Multilayer Reflective Coatings for BEUV Lithography: A Review

The development of microelectronics is always driven by reducing transistor size and increasing integration, from the initial micron-scale to the current few nanometers. The photolithography technique for manufacturing the transistor needs to reduce the wavelength of the optical wave, from ultraviolet to the extreme ultraviolet radiation. One approach toward decreasing the working wavelength is using lithography based on beyond extreme ultraviolet radiation (BEUV) with a wavelength around 7 nm. The BEUV lithography relies on advanced reflective optics such as periodic multilayer film X-ray mirrors (PMMs). PMMs are artificial Bragg crystals having alternate layers of “light” and “heavy” materials. The periodicity of such a structure is relatively half of the working wavelength. Because a BEUV lithographical system contains at least 10 mirrors, the optics’ reflectivity becomes a crucial point. The increasing of a single mirror’s reflectivity by 10% will increase the system’s overall throughput six-fold. In this work, the properties and development status of PMMs, particularly for BEUV lithography, were reviewed to gain a better understanding of their advantages and limitations. Emphasis was given to materials, design concepts, structure, deposition method, and optical characteristics of these coatings

Tribology of 2D Nanomaterials: A Review

The exfoliation of graphene has opened a new frontier in material science with a focus on 2D materials. The unique thermal, physical and chemical properties of these materials have made them one of the choicest candidates in novel mechanical and nano-electronic devices. Notably, 2D materials such as graphene, MoS2, WS2, h-BN and black phosphorus have shown outstanding lowest frictional coefficients and wear rates, making them attractive materials for high-performance nano-lubricants and lubricating applications. The objective of this work is to provide a comprehensive overview of the most recent developments in the tribological potentials of 2D materials. At first, the essential physical, wear and frictional characteristics of the 2D materials including their production techniques are discussed. Subsequently, the experimental explorations and theoretical simulations of the most common 2D materials are reviewed in regards to their tribological applications such as their use as solid lubricants and surface lubricant nano-additives. The effects of micro/nano textures on friction behavior are also reviewed. Finally, the current challenges in tribological applications of 2D materials and their prospects are discussed

Platinum degradation mechanisms in proton exchange membrane fuel cell (PEMFC) system: A review

Proton Exchange Membrane Fuel Cells (PEMFCs) have the perspective to intensely decrease global emission through environmentally-friendly potential. This review paper summarizes the degradation of platinum catalyst layer that has become a significant issue in the improvement of PEMFCs. The review intends to categorise and provide a clear understanding between disintegration and agglomerate that occurs during platinum degradation. In each process, different degradation mechanisms and their migration processes are presented. The improvement in platinum degradation as a function of increasing the performance of PEMFC is established. Prospects for addressing platinum degradation through the exploration of further experimental and numerical research are recommended. Lastly, this paper through recommendation attempts to prevent platinum degradation and reduces high costs associated with the replacement of catalysts in the PEMFCs

A review of bipolar plates materials and graphene coating degradation mechanism in proton exchange membrane fuel cell

Proton exchange membrane fuel cells (PEMFCs) have the perception to strongly reduce global emissions through an environmentally friendly perspective. Graphene has drawn global attention and has positioned itself as a potential material for bipolar plates application. This study reviews the application of graphene and summarizes the degradation of graphene coating that has become a significant issue in the improvement of PEMFC's performance. In the analysis, the degradation and its dissolution processes are presented. The need to improve the material selection focused mitigation on fabrication defects that act as initiation sites for graphene coating degradation is recommended. Finally, this review through recommendation endeavors to prevent graphene coating degradation and reduces high costs associated with the replacement of bipolar plates in the PEMFCs

Economic evaluation of hybrid electrical systems for rural electrification: A case study of a rural community in Nigeria

Diesel generators have long been in use in rural communities in Nigeria despite the impact of emissions caused by these generators on the environment. Due to the high cost and fluctuation in the diesel price and the need for a greener environment, such electric generating systems seem not to be economical and environmentally friendly and need to be addressed. The potential of utilizing the major renewable energy sources prevailing in the Umuejim Amorka community was investigated based on related site surveys and data collected from each household. This paper also investigates the feasibility and economic viability of employing a hybrid-electric system in rural communities. The HOMER software that analyzes system configuration was used to study the application and functional limitations of each hybridized arrangement. The results showed that the renewable energy (RE) based system, photovoltaic (PV)//battery(B), has the lowest cost of energy (COE) and net profit cost (NPC) compared to the PV/Diesel Generator (DG)/B and standalone DG systems. Although the diesel generator (DG) hybrid-electric system (HES) has lower NPC and COE values compared to PV/DG/B, the DG system has the highest significant pollution emission. Furthermore, the result revealed that the PV/B system has the lowest capital and total costs compared to the other two HESs. Moreso, the PV/B system, has the highest return on investment (ROI), making the system the most economically viable and adjudged to be a better candidate for rural community electrification demands

Utilization of renewable hybrid energy for refueling station in Al-Kharj, Saudi Arabia

Hydrogen is one of the energy carriers that can be produced using different techniques. Combining multiple energy sources can enhance hydrogen production and meet other electrical demands. The hybrid arrangement allows the produced hydrogen to be stored and used when the electrical energy sources are not adequate. In this study, utilizing the meteorological data was investigated using HOMER (Hybrid Optimization of Multiple Energy Resources) software for the optimal solution. The results demonstrated that the "best-optimized system has 270 kW of photovoltaic (PV), 1 unit of 300 kW of wind turbine (WT), 500 kW of electrolyzer, 100 kg/L of the hydrogen tank, 70 units of 1 kWh lithium-ion battery, and 472 kW of the converter. The selected hybrid energy system has the lowest Levelized cost of energy (LCOE), Levelized cost of hydrogen (LCOH), and net present cost (NPC) of $/kg 0.6208,$/kg 9.34, and $ 484,360.00 respectively which judged the system to be the best choice for the proposed hydrogen project in AI-Kharj. This investigation will help stakeholders and policymakers optimize hybrid energy systems that economically meet the hydrogen production and refueling station demands of the AI-Kharj community.Scopu

Understanding the multifunctional anticorrosion protective mechanism of epoxy-based coatings modified with hydrogel and benzotriazole conveying nanotubes for Q235 steel protection in 3.5 % NaCl

Coatings with multiple protective properties are highly desired for anti-corrosion purposes as they overcome the limitations of conventional coatings that have limited functionality in field applications. Thus, this study describes the protective mechanisms of a new class of composite coatings fabricated by embedding benzotriazole (BTA) laden nanotubes prior-functionalized with interfacial wrappings of chitosan hydrogel (CTSH) entrapping excess crosslinking agents (glutaraldehyde (GTRA) or epichlorohydrin (EPIH)) in epoxy (E44) matrix cured with polyamide. The modification led to an improvement in the barrier and physical properties of the composite coatings and introduced shape-memory self-repairing capabilities. Long-term impedance spectroscopy (EIS) complemented with the physical property tests was employed to interrogate the improved barrier properties. The coatings' microstructure and composition analyzed with SEM and EDS reveal the shape-memory self-repairing effect which was further characterized with overtime optical snapshots of samples exposed in a salt-spray chamber. The antibacterial functionality of the composite coatings against some marine bacteria (Marinobacter aquaeolei and Marinobacter salsuginis) was characterized using combined SEM and confocal laser scanning microscopy (CLSM). UV–visible spectrophotometry data reveal the pH-responsive release of the entrapped functional materials from the composite coatings. The experimental findings show that the new composite coatings exhibited intriguing triple-action protective functionalities and were more effective in protecting Q235 carbon steel exposed to 3.5 % NaCl compared to the conventional epoxy coating. This suggests that comparatively, the composite coatings have promising applications in structures that are exposed to sea environments

A review of the electrochemical and galvanic corrosion behavior of important intermetallic compounds in the context of aluminum alloys

Aluminum alloys are widely sought for different applications due to their high strength-to-weight ratio. Most often this increased strength of the alloy is achieved by specific alloying elements and heat treatment processes which give rise to second phases intermetallic particles (IMPs) also known as intermetallic compounds (IMCs). These second phases play a dominant role in the corrosion susceptibility of aluminum alloys. This review provides a systematic survey of the electrochemical, and galvanic corrosion behavior of IMPs in the context of aluminum alloys. A discussion of the electrochemical/galvanic corrosion behavior of selected/important intermetallic compounds that are commonly found in aluminum alloys such as the Q-phase (Al4Cu2Mg7Si8), π-phase (Al8Mg3FeSi6), θ-phase (Al2Cu), S-phase (Al2CuMg), the β-phase (Mg2Si), β-phase (Al3Mg2), δ (Al3Li), η-phase (MgZn2), and β-phase (Al3Fe) is provided. In addition, the limitations in the electrochemical characterization of intermetallic compounds, the research gap, and prospects are also provided in addition to the phenomenon of galvanic polarity reversal and self-dissolution of IMPs

Potential Cycling of Silver Cathodes in an Alkaline CO₂ Flow Electrolyzer for Accelerated Stress Testing and Carbonate Inhibition

The electrochemical reduction of CO2 (CO2RR) holds promise for the reduction of environmentally taxing CO2 emissions, for the carbon-neutral production of valuable fuels and chemicals, and for storage of excess renewable energy from intermittent sources such as wind and solar in chemical products. Durability of cathodes used in high-throughput CO2RR systems is of paramount importance for the commercial readiness of the CO2RR technology. In this study, we investigate the durability of silver-coated gas diffusion electrode cathodes under potential cycling conditions to simulate the impact of repeated cycles of startup and shutdown as might be experienced in connection with a variable renewable power source. We determine that cycling can impact the cathode via two distinct degradation mechanisms: (1) carbonate formation at negative potentials and (2) catalyst layer restructuring and loss in the relatively positive “oxide formation” potential range. We also explore tailored potential cycling as a mechanism for inhibiting carbonate formation by interrupting the high concentration of OH– at the catalyst layer. The findings from this work lend insight into the types of variable potential operating conditions under which CO2RR systems can deliver continuous, robust performance

Handling heat‐stable salts in post‐combustion CO₂ capture: A detailed survey

The generation of heat‐stable salts (HSSs) in alkanolamine solutions for CO2 capture processes, which is adapted for power plant technologies, exists irrespective of the class of amine solution used for the capture process. Their presence do not only trigger decrements in the CO2 absorption capacities of the solvents and contribute to further alkanolamine degradation, but also result in foaming and loss of solvents, which impacts system economics and threatens the environment. HSSs also promote the corrosiveness of the metallic structures of capture systems by lowering the pH and increasing the conductivity of the absorbent solutions. Overall, these effects substantially subvert the reliability and integrity of CO2 capture units. This survey affords sufficient background on the existence of HSSs by unraveling the flow process in a typical alkanolamine‐based CO2 capture unit with respect to their formation points and potential threats. Furthermore, the major HSSs removal and alkanolamine reclamation methodologies (electrodialysis, distillation, ion exchange, electromagnetic separation, and solvent extraction) were comprehensively explored. We believe that this review paper will benefit researchers across disciplines as we continue to explore new and complex solvent formulations to minimize the cost of CO2 capture while maximizing efficiency<br/