Search Results (93)

Wafer cleaning after chemical mechanical planarization (CMP) is a critical processing step for copper metallization in integrated circuits. Post-CMP cleaning (PCMPC) commonly combines surface (electro)chemistry with the tribology of brush scrubbing to remove CMP residues from wafer surfaces. While the complex mechanisms of brush-operated PCMPC are supported by this combination, the conventional electroanalytical methods of assessing PCMPC efficiency are typically operated in the absence of surface brushing. Using a model experimental system with tartaric acid (TA) as a cost-effective cleaner of Cu-oxides, we illustrate here how post-CMP Cu samples can be electrochemically examined using brush cleaning to design/assess PCMPC test solutions. A pH-neutral cleaning solution is employed, where TA also serves as a partial dissolution suppressor of Cu, and CMP-treated wafer samples are scrubbed with a commercial PCMPC brush as sample surfaces are simultaneously probed with electrochemical measurements. The results show the active roles of tribology/lubrication and surface chemistry in the removal of CMP residues. The electrochemically determined residue removal efficiencies of PCMPC are found to be ~97% and ~56% in the presence and in the absence of surface brushing, respectively. The implications of these findings are explored in the general context of evaluating PCMPC formulations. Full article

The conventional spent lithium-ion batteries (LIBs) recycling method suffers from complex processes and excessive chemical consumption. Hence, this study proposes an electrochemical strategy for achieving reductant-free leaching of high-valence transition metals and efficient separation of valuable components from spent cathode sheets (CSs). An innovatively designed sandwich-structured electrochemical reactor achieved efficient reductive dissolution of cathode materials (CMs) while maintaining the structural integrity of aluminum (Al) foils in a dilute sulfuric acid system. Optimized current enabled leaching efficiencies exceeding 93% for lithium (Li), cobalt (Co), manganese (Mn), and nickel (Ni), with 88% metallic Al foil recovery via cathodic protection. Multi-scale characterization systematically elucidated metal valence evolution and interfacial reaction mechanisms, validating the technology’s tripartite innovation: simultaneous high metal extraction efficiency, high value-added Al foil recovery, and organic removal through single-step electrochemical treatment. The process synergized the dissolution of CM particles and hydrogen bubble-induced physical liberation to achieve clean separation of polyvinylidene difluoride (PVDF) and carbon black (CB) layers from Al foil substrates. This method eliminates crushing pretreatment, high-temperature reduction, and any other reductant consumption, establishing an environmentally friendly and efficient method of comprehensive recycling of battery materials. Full article

Research on bionic superhydrophobic surfaces draws inspiration from the microstructures and wetting mechanisms of natural organisms such as lotus leaves, water striders, and butterfly wings, offering innovative approaches for developing artificial functional surfaces. By synergistically combining micro/nano hierarchical structures with low surface energy chemical modifications, researchers have devised various fabrication strategies—including laser etching, sol-gel processes, electrochemical deposition, and molecular self-assembly—to achieve superhydrophobic surfaces characterized by contact angles exceeding 150° and sliding angles below 5°. These technologies have found widespread applications in self-cleaning architectural coatings, efficient oil–water separation membranes, anti-icing materials for aviation, and anti-biofouling medical devices. This article begins by examining natural organisms exhibiting superhydrophobic properties, elucidating the principles underlying their surface structures and the wetting states of droplets on solid surfaces. Subsequently, it categorizes and highlights key fabrication methods and application domains of superhydrophobic surfaces, providing an in-depth and comprehensive discussion. Full article

With increasing energy demand and depletion of fossil fuels, the search for renewable energy sources has become imperative. Among them, biomass energy has attracted significant attention as it is clean, renewable, and abundant. This review summarizes recent advances in the electroreduction of the biomass-derived platform compound furfural (FF) for producing high-value fuels and chemicals. First, the principles and mechanisms of electrocatalysis are introduced, followed by a detailed analysis of reaction pathways for electrocatalytic hydrogenation, hydrogenolysis, and dimerization. Subsequently, the review highlights the research progress on the electrochemical reduction of FF to hydrofuroin (HDF, a precursor for jet fuel), analyzing its reaction mechanisms and summarizing the effects of catalytic materials and reaction conditions on product selectivity and faradaic efficiency. Additionally, it provides an overview of catalyst selection for both hydrogenation and hydrogenolysis processes. Studies indicate that Cu-based catalysts exhibit superior performance in hydrogenation and hydrogenolysis, with the latter being more favorable under low pH. In contrast, metal-doped carbon catalysts demonstrate enhanced activity in dimerization reactions. Reaction conditions also significantly influence product distribution, with lower reduction potentials generally favoring dimerization. Finally, the challenges and future directions in FF electroreduction are discussed, including the need for deeper understanding of competing pathways, improved electrode stability, and scalable reactor design. The integration of electrocatalytic with renewable energy offers a green and sustainable approach for the efficient utilization of biomass-derived compounds, holding substantial research significance and application potential. Full article

This review paper presents an overview of fuel cell electrochemical systems that can be used for clean large-scale power generation and energy storage as global energy concerns regarding emissions and greenhouse gases escalate. The fundamental thermochemical and operational principles of fuel cell power generation and electrolyzer technologies are discussed with a focus on high-temperature solid oxide fuel cells (SOFCs) and solid oxide electrolysis cells (SOECs) that are best suited for grid scale energy generation. SOFCs and SOECs share similar promising characteristics and have the potential to revolutionize energy conversion and storage due to improved energy efficiency and reduced carbon emissions. Electrochemical and thermodynamic foundations are presented while exploring energy conversion mechanisms, electric parameters, and efficiency in comparison with conventional power generation systems. Methods of converting hydrocarbon fuels to chemicals that can serve as fuel cell fuels are also presented. Key fuel cell challenges are also discussed, including degradation, thermal cycling, and long-term stability. The latest advancements, including in materials selection research, design, and manufacturing methods, are also presented, as they are essential for unlocking the full potential of these technologies and achieving a sustainable, near zero-emission energy future. Full article

Water electrolysis for hydrogen production is of great importance for the reliable use of renewable energy sources to have a clean environment. Electrolyzers play a key role in achieving the carbon-neutral target of 2050. Among the different types of water electrolyzers, proton exchange membrane water electrolyzers (PEMWEs) represent a well-developed technology that can be easily integrated into the smart grid for efficient energy management. In this study, a discrete dynamic mathematical model of a PEMWE was developed in MATLAB/Simulink to simulate cell performance under various operating conditions such as temperature, inlet flow rate, and current density loads. A lab-scale test bench was designed and set up, and a 5 cm² PEMWE was tested at different temperatures (40–80 °C) and flow rates (3–12 mL/min), obtaining Linear Sweep Voltammetry (LSV), Cyclic Voltammetry (CV), Chrono-potentiometry (CP), and Electrochemical Impedance Spectroscopy (EIS) results for comparison and adjustment of the dynamic model. Sensitivity analysis of different operating variables confirmed that current density and temperature are the most influential factors affecting cell voltage. The parametric sensitivity of various chemical–physical and electrochemical parameters was also investigated. The most significant ones were estimated via non-linear least squares optimization to fine-tune the model. Additionally, strong correlations between these parameters and temperature were identified through regression analysis, enabling accurate performance prediction across the studied temperature range. Full article

The increasing global demand for clean water is driving the development of advanced wastewater treatment technologies. Graphitic carbon nitride (g-C₃N₄) has emerged as an efficient photocatalyst for degrading organic pollutants, such as synthetic dyes, due to its exceptional thermo-chemical stability. However, its application is limited by an insufficient specific surface area, low photocatalytic efficiency, and an unclear degradation mechanism. In this study, we aimed to enhance g-C₃N₄ by doping it with elemental chlorine, resulting in a series of Cl-C₃N₄ photocatalysts with varying doping ratios, prepared via thermal polymerization. The photocatalytic activity of g-C₃N₄ was assessed by measuring the degradation rate of RhB. A comprehensive characterization of the Cl-C₃N₄ composites was conducted using SEM, XRD, XPS, PL, DRS, BET, EPR, and electrochemical measurements. Our results indicated that the optimized 1:2 Cl-C₃N₄ photocatalyst exhibited exceptional performance, achieving 99.93% RhB removal within 80 min of irradiation. TOC mineralization reached 91.73% after 150 min, and 88.12% removal of antibiotics was maintained after four cycles, demonstrating the excellent stability of the 1:2 Cl-C₃N₄ photocatalyst. Mechanistic investigations revealed that superoxide radicals (·O₂⁻) and singlet oxygen (¹O₂) were the primary reactive oxygen species responsible for the degradation of RhB in the chlorine-doped g-C₃N₄ photocatalytic system. Full article

Polyethylene microplastics (PE MPs) pose a severe threat to aquatic ecosystems and human health, demanding urgent, sustainable remediation strategies. While the electro-Fenton process is widely used for treating refractory pollutants in wastewater, its standalone application remains inadequate for PE MPs due to their stable chemical structure and complex molecular chains. This study introduces a green and sustainable magnetite-activated persulfate electro-Fenton (Mt-PS-EF) system designed to address these limitations while aligning with circular-economy principles. By synergizing Fe₃O₄ catalysis, persulfate activation, and electrochemical processes, the Mt-PS-EF system achieves efficient PE MP degradation through hydroxyl (·OH) and sulfate (SO₄·⁻) radical-driven oxidation. Under optimized conditions (60 mg/L PE, 40 mM persulfate, 150 mg Fe₃O₄, 20 h treatment), a 90.6% degradation rate was attained, with PE MPs undergoing chain scission, surface erosion, and release of low-molecular-weight organics. Crucially, the magnetic property of magnetite facilitated the recovery and reuse of the catalyst, significantly reducing material costs and minimizing waste generation. By integrating catalytic efficiency with resource recovery, this work advances scalable, eco-friendly solutions for microplastic pollution mitigation, directly contributing to UN Sustainable Development Goals (SDGs) 6 (Clean Water) and 14 (Life Below Water). The findings highlight the potential of hybrid electro-Fenton technologies in achieving sustainable wastewater treatment and plastic waste management. Full article

Sputtering onto liquids is rapidly gaining attention for the green and controlled dry synthesis of ultrapure catalysts nanomaterials. In this study, we present a clean and single-step method for the synthesis of gold nanoparticles directly in polyethylene glycol (PEG) liquid using radio frequency (RF) magnetron sputtering and by subsequently transferring them to Nafion ionomer, fabricating a catalyst-coated membrane (CCM), an essential component of the proton exchange membrane water electrolyzer (PEMWE). The samples were systematically characterized at different stages of process development. The innovative transfer process resulted in a monodispersed homogeneous distribution of catalyst particles inside CCM while retaining their nascent nanoscale topography. The chemical analysis confirmed the complete removal of the trapped PEG through the process optimization. The electrochemical catalytic activity of the optimized CCM was verified, and the hydrogen evolution reaction (HER) in acidic media appeared outstanding, a vital step in water electrolysis toward H₂ production. Therefore, this first study highlights the advantages of RF sputtering in liquid for nanoparticle synthesis and its direct application in preparing CCM, paving the way for the development of innovative membrane preparation techniques for water electrolysis. Full article

A plasma-assisted electrochemical deposition (PAECD) technology was introduced to coat a cast iron brake disc for the possible reduction of brake wear and brake wear particle (BWP) emission. The majority of the coating consisted of alumina (Al₂O₃), determined by energy dispersive X-ray (EDX) analysis and X-ray diffraction (XRD) analysis. To validate the above strategy of the coating technology for automotive brake corners, one brake stock rotor was replaced by a PAECD-coated rotor for a vehicle road test. After the road test, weight loss of the brake components (rotors and pads) was measured, showing that the alumina coating can reduce the brake wear by more than 70%. BWPs were also collected from wheel barrels, spokes, and brake friction rings of the coated and uncoated rotors during the road test. A morphology and chemical composition analysis of the collected BWPs indicated that the coating could reduce BWP generation from the original sources and avoid a metal pick-up (MPU) issue, leading to less metallic content in BWPs. This alumina coating may provide the auto sector with a sustainable approach to overcome the brake dust emission problem, evidenced by less wear of the brake pads, minimal wear of the coated brake rotor, less MPUs, and a clean wheel rim on the coated brake corner. Full article

Lithium-ion batteries are a promising type of energy storage for renewable energy applications owing to their high energy density. Extensive research has therefore been carried out, utilizing both experimental and computational methods to aid in a deeper understanding of these types of batteries. This research work presents an electrochemical–thermal computational model for lithium-ion battery cells that analyzes electrical behavior, chemical behavior and thermal behavior. This computational model is developed by implementing a finite volume solution of a set of partial differential equations that describe this behavior in the anode, separator and cathode. These differential equations are mass conservation, charge conservation and energy conversion. In addition, the Butler Volmer equation is used to describe the exchange of lithium ions between the solid electrodes and the electrolyte and empirical relationships are used to describe the equilibrium electrical potentials. The results obtained by the developed MATLAB program are validated against those published in the literature. On top of the comparisons, a number of additional results are generated using the developed computational tool such as profiles of the lithium-ion concentrations, profiles of the voltage and profiles of the temperature across the battery. In addition, the voltage output and temperature as a function of time for specified current flows are given. The effect of including a temperature simulating routine in the battery model is assessed. This work contributes toward the advancement of renewable and clean energy by providing a tool and results that can be used to better understand battery energy storage. Full article

As a typical phenolic residue and pollutant, 2,4-D wastewater has a complex composition and high salt content, which makes it difficult for a single wastewater treatment method to meet the discharge standard. To address this challenge, this study explores an integrated electrochemical treatment approach that specifically targets 2,4-D high-salt organic wastewater with the aim of achieving the resource utilization of the wastewater and optimizing the operating parameters of each treatment unit. The results show that under the best experimental conditions, the chemical oxygen demand (COD) is significantly reduced to 200 mg/L, and the COD removal efficiency is as high as 99.67%. In addition, the recovery efficiency of phenolic substances 2,4-dichlorophenol, glycolic acid, and sodium chloride in wastewater reached 99.70%, 99.99%, 96.89%, and 80%, respectively. Phenols are used as raw materials for 2,4-D production, glycolic acid is widely used as a cleaning agent in industry, and the purity of recycled sodium chloride is as high as 99.08%, which can be reused as industrial salt. According to the treatment cost estimate, the benefit of recycling can offset the cost of wastewater treatment and may generate a certain economic surplus. This method is of great significance for the treatment of furfural wastewater and the realization of zero discharge of wastewater, which not only contributes to environmental protection but also promotes the sustainable utilization of resources. Full article

This paper focuses on the critical role of long-duration energy storage (LDES) technologies in facilitating renewable energy integration and achieving carbon neutrality. It presents a systematic review of four primary categories: mechanical energy storage, chemical energy storage, electrochemical energy storage, and thermal energy storage. The study begins by analyzing the technical advantages and geographical constraints of pumped hydro energy storage (PHES) and compressed air energy storage (CAES) in high-capacity applications. It then explores the potential of hydrogen and synthetic fuels for long-duration clean energy storage. The section on electrochemical energy storage highlights the high energy density and flexible scalability of lithium-ion batteries and redox flow batteries. Finally, the paper evaluates innovative advancements in large-scale thermal energy storage technologies, including sensible heat storage, latent heat storage, and thermochemical heat storage. By comparing the performance metrics, application scenarios, and development prospects of various energy storage technologies, this work provides theoretical support and practical insights for maximizing renewable energy utilization and driving the sustainable transformation of global energy systems. Full article

For centuries, fossil fuels have been the primary energy source, but their unchecked use has led to significant environmental and economic challenges that now shape the global energy landscape. The combustion of these fuels releases greenhouse gases, which are critical contributors to the acceleration of climate change, resulting in severe consequences for both the environment and human health. Therefore, this article examines the potential of hydrogen as a sustainable alternative energy source capable of mitigating these climate impacts. It explores the properties of hydrogen, with particular emphasis on its application in industrial burners and furnaces, underscoring its clean combustion and high energy density in comparison to fossil fuels, and also examines hydrogen production through thermochemical and electrochemical methods, covering green, gray, blue, and turquoise pathways. It discusses storage and transportation challenges, highlighting methods like compression, liquefaction, chemical carriers (e.g., ammonia), and transport via pipelines and vehicles. Hydrogen combustion mechanisms and optimized burner and furnace designs are explored, along with the environmental benefits of lower emissions, contrasted with economic concerns like production and infrastructure costs. Additionally, industrial and energy applications, safety concerns, and the challenges of large-scale adoption are addressed, presenting hydrogen as a promising yet complex alternative to fossil fuels. Full article

The diffusion-bonding technique has been utilized to join various Al alloys (AA1060, AA2024, AA3003) to Cu for bimetallic anode application. This process aims to achieve robust metallic continuity to facilitate electron transfer, while carefully managing the growth of the intermetallic layer at the bonding interface. This control preserves the active volume of aluminum and prevents excessive brittleness of the anode. Optimization efforts have focused on different pressures, surface treatments of parent materials, and bonding parameters (temperature 450–500 °C and time 5–60 min). The optimal conditions identified include low bonding pressures (8 MPa), surface treatment involving polishing followed by chemical cleaning of the surfaces to be bonded, and energetic bonding conditions tailored to each specific aluminum alloy. Preliminary electrochemical characterization via cyclic voltammetry (CV) tests has demonstrated high reversibility intercalation/deintercalation reactions for up to seven cycles. The presence of the different alloying elements appears to contribute significantly to maintaining the high intercalation/deintercalation reaction reversibility without considerable modification of the reaction potentials. This effect may be attributed to alloying elements effectively reducing the overall alloy volume expansion, potentially forming highly reversible ternary/quaternary active phases, and creating a porous reaction layer on the exposed aluminum surface. These factors along with the influence of the Cu parent material collectively reduce the stress during volume expansion, which is the responsible phenomenon of the anode degradation in common Al anodes. Full article