposition conditions, dopant incorporation strategies, and structural design. A cross-there theme analysis shows practical feasibility, long-term stability, and scalability as important as peak performance in determining the suitability of advanced materials for energy applications. Unlike conventional component-focused reviews, this perspective articulates a translational design logic linking materials processing decisions directly to device reliability and system-level energy performance, providing a conceptual framework for accelerating lab-to-field deployment of sustainable energy technologies. The purpose is to highlight cross-cutting translational challenges and design principles that link functional materials to device- and system-level deployment, with particular relevance to real-world and remote-environment energy applications.

Lili Sun, Yong Yuan, Yang Xu et al.

Abstract Long-range exciton transport in organic semiconductors is essential for the performance of optoelectronic devices. However, solution-processed π-conjugated polymers films typically exhibit short exciton diffusion lengths (<20 nm) due to local imperfections or variations in interchain packing. Here, large-area submillimeter-scale spherulites are achieved by treating the spin-coated polydiarylfluorene film under solvent vapor annealing. The exciton diffusion length, visualized using transient photoluminescence microscopy, is determined to be an average of 186 nm, with a corresponding diffusion coefficient of 0.14 cm2 s-1. Notably, the maximum value of exciton diffusion lengths and diffusion coefficient can reach up to approximately 396 nm and 0.63 cm2 s-1, respectively. Well-ordered hierarchical structure with an outstanding chain alignment in spherulite provides a uniform excitonic energy landscape, enabling ultralong exciton diffusion. The reduced defect density in the spherulite film may result in shallower trap states, facilitating exciton diffusion and radiative recombination. Polymer light-emitting diodes based on submillimeter-scale spherulite films exhibit deep-blue electroluminescence with high brightness (4897 cd m-2) at low current density and good color purity. These findings demonstrate that the long-range ordered spherulite structure can significantly enhance the excitons transport and improve the overall optoelectronic property.

Hyejin Choe, Heesung Yoon, Inhyang Kim et al.

Halide perovskites have attracted significant interest due to their potential in optoelectronic devices. However, challenges related to complex compositional spaces, environmental sensitivity, and stability limitations continue to constrain their systematic development and application. Machine learning (ML) has emerged as an effective tool to address these challenges by enabling the prediction of material properties, the identification of promising compositions, and optimization of processing conditions, while reducing reliance on conventional trial‐and‐error methods. By capturing complex, nonlinear relationships among compositional, structural, and processing parameters, ML enables the exploration of broad design spaces that are essential for advancing perovskite research. Additionally, ML accelerates the discovery and optimization of perovskite materials through data‐driven approaches, including high‐throughput screening and inverse design, enabling rapid identification of optimal compositions and processing conditions for enhanced device performance and stability. This review provides an overview of recent efforts to integrate ML into halide perovskite studies, discussing workflows, implementation strategies, and notable progress in device‐level development. This article highlights how ML enables systematic materials discovery and optimization, supporting the advancement of stable and efficient perovskite optoelectronic devices.

Noor S. Sadeq, Siti Norain Harun, Gan Yian Chee et al.

Metal–Organic Frameworks (MOFs) have rapidly emerged as versatile nanoparticles system for their use in biomedical field, especially in drug delivery. Of the materials in this class, zeolitic imidazolate framework ZIF-8 has recently captured significant interest due to its tunable structure and significant potential for surface modification. It is these same features which allow ZIF-8 to act as a suitable carrier in both single agent and combination therapy. In particular, surface chemistry will be reiterated throughout the present article as significant in improving the physicochemical stability, biocompatibility and targeted drug delivery of the materials. In addition, through well-designed modification strategies ZIF-8 herein we propose to show controlled release profiles, improved colloidal stability, and improved therapeutic efficacy. This review will discuss recent advances made in the surface engineering of ZIF-8 and present salient design principles and functionalisation techniques and their usefulness in the area of drug-delivery applications.

Ru Wu, Yue Cao, Zixuan Chen et al.

Graphene quantum dots (GQDs), as an emerging class of nascent carbon-based materials, demonstrate remarkable promise in fluorescence sensing applications. Those potentials stem from several factors, including their favorable photoluminescence (PL) characteristics, feasibility of surface functionalization, excellent biocompatibility, and low cytotoxicity. This review concentrates on the fundamental optical properties of GQDs, with specific reference to the manipulation of intrinsic characteristics both by heteroatom doping and surface/edge functionalization. These modifications permit the alteration of optical properties, thereby rendering GQDs more versatile for an array of applications. Subsequently, we then delve into the recent applications of GQDs in fluorescence sensing, encompassing both turn-off and turn-on mechanisms. Finally, it presents a systematic assessment of the current state of research on GQDs, along with discussions on challenges and prospects for expanding and improving their applications.

Łukasz Rakoczy, Małgorzata Grudzień-Rakoczy, Grzegorz Cempura et al.

Abstract In this study, Ni-based superalloy Alloy 718 + xTiB2 (x = 1.25; 2.5; 3.75; 5.0%) composites were fabricated by suction casting to improve hardness, wear resistance, and corrosion resistance. The microstructure and properties were analyzed using synchrotron X-ray diffraction, light microscopy, scanning electron microscopy, scanning transmission electron microscopy, dilatometry, differential scanning calorimetry, Vickers hardness, wear resistance measurements, and corrosion tests. The results show that the addition of TiB2 to Alloy 718 has a strong influence on the primary microstructure. All composites are characterized by a dendritic microstructure with irregular distribution of strengthening precipitates. In the reference Alloy 718, the dendritic regions consist of the γ-phase, while interdendritic areas contain Nb-rich carbides and Laves phase precipitates. The TiB2 particles added to a powder mixture reacts strongly with the liquid Alloy 718 during suction casting, resulting in the decrease of the Laves phase and the formation of the M3B2 and M23B6 phases. Increasing the initial TiB2 content shifted the phase transformation temperatures (solidus and liquidus) to lower temperatures. Hardness values increased significantly from 198 HV10 in the reference Alloy 718 to 403 HV10 (5.0% TiB2), which contributed to improved wear resistance. Finally, high temperature exposures in rich oxygen atmosphere (steam) and reduced oxygen atmosphere (Ar + 0.25 vol% SO2) at 704 °C for 1000 h indicated that the Alloy 718 + TiB2 composites were characterized by a lower mass gain than the reference Alloy 718.

Piyush Kumar Soni, Amit Tiwari, S. N. V. J. Devi Kosuru et al.

Abstract This research presents a wide mathematical framework for modeling, developing, and optimizing the pressure vessels in hydrogen storage tanks using state-of-the-art solid materials. The emphasis is on metal hybrid storage tanks because these systems have been extensively studied from an experimental and theoretical perspective in the literature, and if the current R&D efforts are successful in bringing the required technology to market, they should offer several advantages. It is found that better cooling is essential during the hydrogen filling process of the storage tank in order to shorten the time required for hydrogen storage. CoMoCrSi + Cr2C3 material comprised the inner layer of the pressure vessel, while Inconel 713 made up the exterior layer. Their thicknesses were 10 mm and 8 mm, respectively. The pressure vessel’s response to various conditions could be assessed through static structural analysis in Ansys Workbench. This particular study aimed at investigating whether a square sample had met the requirements of storing hydrogen gas. Promising results indicate that the multi-layered design used for the pressure vessel is well-suited for hydrogen storage. This may be deduced from its ability to withstand pressure and maintain structural integrity, and this exceeds what other cylinder materials can do. Through sophisticated modeling tools and advanced materials science, this project demonstrates how improvements in hydrogen storage technology can contribute to sustainable energy development.

Bosen Zou, Ho Ming Ng, Zhengkai Li et al.

Abstract Indoor organic photovoltaics (IOPVs) are an emerging LED light recycling technology with promising applications such as indoor off‐grid ecosystem for the Internet of Things. However, efficient and stable IOPVs based on giant dimeric acceptors (GDAs) are rarely reported due to the dearth of GDAs with hypsochromic absorption (absorption onset < 850 nm) and good crystallinity. Herein, two hypsochromic GDAs are proposed with different fluorination degrees, namely DY4FO‐V and DY6FO‐V, and process a systematic study of hypsochromic acceptor materials from the small molecule to dimers and polymer. Interestingly, both hypsochromic GDAs possess better crystallinity, thus faster carrier transport and suppress recombination than small‐molecule and polymer acceptor‐based devices. With extra fluorination, PM6:DY6FO‐V exhibits higher external quantum efficiency response and tighter packing compared with PM6:DY4FO‐V. As a result, PM6:DY6FO‐V delivers a champion efficiency over 29% under a LED illumination of 2000 lux (2600 k), positioning it the highest values for GDA‐based IOPVs. Meanwhile, the high glass transition temperature of DY6FO‐V endowed corresponding devices with great photostability and enhanced mechanical stability in flexible devices, demonstrating the feasibility of practical applications of the DY6FO‐V‐based IOPVs. This research underscores the huge potential of developing hypsochromic GDAs for highly efficient IOPVs with superior stability.

Panpan Wu, Yueying Chu, Maoling Wang et al.

Abstract Direct photocatalytic oxidation of methane to high-value-added oxygenated products remains a great challenge due to the unavoidable overoxidation of target products. Here, we report an efficient and highly selective TiO2 photocatalyst anchored with subnanometric MoOx clusters for photocatalytic methane oxidation to organic oxygenates by oxygen. A high organic oxygenates yield of 3.8 mmol/g with nearly 100% selectivity was achieved after 2 h of light irradiation, resulting in a 13.3% apparent quantum yield at 365 nm. Mechanistic studies reveal a photocatalytic cycle for methane oxidation on the MoOx anchored TiO2, which not only largely inhibits the formation of hydroxyl and superoxide radicals and the overoxidation of oxygenate products but also facilitates the activation of the first carbon-hydrogen bond of methane. This work would promote the rational design of efficient non-noble metal catalysts for direct conversion of methane to high-value-added oxygenates.

Binrui Xu, Yong Liu, Bo Zhao et al.

Electrolyte additive engineering is a crucial method for enhancing the performance of aqueous zinc—ion batteries (AZIBs). Recently, most research predominantly focuses on the role of functional groups in regulating electrolytes, often overlooking the impact of molecule stereoscopic configuration. Herein, two isomeric sugar alcohols, mannitol and sorbitol, are employed as electrolyte additives to investigate the impact of the stereoscopic configuration of additives on the ZnSO₄ electrolyte. Experimental analysis and theoretical calculations reveal that the primary factor for improving Zn anode performance is the regulation of the solvation sheath by these additives. Among the isomers, mannitol exhibits stronger binding energies with Zn²⁺ ions and water molecules due to its more suitable stereoscopic configuration. These enhanced bindings allow mannitol to coordinate with Zn²⁺, contributing to solvation structure formation and reducing the active H₂O molecules in the bulk electrolyte, resulting in suppressed parasitic reactions and inhibited dendritic growth. As a result, the zinc electrodes in mannitol—modified electrolyte exhibit excellent cycling stability of 1600 h at 1 mA cm⁻² and 900 h at 10 mA cm⁻², respectively. Hence, this study provides novel insights into the importance of suitable stereoscopic molecule configurations in the design of electrolyte additives for highly reversible and high—rate Zn anodes.

Victoria Effiong Effanga, Dana Akilbekova, Fariza Mukasheva et al.

Osteochondral (OC) tissue plays a crucial role due to its ability to connect bone and cartilage tissues. To address the complexity of structure and functionality at the bone–cartilage interface, relevant to the presence of the tidemark as a critical element at the bone–cartilage boundary, we fabricated graded scaffolds through sequential 3D printing. The scaffold’s bottom layer was based on a gelatin/oxidized alginate mixture enriched with hydroxyapatite (HAp) to create a rougher surface and larger pores to promote osteogenesis. In contrast, the upper layer was engineered to have smaller pores and aimed to promote cartilage tissue formation and mimic the physical properties of the cartilage. An electrospun ε-polycaprolactone (PCL) membrane with micrometer-range pores was incorporated between the layers to replicate the function of tidemark—a barrier to prevent vascularization of cartilage from subchondral bone tissue. In vitro cell studies confirmed the viability of the cells on the layers of the scaffolds and the ability of PCL mesh to prevent cellular migration. The fabricated scaffolds were thoroughly characterized, and their mechanical properties were compared to native OC tissue, demonstrating suitability for OC tissue engineering and graft modeling. The distance of gradient of mineral concentration was found to be 151 µm for grafts and the native OC interface.

Ahmed S Alkarani

Introduction: Coronavirus Disease-2019 (COVID-19) has affected nursing staff and students mentally and physically due to their role in the frontline fighting the virus. However, data on the effect of COVID-19 on nursing students are limited and there have been no studies about Saudi nursing intern experience during this crisis. Aim: To explore the impact of COVID-19 pandemic on nursing students during their interns at hospitals and how they dealt with the COVID-19 pandemic. Materials and Methods: A qualitative descriptive study was done where 12 interviews were conducted among nursing student at the Nursing Department in the College of Applied Medical Science at Taif University, Taif, Saudi Arabia. The study was conducted from 1st January 2021 to 10th April 2021. The descriptive method was used to collect, understand, organise and represent in depth data. All the nursing student participants were interns and started their intern programmes during the COVID-19 pandemic. All interviews were auto-recorded, transcribed and analysed using a thematic method. Results: The four themes which emerged from findings were: student plans during COVID-19; students’ perspectives of the nursing profession; intern students’ mental states; and hospital roles. Conclusion: While the virus may negatively affect the experience of nursing intern students, the support of the media and society towards nursing staff during the pandemic has encouraged them significantly. So this study recommended that nursing stakeholders collaborate with the media to create greater interaction and embrace the nursing profession for younger generations.

Sirui Liu, Sirui Liu, Haojie Fu et al.

This study aimed to examine the effects of loading different concentrations of metformin onto an α-hemihydrate calcium sulfate/nano-hydroxyapatite (α-CSH/nHA) composite. The material characteristics, biocompatibility, and bone formation were compared as functions of the metformin concentration. X-ray diffraction results indicated that the metformin loading had little influence on the phase composition of the composite. The hemolytic potential of the composite was found to be low, and a CCK-8 assay revealed only weak cytotoxicity. However, the metformin-loaded composite was found to enhance the osteogenic ability of MC3T3-E1 cells, as revealed by alkaline phosphate and alizarin red staining, real-time PCR, and western blotting, and the optimal amount was 500 µM. RNA sequencing results also showed that the composite material increased the expression of osteogenic-related genes. Cranial bone lacks muscle tissue, and the low blood supply leads to poor bone regeneration. As most mammalian cranial and maxillofacial bones are membranous and of similar embryonic origin, the rat cranial defect model has become an ideal animal model for in vivo experiments in bone tissue engineering. Thus, we introduced a rat cranial defect with a diameter of 5 mm as an experimental defect model. Micro-computed tomography, hematoxylin and eosin staining, Masson staining, and immunohistochemical staining were used to determine the effectiveness of the composite as a scaffold in a rat skull defect model. The composite material loaded with 500 µM of metformin had the strongest osteoinduction ability under these conditions. These results are promising for the development of new methods for repairing craniofacial bone defects.

Xilong Zhao, Kangming Ren, Xinhong Lu et al.

Ultrasonic impact treatment (UIT) is carried out on the Ni-based alloy stainless steel pipe gas tungsten arc welding (GTAW) girth weld, the differences of microstructure, microhardness and shear strength distribution of the joint before and after ultrasonic shock are studied by microhardness test and shear punch test. The results show that after UIT, the plastic deformation layer is formed on the outside surface of the Ni-based alloy overlayer, single-phase austenite and γ type precipitates are formed in the overlayer, and a large number of columnar crystals are formed on the bottom side of the overlayer. The average microhardness of the overlayer increased from 221 H V to 254 H V by 14.9%, the shear strength increased from 696 MPa to 882 MPa with an increase of 26.7% and the transverse average residual stress decreased from 102.71 MPa (tensile stress) to −18.33 MPa (compressive stress), the longitudinal average residual stress decreased from 114.87 MPa (tensile stress) to −84.64 MPa (compressive stress). The fracture surface has been appeared obvious shear lip marks and a few dimples. The element migrates at the fusion boundary between the Ni-based alloy overlayer and the austenitic stainless steel joint, which is leaded to form a local martensite zone and appear hot cracks. The welded joint is cooled by FA solidification mode, which is forming a large number of late and skeleton ferrite phase with an average microhardness of 190 H V and no obvious change in shear strength. The base metal is all austenitic phase with an average microhardness of 206 H V and shear strength of 696 MPa.

Perosanz Sergio, Viscasillas Manuel, Martin Piris Nuria et al.

Aerospace components in jet engines need to outstand extreme conditions of high-temperatures and loads. Moreover, these components can sometimes undergo dynamic conditions if impact occurs during the flight. It is critical to understand the behaviour of aerospace alloys under these combined extreme conditions of high-temperature and dynamics loads. One of the most extended alloys used in the compressor and fan stages of commercial jet engines is Ti-6Al4V. The dynamic properties of Ti-6Al-4V are strongly dependent on the microstructure state and the temperature conditions. However, these dependencies are yet not fully understood. Moreover, this alloy can present a wide variety of microstructures depending on the component and manufacturing methods. In this work, we compare the response of five typical Ti-6Al-4V microstructures tested under static and dynamic conditions and different temperatures. The macroscopic response of the alloy is rationalised on the basis of its microstructural state using combined microscopy characterisation and computational modelling. To this end, computational plastic models are constructed and validated against experimental observations. In this way, the relationship between the mechanical properties of each microstructure and the temperature and strain rate conditions can be extracted to optimize the material state under specific dynamics in-service conditions.

Evan Walter Clark Spotte-Smith, Samuel M. Blau, Xiaowei Xie et al.

Measurement(s) molecule • solid electrolyte interphase Technology Type(s) density functional theory • computational modeling technique Factor Type(s) bond type • charge • spin multiplicity Machine-accessible metadata file describing the reported data: https://doi.org/10.6084/m9.figshare.14915256

Racim Radjef, Karyn L. Jarvis, Colin Hall et al.

Plasma-polymerised tetramethyldisiloxane (TMDSO) films are frequently applied as coatings for their abrasion resistance and barrier properties. By manipulating the deposition parameters, the chemical structure and thus mechanical properties of the films can also be controlled. These mechanical properties make them attractive as energy adsorbing layers for a range of applications, including carbon fibre composites. In this study, a new radio frequency (RF) plasma-enhanced chemical vapour deposition (PECVD) plasma reactor was designed with the capability to coat fibres with an energy adsorbing film. A key characterisation step for the system was establishing how the properties of the TMDSO films could be modified and compared with those deposited using a well-characterized microwave (MW) PECVD reactor. Film thickness and chemistry were determined with ellipsometry and X-ray photoelectron spectroscopy, respectively. The mechanical properties were investigated by nanoindentation and atomic force microscopy with peak-force quantitative nanomechanical mapping. The RF PECVD films had a greater range of Young’s modulus and hardness values than the MW PECVD films, with values as high as 56.4 GPa and 7.5 GPa, respectively. These results demonstrated the varied properties of TMDSO films that could in turn be deposited onto carbon fibres using a custom-built RF PECVD reactor.

Editor JFDE

Welcome to this new issue of our Journal of Façade Design and Engineering. We are very pleased to be able to release a new issue under the current global circumstances, to keep supporting research and the engineering of new technologies, materials, and methods for the design of our envelopes. This special issue features a wide range of topics, stemming from research activities of members from the European Façade Network (EFN). The EFN seeks to advance and promote façade design and engineering at a European level and beyond, through inclusive collaboration between European Research centres, Universities, and alumni, resulting in skills and knowledge transfer in education, research, and development. Consequently, this special issue showcases a selection of research experiences presented at two scientific events sponsored by the EFN. The first scientific event was the Conference “FACADES19” held in Lisbon on November 22nd, 2019, which was organised by Dr. Daniel Aelenei from the Department of Civil Engineering at NOVA School of Science and Technology. The second scientific event refers to a special “EFN session“ hosted at the Façade Tectonics 2020 World Congress, held online in August 2020. This session within the larger congress was coordinated by Daniel Artzmann, Mikkel Kragh, Annalisa Andaloro, and Ulrich Knaack. The selection of the papers from both events was based on their relevance to the scope of our journal and went through the double-blind peer review process of the JFDE. We thank all supporters and contributors who made these events a success and especially the authors of the articles compiled in this issue. The Editors in Chief, Ulrich Knaack Tillmann Klein

K.P. Constant

Afsaneh Rabiei