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Friction and wear are critical aspects that significantly impact the efficiency and durability of mechanical systems. The demand for improved lubricating oils capable of reducing friction and wear has spurred the exploration of advanced additives. Two-dimensional (2D) transition metal carbides, nitrides, and carbonitrides (MXene), a new class of materials, have emerged as promising additives with exceptional tribological properties. This review paper aims to understand the usability of MXene, specifically the ones derived from Ti₃C₂T_X as anti-friction and antiwear additives in lubricating oils. An elaborate discussion is presented about the synthesis and characterization techniques employed in the synthesis of Ti₃C₂T_X (MXene), emphasizing their unique structural and surface properties that could contribute to their tribological performance, followed by their influence on the lubricant's tribological properties is thoroughly discussed. The underlying anti-friction and anti-wear mechanisms, their ability to form tribofilms on sliding surfaces, reduce direct metal-to-metal contact, and minimize wear are also highlighted. Additionally, the role of MXene in modifying the lubricant's chemical and physical interactions with sliding surfaces is analyzed. This review also attempts to identify and address the roadblocks hindering the use of Ti₃C₂T_X MXene in lubricating oils, such as their aggregation tendencies, stability under extreme conditions, and potential side effects on lubricant properties along with the tentative strategies to overcome these hurdles. Relevant experimental findings in which Ti₃C₂T_X derived 2D nano-sheets have been explored as friction and wear-reducing additives in different lubricating oils are critically assessed. Although these MXene are claimed to be highly effective as lubricant additives in lubricating oils owing to their unique properties and versatile chemistry, further research is urgently needed to address the challenges and optimize the formulation and integration of MXene into lubricating oils for practical implementation. This article comprehensively discusses Ti₃C₂T_X MXene as friction and wear-reducing additives in lubricating oils, highlighting the pressing need for further research and the potential for future developments in this field.

Silicon dioxide nanoparticles (SiO₂ NPs) are widely used to manufacture products for human consumption. However, their large-scale use in many fields poses risks to industrial workers. In this study, we investigated the cytotoxic and inflammatory potential of SiO₂ NPs in the human cell line A549, representing the human alveolar epithelium. The NPs were characterized using energy-dispersive x-ray spectroscopy coupled with scanning electron microscopy, x-ray diffraction, transmission electron microscopy, dispersion, and dynamic light scattering. The effects on A549 cells were monitored by cell adhesion and proliferation using electrical impedance, as well as cell viability, apoptosis, necrosis, and secretion of multiple inflammatory mediators. SiO₂ NPs did not alter the adhesion and proliferation of A549 cells but led to cell death by apoptosis at the highest concentrations tested. SiO₂ NP impacted the secretion of pro-inflammatory (tumor necrosis factor-α, interleukin (IL)-8, monocyte chemoattractant protein-1, eotaxin, regulated upon activation, normal T cell expressed and secreted, vascular growth factor, granulocyte–macrophage colony-stimulating factor, and granulocyte-colony stimulating factor) and anti-inflammatory (IL-1ra and IL-10) mediators. These results indicate that, even with little impact on cell viability, SiO₂ NPs can represent a silent danger, owing to their influence on inflammatory mediator secretion and unbalanced local homeostasis.

The von Neumann architecture used as the basic operating principle in computers has a bottleneck owing to the disparity between the central processing unit and memory access speeds, which leads to high power consumption and speed reduction, reducing the overall system performance. However, feedback field-effect transistors (FBFETs) have attracted significant attention owing to their potential to realize next-generation electronic devices based on their switching characteristics. Therefore, in this study, we configured the logic and static memory functions of an inverter comprising a pull-down resistor and an n-channel FBFET using a mixed-mode simulation. The FBFET has a p–n–p–n structure with a gated p-region on the silicon-on-insulator, where each channel length is 30 nm. These modes can have an on/off current ratio of ∼10¹¹ and a subthreshold swing of less than 5.4 mV dec⁻¹. The proposed device can perform logic operations and static memory functions, exhibiting excellent memory functions such as fast write, long hold, and non-destructive read operations. In addition, the inverter operation exhibits nanosecond-level speed and the ability to maintain non-destructive read functionality for over 100 s. The proposed n-FBFET-based inverter is expected to be a promising technology for future high-speed, low-power logic memory applications.

This study presents an eco-friendly mechanochemical synthesis of cesium lead bromide (CsPbBr₃), eliminating the need of organic solvents and high temperatures. The synthesized CsPbBr₃ powder is used to fabricate poly(methyl methacrylate) (PMMA)-CsPbBr₃ films and CsPbBr₃ nanocrystals (NCs). The photoluminescence (PL) peaks of the emission light are centered at 541 nm, 538 nm, and 514 nm for the CsPbBr₃ powder, PMMA-CsPbBr₃ films, and CsPbBr₃ NCs, respectively, correlating with crystal sizes of 0.96, 0.56, and 0.12 μm, respectively. The PL lifetime analysis reveals decay times (${\tau _1},\,{\tau _2}$) of (4.18, 20.08), (5.7, 46.99), and (5.81, 23.14) in the units (ns, ns) for the CsPbBr₃ powder, PMMA-CsPbBr₃ films, and CsPbBr₃ NCs, respectively. The PL quantum yield of the CsPbBr₃ NCs in toluene is 61.3%. Thermal activation energies for thermal quenching are 217.48 meV (films) and 178.15 meV (powder), indicating improved thermal stability with the PMMA encapsulation. The analysis of the PL intensity decay from water diffusion in the PMMA-CsPbBr₃ films yields 1.70 × 10⁻¹² m² s⁻¹ for the diffusion coefficient of water, comparable to that for water diffusion in pure PMMA. This work demonstrates a scalable, sustainable strategy for CsPbBr₃ synthesis and stability enhancement for optoelectronic applications.

The wear and corrosion resistance of water-based polytetrafluoroethylene (PTFE) coating need to be further improved to cope with various harsh environmental conditions. In this paper, a mulberry-like ZSM-5 molecular sieve was prepared and then was modified to enhance the uniformity, wear resistance and hardness of PTFE coating. In addition, a ZSM-5/MoS₂/PTFE coating was developed by adding MoS₂ in the chemical composition of coatings, which significantly increased the critical cracking thickness of PTFE to 27 μm. The wear amount of ZSM-5/MoS₂/PTFE coating is only 5.7 mg, and after 680 h of salt spray, there is no obvious corrosion on the surface. The friction coefficients under applied loads of 5 N, 10 N, and 20 N are 0.007, 0.057, and 0.055, respectively. The experiment results show that the coating possesses excellent lubrication, wear resistance, and corrosion resistance, and its performance and cost are far superior to commercial products.

Polymethylmethacrylate (PMMA) is commonly used as a support material in graphene transfer. Heat treatment exceeding 250 °C is required to remove the PMMA after the transfer process. However, the transparent flexible substrates conventionally used for graphene transfer generally exhibit low heat resistance. This hinders the complete removal of the PMMA, resulting in low electrical conductivity of graphene. Therefore, we focused on developing heat-resistant transparent polyimide (TPI) films as substrates for graphene transfer. The interactions between the TPI substrates and chemical vapor deposition graphene were systematically investigated. The effects of the TPI surface roughness, chemical composition, and chemical structure of the TPI, and doping effects of the substrate were examined, and a silane coupling agent (SCA) was coated to bring the TPI surface properties closer to those of a quartz glass substrate. Three-layer stacked graphene (3LG) on TPI, in which the –CF₃ group in TPI is replaced with –CH₃, exhibited the highest carrier mobility of 3610 cm² Vs⁻¹ at a constant carrier density after annealing. The sheet resistance of the 3LG on TPI annealed after vapor phase deposition of the SCA was lower than that of the standard TPI and decreased to 82 Ω/sq. after doping with bis(trifluoromethanesulphonyl)amide. This is comparable to the electrical properties of graphene on a quartz glass substrate. Furthermore, after doping, the 3LG/TPI maintained a high optical transmittance of 88.8% at a wavelength of 550 nm. The knowledge obtained from this study will allow graphene flexible transparent conductive films to be transferred onto TPI for use in transparent heaters and solar cells as well as to control the electrical properties for various device applications by modifying the roughness, chemical structure, and coating layers on the surface of the TPI substrate.