Synthesis and Sintering

Ceramic coatings for extreme environments and energy aystems: A review

Farrokhfar Valizadeh Harzand — 2025-06-26

This paper provides a comprehensive review of wear-resistant ceramic coatings used in extreme environments, such as oil and gas operations, thermal barrier coatings, energy, and industrial applications. It explores various material classes, including oxides, carbides, nitrides, and borides, focusing on their thermal stability, mechanical strength, and resistance to oxidation and wear. The study discusses different deposition techniques, including chemical vapor deposition (CVD), physical vapor deposition (PVD), and plasma spraying, highlighting their advantages and challenges. Key challenges, including brittleness, adhesion issues, and high-temperature oxidation, were explained in detail, along with emerging solutions like high-entropy ceramics, self-healing materials, and computational modeling. The integration of smart monitoring systems and advanced fabrication methods is demonstrated as a promising way for optimizing the durability and performance of ceramic coatings. This review also aims to bridge the existing knowledge gaps, offering insights into the latest advancements and future directions in the development of high-performance ceramic coatings for extreme environments.

Mechanochemical Synthesis of Sulfur Nanoparticles from Industrial Waste for Enhanced Hg(II) Adsorption

L. Karamzadeh — 2025-06-23

In this study, sulfur extracted from gas industry waste was used to adsorb mercury ions from aqueous solutions. To reduce particle size and increase the active surface area, a mechanical synthesis grinding process in a wet environment (water and alcohol) was employed, which showed better performance compared to the dry method. BET experiments and BJH pore size distribution analysis revealed that the processed sulfur exhibited uniform micro- and mesopores in the range of 1–10 nm, which were significantly more suitable for heavy metal adsorption compared to the large and irregular pores in the original sample. Additionally, XRD, FTIR, and SEM analyses confirmed the preservation of the crystalline structure, the formation of S–S bonds, and the production of nanoparticles with varying sizes. The results indicate that wet grinding with alcohol and water is an effective method for enhancing the surface area and improving the adsorption efficiency of mercury ions on sulfur

Physical properties of spin-coated nanocrystalline zinc oxide thin film

Omid Khanali — 2025-06-17

ZnO, in its wurtzite structure, is a widely studied metal oxide due to its unique optical and electronic properties, including efficient excitonic emission at room temperature. Zinc oxide thin films were synthesized through the dehydration of various precursors. In ethanol and mono-ethanolamine, zinc acetate (I) and zinc nitrate (II) were dissolved. Glass substrates were coated using the sol-gel spin coating method (3000 rpm for 10 s), followed by heating at 250 °C. This process was done five times to make the films thicker (and allow them to form five layers on the substrate), and then they were annealed at 450 °C for 3 hours in air, yielding 200 nm-thick films. Where acetate-derived ZnO demonstrated superior performance: 92% optical transmission at 1100 nm (vs. 80% for nitrate), a widened bandgap (3.3 eV), and enlarged crystallite size (74 nm), attributed to reduced defect density and homogeneous morphology. The presence of various vibration modes in the prepared samples was also revealed by Raman spectroscopy (RS) of the annealed films. The presence of concentrated stresses within the coated films is also determined using RS, and the scanning electron microscopy results confirm the Raman E₂ peaks by FE-SEM images.

Synthesis methods and characterization techniques of iron oxide nanoparticles: A Biomedical perspective

Saad Ahmed — 2025-06-17

Iron oxide nanoparticles (IONPs) have emerged as pivotal materials in nanomedicine due to their unique magnetic, catalytic, and biological properties. This review examines a variety of synthesis methods: chemical (co-precipitation, sol-gel, thermal decomposition, microemulsion), physical (ball milling, laser ablation, arc discharge, physical vapor deposition, spray pyrolysis), and biological (plant-mediated, microbial, and biomolecule-assisted) and discusses how these techniques influence nanoparticle size, crystallinity, and surface functionality. We also detail characterization techniques such as TEM, XRD, DLS, and FTIR that are critical for optimizing IONP’s performance in biomedical settings. Despite considerable progress, reproducibility, scale-up, and biocompatibility issues remain. Future efforts should focus on standardizing protocols, integrating real-time monitoring, and conducting extensive safety assessments to facilitate the clinical translation and large-scale production of IONPs for diverse applications.