Synthesis and processing effects on magnetic properties in the Fe5SiB2 system
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Lejeune, B. T.↗
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Results for “synthesis and processing”
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Towards a systematic framework for the synthesis of operable process intensification systems
In this work we present an integrated framework to derive intensified designs with guaranteed safety and operability performance. A step-by-step procedure is described featuring: (i) superstructure-based process synthesis using Generalized Modular Representation Framework, (ii) development of advanced multi-parametric control strategies following the PAROC framework and software platform, and (iii) inherent safety analysis at early design stage utilizing quantitative risk assessment. Here, two case studies with increasing intensification complexity, namely heat exchanger network synthesis and reactive distillation column design, are investigated to demonstrate the capabilities of the proposed framework.
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
Effects of Synthesis and Processing on Optoelectronic Properties of Titanium Carbonitride MXene
MXenes, a relatively new class of two-dimensional (2D) transition-metal carbides, carbonitrides, and nitrides, exhibit unique properties such as high electronic conductivity, a wide range of optical characteristics, hydrophilicity, and mechanical stability. Because of the high electronic conductivity, MXenes have shown promise in many applications, such as energy storage, electromagnetic interference shielding, antennas, and transparent coatings. 2D titanium carbide (Ti 3 C 2 T x , where T x represents surface terminations), the first discovered and most studied MXene, has the highest electronic conductivity exceeding 10 000 S cm –1 . There have been several efforts to alter the conductivity of MXenes, such as manipulation of the transition-metal layer and control of surface terminations. However, the impact of the C and N site composition on electronic transport has not been explored. In this study, the effects of synthesis methods on optoelectronic properties of 2D titanium carbonitride, Ti 3 CNT x , were systematically investigated. We show that Ti 3 CNT x , which hosts a mix of carbon and nitrogen atoms in the X layer, has lower electronic conductivity and a blue shift of the main absorption feature within the UV–visible spectrum, compared to Ti 3 C 2 T x . Moreover, intercalants such as water and tetraalkylammonium hydroxides decrease the electronic conductivity of MXene due to increased interflake resistance, leading to an increase in resistivity with decreasing temperature as observed in ensemble transport measurements. When the intercalants are removed, Ti 3 CNT x exhibits its intrinsic metallic behavior in good agreement with Hall measurements and transport properties measured on single-flake field-effect transistor devices. Finally, the dependence of conductivity of Ti 3 CNT x on the presence of intercalants opens wide opportunities for creating MXene-based materials with tunable electronic properties.
36 MATERIALS SCIENCE↗
Improved synthesis of ceramic superconductors with alkaline earth peroxides - Synthesis and processing of Ba2YCu3O(7-x)
Synthesis processes for the preparation of ceramic conductors Ba2YCu3O(7-x) from BaO2 or BaCO3 in flowing O2 or N2 are described, and the characteristics of the materials produced in these processes are compared. Results of EDAX, XRD, SEM, and dc resistivity analyses demonstrated that superconducting materials made from BaO2 were more homogeneous, denser, and more metallic than materials produced from BaCO3, because of the higher reactivity of BaO2. Potential applications of this processes are discussed.
Hepp, A. F.↗
Size tunable synthesis of solution processable diamond nanocrystals
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catalysis (heterogeneous)↗
Laser synthesis and processing of atomically thin 2D materials
Recent advances in laser synthesis and processing of 2D materials are described that address key issues of scalable synthesis, precise heterogeneity control, and transformative manufacturing. Here, laser spectroscopy is used to remotely characterize and optimize the structure and functionality of 2D materials, enabling their in-situ diagnostic-based synthesis and processing.
2D materials↗
Polysiloxanes derived from the controlled hydrolysis of tetraethoxysilane as precursors to silica for use in ceramic processing
Synthesis, properties, and potential applications in ceramic processing for two polysiloxane silica precursors derived from the controlled hydrolysis of tetraethoxysilane (TEOS) are presented. The higher molecular weight TEOS-A is a thick adhesive liquid of viscosity 8000 to 12,000 c.p. having a SiO2 char yield of about 55 percent. The lower molecular weight TEOS-B is a more fluid liquid of viscosity 150 to 200 c.p. having a SiO2 char yield of about 52 percent. The acid catalyzed hydrolysis of TEOS to hydrated silica gel goes through a series of polysiloxane intermediates. The rate of this transition increases with the quantity of water added to the TEOS; thus, for ease of polymer isolation, the amount of water added must be carefully determined so as to produce the desired polymer in a reasonable time. The water to TEOS mole ratio falls in the narrow range of 1.05 for TEOS-A and 0.99 for TEOS-B. Further polymerization or gelation is prevented by storing at -5 C in a freezer. Both polysiloxanes thermoset to a glassy solid at 115 C. The liquid polymers are organic in nature in that they are miscible with toluene and ethanol, slightly souble in heptane, but immiscible with water. For both polymers, results on viscosity versus time are given at several temperatures and water additions. Based on these results, some examples of practical utilization of the precursors for ceramic fabrication are given.
Philipp, Warren H.↗
Robofurnace: A semi-automated laboratory chemical vapor deposition system for high-throughput nanomaterial synthesis and process discovery
Laboratory research and development on new materials, such as nanostructured thin films, often utilizes manual equipment such as tube furnaces due to its relatively low cost and ease of setup. However, these systems can be prone to inconsistent outcomes due to variations in standard operating procedures and limitations in performance such as heating and cooling rates restrict the parameter space that can be explored. Perhaps more importantly, maximization of research throughput and the successful and efficient translation of materials processing knowledge to production-scale systems, relies on the attainment of consistent outcomes. In response to this need, we present a semi-automated lab-scale chemical vapor deposition (CVD) furnace system, called “Robofurnace.” Robofurnace is an automated CVD system built around a standard tube furnace, which automates sample insertion and removal and uses motion of the furnace to achieve rapid heating and cooling. The system has a 10-sample magazine and motorized transfer arm, which isolates the samples from the lab atmosphere and enables highly repeatable placement of the sample within the tube. The system is designed to enable continuous operation of the CVD reactor, with asynchronous loading/unloading of samples. To demonstrate its performance, Robofurnace is used to develop a rapid CVD recipe for carbon nanotube (CNT) forest growth, achieving a 10-fold improvement in CNT forest mass density compared to a benchmark recipe using a manual tube furnace. In the long run, multiple systems like Robofurnace may be linked to share data among laboratories by methods such as Twitter. Our hope is Robofurnace and like automation will enable machine learning to optimize and discover relationships in complex material synthesis processes.
36 MATERIALS SCIENCE↗
Synthesis and characterization of hydroxyapatite from fish bone waste
Waste fish bones is a problem stemming from activities in the field of fisheries and it has not been used optimally. Fish bones contain calcium as natural source that used to synthesize hydroxyapatite (HA). In this research, HA synthesized from waste fish bones as local wisdom in Semarang. The goal are to produce HA with cheaper production costs and to reduce the environmental problems caused by waste bones. The novelty of this study was using of local fish bone as a source of calcium and simple method of synthesis. Synthesis process of HA can be done through a maceration process with firing temperatures of 1000°C or followed by a sol-gel method with firing at 550°C. The results are analyzed using FTIR (Fourier Transform Infrared), XRD (X-Ray Diffraction) and SEM-EDX (Scanning Electron Microscopy-Energy Dispersive X-Ray). FTIR spectra showed absorption of phosphate and OH group belonging to HA as evidenced by the results of XRD. The average grain size by maceration and synthesized results are not significant different, which is about 69 nm. The ratio of Ca/P of HA by maceration result is 0.89, then increase after continued in the sol-gel process to 1.41. Morphology of HA by maceration results are regular and uniform particle growth, while the morphology of HA after the sol-gel process are irregular and agglomerated.
36 MATERIALS SCIENCE↗
Sol-gel synthesis and characterization of SiO{sub 2}/PEG hybrid materials containing quercetin as implants with antioxidant properties
In the present work, Silica/Polyethylene glycol (PEG) hybrid nanocomposites containing an antioxidant agent, the quercetin, were synthesized via sol-gel to be used as implants with antioxidant properties. Fourier transform infrared (FT-IR) analysis proved that a modification of both polymer and quercetin occurs due to synthesis process. Scanning electron microscope (SEM) showed that the proposed materials were hybrid nanocomposites. The bioactivity was ascertained by soaking the samples in a simulated body fluid (SBF).
36 MATERIALS SCIENCE↗
Additively manufactured metal energetic ligand precursors and combustion synthesis
Processes for tailoring the macroscopic shape, metallic composition, mechanical properties, and pore structure of nanoporous metal foams prepared through combustion synthesis via direct write 3D printing of metal energetic ligand precursor inks made with water and an organic thickening agent are disclosed. Such processes enable production of never before obtainable metal structures with hierarchical porosity, tailorable from the millimeter size regime to the nanometer size regime. Structures produced by these processes have numerous applications including, but not limited to, catalysts, heat exchangers, low density structural materials, biomedical implants, hydrogen storage medium, fuel cells, and batteries.
Tappan, Bryce↗
Synthesis and Processing by Design of High-Nickel Cathode Materials
The high demand of lightweight, high energy density batteries for energy storage promotes new materials discovery and development. Despite the large number of battery materials being discovered, very few of them have been commercially deployed, mostly bottlenecked by synthesis and processing – namely, making certain phases with the desired structure and properties to meet the multifaceted performance requirements. Alternative to the traditional trial and error, we present here an in situ study aided synthesis- and processing-by-design approach. With specific examples, we illustrate how to use the approach to identify reaction pathways in synthesis and processing of high-Nickel (Ni) cathode materials for next-generation lithium-ion batteries, thereby ensuring precise control of their structure, morphology, and surface properties. Furthermore, perspectives are provided on the wide applicability of the approach to solving critical issues inherent to high-Ni cathodes and the new directions and opportunities in the area.
36 MATERIALS SCIENCE↗
Applied magnetic field synthesis and processing of iron nitride magnetic materials
Techniques are disclosed concerning applied magnetic field synthesis and processing of iron nitride magnetic materials. Some methods concern casting a material including iron in the presence of an applied magnetic field to form a workpiece including at least one ironbased phase domain including uniaxial magnetic anisotropy, wherein the applied magnetic field has a strength of at least about 0.01 Tesla (T). Also disclosed are workpieces made by such methods, apparatus for making such workpieces and bulk materials made by such methods.
Wang, Jian-Ping↗
Guidelines for Synthesis and Processing of Two-Dimensional [2D] Titanium Carbide (Ti 3 C 2 T x MXene)
Two-dimensional (2D) transition metal carbides, carbonitrides, and nitrides (MXenes) were discovered in 2011. Since the original discovery, more than 20 different compositions have been synthesized by the selective etching of MAX phase and other precursors and many more theoretically predicted. They offer a variety of different properties, making the family promising candidates in a wide range of applications, such as energy storage, electromagnetic interference shielding, water purification, electrocatalysis, and medicine. These solution-processable materials have the potential to be highly scalable, deposited by spin, spray, or dip coating, painted or printed, or fabricated in a variety of ways. Due to this promise, the amount of research on MXenes has been increasing, and methods of synthesis and processing are expanding quickly. The fast evolution of the material can also be noticed in the wide range of synthesis and processing protocols that determine the yield of delamination, as well as the quality of the 2D flakes produced. Furthermore we describe the experimental methods and best practices we use to synthesize the most studied MXene, titanium carbide (Ti 3 C 2 T x ), using different etchants and delamination methods. We also explain effects of synthesis parameters on the size and quality of Ti 3 C 2 T x and suggest the optimal processes for the desired application.
36 MATERIALS SCIENCE↗
Generalized Modular Representation Framework for the Synthesis of Extractive Separation Systems
In this work, a systematic process synthesis and intensification method is presented for extractive separation based on the Generalized Modular Representation Framework (GMF). GMF employs a mass/heat exchange module-based superstructure representation, incorporating detailed thermodynamic model, to investigate conventional or intensified process options for nonideal azeotropic separation without a pre-postulation of plausible unit/flowsheet configurations. Orthogonal Collocation is also applied to enhance GMF representation to obtain intra-module operation information and module dimensionality estimation while maintaining model size compactness. Furthermore, entrainer selection, process synthesis, design, and intensification are examined within a single mixed-integer nonlinear optimization (MINLP) problem. A case study on the separation of ethanol-water mixture is presented to highlight the potential of the proposed approach in deriving optimal and verifiable extractive separation systems.
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
Revealing multiscale competing processes in the solid-state synthesis of single-crystalline layered oxide positive electrodes
Solid-state synthesis involves a web of coupled chemical reactions and physical changes that unfold across multiple scales. Efforts to fine-tune its parameters have historically followed heuristic, trial-driven workflows that demand significant time and resources. In this study, we aimed to open this black box by employing multiscale in situ synchrotron imaging and diffraction. Using LiNi 0.5 Mn 0.3 Co 0.2 O 2 battery positive electrode material as a model system and Ba-based sintering aids, we reveal dopant segregation, intergranular mass transport, and porosity evolution as key drivers of single-crystalline particle formation. Notably, we uncovered a dynamic competition between particle-level grain coalescence and atomic-scale cation disordering, both of which are thermally activated yet have opposing impacts on battery performance. These findings highlight the coupled, multiscale nature of structure development and offer a mechanistic basis for optimizing the solid-state synthesis process. This framework provides a path toward more controlled, efficient, and scalable production of high-performance battery positive electrode materials.
36 MATERIALS SCIENCE↗
Synthesis and processing of lithium-loaded plastic scintillators on the kilogram scale
Plastic scintillators that can discriminate between gamma rays, fast neutrons, and thermal neutrons were synthesized and characterized while considering the performance at the kilogram scale. The synthesis and processing of these plastic scintillators on the kilogram scale required examination of several factors. The examination of these factors was necessitated by the inclusion of 0.1 wt.% lithium-6 to enable detection of thermal neutrons. First, methacrylic acid was used as an additive to solubilize salts of lithium-6, which allow for a thermal-neutron capture reaction that produces scintillation light following energy transfer. Second, a trade-off between scintillation performance and processability was considered because the increasing content of the methacrylic acid that aided processability resulted in a sharp decrease in the light output. The use of small amounts of methacrylic acid (≤3 wt.%) resulted in better performance but required high processing temperatures. At large scales, these high temperatures could initiate exothermic polymerization that results in premature curing and/or defects. Additionally, the deleterious effects of the methacrylic acid may be mitigated by using m-terphenyl as a primary dye rather than 2,5-diphenyloxazole (PPO), which has been traditionally used in organic scintillators. Finally, the curing environment was controlled to avoid defects like cracking and discolouration while maintaining solubility of dopants during curing. For scintillators that were produced from kilogram-scale batches of precursors, the effective attenuation of scintillation light was characterized.
36 MATERIALS SCIENCE↗