Search Results (705)

While we are pursuing a fully electrified society, high-energy rechargeable batteries are undergoing intensive investigation. In this respect, atomic and molecular layer deposition (ALD and MLD) have been drawing increasing interest, due to their unmatched capabilities to precisely modify electrodes’ surfaces for better electrochemical performance. In this work, we reviewed the recent studies using ALD/MLD for interface engineering of several important electrode materials, including nickel (Ni)-rich metal oxide cathodes, silicon (Si), and lithium (Li) anodes in lithium-ion and lithium metal batteries. We particularly discussed the most promising coatings from these studies and explored the underlying mechanisms based on experiments and modeling. We anticipate that this work will inspire more studies using ALD/MLD as an important technique for securing new solutions for batteries. Full article

Elevated levels of total ammonia nitrogen (TAN) are recognized as a primary contributor to acute toxicity in aquatic organisms across freshwater aquaculture and mariculture environments. Existing technologies for TAN removal from wastewater are constrained by complex processes, high energy consumption, and an inability to meet discharge standards in a single step. Conventional electrochemical routes often over-oxidize TAN to nitrate, which undermines the goal of achieving truly harmless wastewater. Herein, we use a three-dimensional (3D) electrochemical system packed with particulate electrodes to realize the “TAN to N₂” in one step. The design exploits a synergistic mechanism in which anodic ·OH and HClO cooperatively oxidize TAN while cathodic sites concurrently reduce nitrate nitrogen, turning NH₄⁺ directly to N₂ without nitrate accumulation. The 3D electrochemical system is particularly suitable for marine aquaculture wastewater, especially when addressing the low TAN concentration characteristic. Results show that the 3D system increased N₂ selectivity from 67.90% to 92.06% while stabilizing wastewater pH within a mildly alkaline window. The system operates in situ, enabling direct recycle of culture water and offering a new technological paradigm for harmless, on-site treatment and resource recovery from mariculture wastewater. Full article

Electro-Fenton (EF) technology holds significant promise for degrading recalcitrant organic pollutants. Still, it faces distinct challenges in high-pollutant-load wastewater, including insufficient radical generation, electrode passivation, and mass transfer limitations. This review systematically organizes recent advances in material design and operational strategies to address these issues. We highlight innovative cathode materials (e.g., graphene-based structures, carbon nanotubes, and metal–organic frameworks), stable anodes such as boron-doped diamond, and catalysts tailored for harsh conditions. Key operational improvements are discussed, including pH adaptability, current density optimization, and oxygen supply enhancement. The integration of hybrid systems, such as bio-electro-Fenton and photo-electro-Fenton, is also examined. Looking forward, future research for treating high-pollutant load wastewater should focus on: (1) Developing electrodes and catalysts with superior antifouling properties and long-term stability in high-strength, complex wastewaters; (2) Constructing intelligent control systems capable of real-time response to water quality fluctuations for adaptive parameter optimization; (3) Exploring energy-efficient, self-sustaining EF systems coupled with renewable energy sources or incorporating energy recovery units. This review aims to provide a comprehensive reference for subsequent research endeavors and practical applications related to the treatment technology of EF systems in high-pollutant-load wastewater contexts. Full article

Hydrogen-rich water (HRW) has attracted significant attention for its physiological and therapeutic potential, driving efforts to develop a green and direct production approach. In particular, if solar energy could be utilized to power the process and the power-generation and water-production modules could be integrated into a single device, it would greatly enhance portability and user convenience, making it an ideal solution for personalized healthcare and outdoor applications. We demonstrate solar-assisted proton exchange membrane (PEM) electrolysis using symmetric IrO₂ electrodes at both cathode and anode to directly generate HRW. The symmetric design simplifies manufacturing, mitigates lifetime mismatch and metal-ion cross-contamination. IrO₂ films were electrodeposited on stainless steel substrates and annealed at 400–700 °C. When coupled with a 100 cm² Si solar cell, the electrode annealed at 550 °C—featuring ~6 nm IrO₂ nanocrystals embedded in an amorphous matrix—exhibited the highest hydrogen production rate. At an applied voltage of 4 V, this 550 °C-annealed IrO₂ electrode produced approximately 1800 μmol h⁻¹ of H₂, corresponding to about 44 mL h⁻¹ of H₂ at 25 °C and 1 atm. Corrosion tests show the HRW is less aggressive to iron than DI, RO, and tap water, suggesting better compatibility with metallic components. During water splitting, the oxidation–reduction potential (ORP) rapidly decreases to <−300 mV within 0–10 min and then stabilizes, with the 550 °C–annealed electrode exhibiting the lowest ORP. Upon air exposure, the ORP increases by ~200 mV over 45–70 min yet remains reductive for >120 min, indicating persistent dissolved H₂ and sustained performance. Overall, the symmetric IrO₂ architecture provides a green, stable, and direct route to HRW production. Full article

Ionic liquid (IL)-based electrolytes have garnered significant interest for enhancing lithium-ion battery (LIB) safety due to their non-flammability, thermal stability, high conductivity, and broad electrochemical stability. We propose novel pyrrolinium-based ionic liquids to enhance lithium-ion mobility and address safety concerns in LIBs. This study investigated LiTFSI in [Pyr13] [FSI] ionic liquid for Li-ion batteries. The cyclic stability and rate performance of single-layer full cells with commercial graphite anode and NMC532 cathode were examined for the electrolyte required per cell and compared to those using a carbonate electrolyte (LP30). Electrolytes containing LiTFSI/[Pyr13] [FSI] exhibited satisfactory rate performance and stable cycling for 100 cycles. The reversible capacity was maintained at over 22 mAh for a cycle period of 100 cycles with an electrolyte loading of 161.8 µL/cm². These electrolytes exhibited the highest oxidation stability, surpassing 5.3 V compared to that of the Li⁺/Li reference electrode. Long cycle life of up to 1000 cycles was conducted, showing 80% capacity retention. Post-mortem analysis using scanning electron microscopy (SEM) and micro-Raman spectroscopy allowed observation of LiTFSI/ [Pyr13] [FSI] effects on cathode and anode active particle stability, and reduced formation of secondary reactions between the IL and battery electrodes. Full article

This article investigates the anticorrosive properties of Zr-ZrN coatings, including Zr-(Zr,Hf)N, Zr-(Zr,Ti)N, Zr,Hf-(Zr,Hf,Nb)N, and Zr,Nb-(Zr,Nb)N, deposited on AISI 321 stainless steel substrates. The hardness and elasticity modulus of these coatings, as well as their scratch test strength, were measured. Corrosion current densities were calculated using the polarisation resistance method and by extrapolating the linear sections of the cathodic and anodic curves under electrode polarisation. The structure and composition of the sample surfaces were analysed by transmission electron microscopy. Notably, the nitride coatings reduced the corrosion current density in a 3% aqueous NaCl solution at 25 °C by more than 10 times, from 6.96 for the uncoated substrate to 0.17 μA/cm² for the Zr-(Zr,Ti)N-coated sample. The addition of Ti nitride to Zr-ZrN led to the most significant decrease in the corrosion current density. However, the introduction of Nb caused an increase in the corrosion rate and a decrease in the polarisation resistance, and Hf did not affect the corrosion-protective properties of the studied nitride coatings. Full article

Fiber-based and fabric batteries signify a groundbreaking development in energy storage, allowing for the straightforward incorporation of power sources into wearable fabrics, intelligent apparel, and adaptable electronics. In this study, we introduce a novel strategy for one-step fabrication of a flexible lithium titanate oxide (Li₄Ti₅O₁₂, LTO) anode directly on a copper current collector via electrospinning, eliminating the need for high-temperature post-processing. Based on our previous work with electrospun nanofiber cathodes and carbon-based current collector, we prepared the LTO electrode using polyethylene oxide (PEO) as a binder and carbon additives to enhance mechanical integrity and conductivity. LTO fiber mats detached from the current collector were found to endure multiple instances of bending, twisting, and folding without any structural damage. LTO/Li cells incorporating electrospun fiber LTO electrodes with 72 wt% active material loading deliver a high capacity of 170 mAh g⁻¹ at 0.05 C. In addition, they demonstrate excellent cycling stability with a capacity loss of only 0.01% per cycle over 200 cycles and maintain a capacity of 160 mAh g⁻¹ at 0.1 C. The scalability of the heat-treatment-free method for fabricating flexible LTO anodes, together with the improved mechanical durability and electrochemical performance, offers a promising route toward the development of next-generation flexible and wearable energy storage devices. Full article

Sodium–ion battery capacitors (SIBatCs) synergistically combine battery–type and capacitor–type components in an inter–parallel configuration, simultaneously delivering high energy and power densities. We pioneer the development of quasi–commercial pouch SIBatCs using Na₃V₂(PO₄)₃/activated carbon (NVP/AC) hybrid cathodes and hard carbon anodes. The hybrid design utilizes NVP as an intrinsic sodium source, eliminating complex anode presodiation—an obstacle to industrialization. The AC component fulfills multiple roles—contributing capacitive capacity, enhancing conductivity, and acting as an electrolyte reservoir, which decreases electrode resistivity as well as polarization. In full cells, an optimal NVP/AC mass ratio range of 10:1–2:1 is identified, enabling balanced low resistance, high energy density, exceptional power density, and long cycle life. SIBatCs incorporating R_10/1 (m_NVP:m_AC = 10:1) and R_4/1 (m_NVP:m_AC = 4:1) achieve energy densities of 148.9 Wh kg⁻¹ (81.0 W kg⁻¹) and 120.6 Wh kg⁻¹ (79.3 W kg⁻¹), respectively. Even at ultrahigh power densities of 30.53 and 29.81 kW kg⁻¹, they retain corresponding energy densities of 50.4 and 39.6 Wh kg⁻¹. They exhibit excellent capacity retentions of 32.8% and 41.6% after 5000 cycles—significantly outperforming pure NVP–based cells (18.0%). The hybrid architecture ensures robust performance across a wide temperature range (−30–60 °C). This work presents a scalable solution for high–performance sodium–ion EES hybrid systems. Full article

The significance of this study arises from the urgent need to develop new corrosion inhibitors for the oil and gas industry. These inhibitors should be synthesized from readily available raw materials and be capable of providing effective protection for steel structures against corrosion when exposed to technological hydrochloric acid solutions over a wide temperature range (20–100 °C). The search for such environmentally acceptable and cost-efficient inhibitors is crucial for improving the durability and operational safety of oilfield equipment under aggressive acidic conditions. A new high-temperature corrosion inhibitor for steel in hydrochloric acid solutions has therefore been developed. The inhibitor, designated CATA, is the product of chemical condensation between cinnamaldehyde and 3-amino-1,2,4-triazole. Its protective action is based on the formation of an organic layer up to 12 nm thick, strongly bound to the steel surface. The results suggest with high probability that this protective film consists of polymeric products formed through chemical transformation of CATA on the corroding metal surface. It was shown that the addition of CATA significantly suppresses the electrode processes of steel, affecting both cathodic and anodic partial reactions as well as the kinetics of hydrogen permeation. Adsorption of CATA on steel is satisfactorily described by the Temkin isotherm. The free energy of adsorption (−ΔG_ads) was determined to be 54 kJ mol⁻¹, which is characteristic of chemisorption. This unique inhibition mechanism enables effective corrosion protection of steel in HCl solutions over a wide temperature range (20–100 °C). Under the most aggressive experimental conditions (2 M HCl, 100 °C), the addition of 10 mM CATA achieved an inhibition efficiency of 99.6%, with a corrosion rate of 3.3 g m⁻² h⁻¹, which represents an outstanding result. Furthermore, for spring steels, even in hot HCl solutions (20–60 °C), CATA strongly suppresses hydrogen uptake and allows complete preservation of their ductility. Full article

The increasing demand for sustainable and high-performance energy storage underscores the limitations of lithium-ion batteries (LIBs), notably in terms of finite resources, safety issues, and rising costs. Multivalent metal-ion batteries (MMIBs)—employing Zn²⁺, Mg²⁺, Ca²⁺, and Al³⁺ ions—represent promising alternatives, as their multivalent charge carriers facilitate higher energy densities and greater electron transfer per ion. The widespread availability, lower cost, and favorable safety profiles of these metals further enhance MMIB suitability for large-scale deployment. However, MMIBs encounter significant obstacles, including slow ion diffusion, strong Coulombic interactions, electrolyte instability, and challenging interfacial compatibility. This review provides a systematic overview of recent advancements in MMIB research. Key developments are discussed for each system: electrode synthesis and flexible architectures for zinc-ion batteries; anode and cathode innovation alongside electrolyte optimization for magnesium-ion systems; improvements in anode engineering and solvation strategies for calcium-ion batteries; and progress in electrolyte formulation and cathode design for aluminum-ion batteries. The review concludes by identifying persistent challenges and future directions, with particular attention to material innovation, electrolyte chemistry, interfacial engineering, and the adoption of data-driven approaches, thereby informing the advancement of next-generation MMIB technologies. Full article

The recent increase in end-of-life (EoL) lithium-ion batteries (LiBs) has become a significant concern worldwide. Most studies in the literature have primarily focused on recovering cathode active metals from black mass (BM), whereas the separation of anode–cathode foils, plastics, and casing metals which are the essential components of LiBs has received relatively little attention. To reduce costs and maximize the recovery of valuable metals in subsequent hydrometallurgical or pyrometallurgical processes, EoL LiBs require appropriate pre-treatment. This study aims to scrape off the BM adhering to the electrode foils resulting from gradual crushing and subsequently separate the plastics and copper (Cu) from other metals through a two-step selective flotation process. The results demonstrated that plastics, due to their natural hydrophobicity, could be effectively removed using a frother, achieving more than 95% recovery with less than 5% metallic contamination. Following plastic flotation, Cu particles were floated in the presence of 3418A, yielding a Cu concentrate containing 65.13% Cu with a recovery rate of 96.4%. Additionally, the aluminum (Al) content in the non-floating material, remaining in the cell, increased to approximately 77%. Full article

Inkjet printing enables contactless deposition onto fragile substrates for printed energy-storage devices and supports flexible batteries and supercapacitors with reduced material use. This review examines multilayer and interdigital architectures and analyzes how ink rheology, droplet formation, colloidal interactions, and the printability window govern performance. For batteries, reported inkjet-printed electrodes commonly deliver capacities of ~110–150 mAh g⁻¹ for oxide cathodes at C/2–1 C, with coulombic efficiency ≥98% and stability over 10²–10³ cycles; silicon anodes reach ~1.0–2.0 Ah g⁻¹ with efficiency approaching 99% under stepwise formation. Typical current densities are ~0.5–5 mA cm⁻² depending on areal loading, and multilayer designs with optimized drying and parameter tuning can yield rate and discharge behavior comparable to cast films. For supercapacitors, inkjet-printed microdevices report volumetric capacitances in the mid-hundreds of F cm⁻³, translating to ~9–34 mWh cm⁻³ and ~0.25–0.41 W cm⁻³, with 80–95% retention after 10,000 cycles and coulombic efficiency near 99%. In solid-state configurations, stability is enhanced, although often accompanied by reduced areal capacitance. Although solids loading is lower than in screen printing, precise material placement together with thermal or photonic sintering enables competitive capacity, rate capability, and cycle life while minimizing waste. The review consolidates practical guidance on ink formulation, printability, and defect control and outlines opportunities in greener chemistries, oxidation-resistant metallic systems, and scalable high-throughput printing. Full article

Plant Microbial Fuel Cells (PMFCs) represent a promising technology that uses electroactive bacteria to convert the chemical energy in organic matter into electrical energy. The addition of carbon pellet on electrodes may increase the specific surface area for colonization via bacteria. Use of nutrients such as urea could enhance plant growth. Our study aims to address the following questions: (1) Does carbon pellet layering affect the electrical performance of PMFCs? (2) Does urea treatment of the plants used to feed the PMFCs affect the electrical performance? A new prototype of PMFC has been tested: the plant pot is on the top, drainage water percolates to the tub below, containing the Microbial Fuel Cells (MFCs). To evaluate the best layering setup, two groups of MFCs were constructed: a “Double layer” group (with carbon pellet both on the cathode and on the anode), and a “Single layer” group (with graphite only on the cathode). All MFCs were plant-fed by Spathiphyllum lanceifolium L leachate. After one year, each of the previous two sets has been divided into two subsets: one wetted with percolate from plants fertilized with urea, and the other with percolate from unfertilized plants. Open circuit voltage (mV), short circuit peak current, and short circuit current after 5 s (mA) produced values that were measured on a weekly basis. PMFCs characterized by a “Single layer” group performed better than the “Double layer” group most times, in terms of higher and steadier values for voltage and calculated power. Undesirable results regarding urea treatment suggest the use of less concentrated urea solution. The treatment may provide consistency but appears to limit voltage and peak values, particularly in the “Double layer” configuration. Full article

The paper presents experimental results for a modified pulsed plasma thruster (PPT) with solid propellant, using a coaxial anode–cathode design. Graphite from pencil leads served as propellant, and a tungsten trigger electrode was tested to reduce carbonization effects. Experiments were performed in a vacuum chamber at 0.001 Pa, employing diagnostics such as discharge current/voltage recording, power measurement, ballistic pendulum, time-of-flight (TOF) method, and a Faraday cup. Current and voltage waveforms matched an oscillatory RLC circuit with variable plasma channel resistance. Key discharge parameters were measured, including current pulse duration/amplitude and plasma channel formation/decay dynamics. Impulse bit values, obtained with a ballistic pendulum, reached up to 8.5 μN·s. Increasing trigger capacitor capacitance reduced thrust due to unstable “pre-plasma” formation and partial pre-discharge energy loss. Using TOF and Faraday cup diagnostics, plasma front velocity, ion current amplitude, current density, and ion concentration were determined. Tungsten electrodes produced lower charged particle concentrations than graphite but offered better adhesion resistance, minimal carbonization, and stable long-term performance. The findings support optimizing trigger electrode materials and PPT operating modes to extend lifetime and stabilize thrust output. Full article

This work describes a simple and economical electrochemical route for the generation of mesoporous alumina (MA) particles that can serve as containers for corrosion inhibitors for the active corrosion protection elements of metals when dispersed in organic coatings. The synthesis of precursor slurries was carried out in an electrochemical reactor with aluminum electrodes operating alternately as anodes and cathodes to facilitate metal dissolution and prevent passivation of the electrode surface. The obtained slurries were thermally treated to produce mesoporous alumina particles with adsorbent characteristics suitable for loading corrosion inhibitors. Benzotriazole (BTA) and 8-hydroxyquinoline (8HQ) were chosen as corrosion inhibitors. Dispersed in a commercial polymer matrix and applied to the coating of mild steel samples, the loaded MA improved the corrosion resistance of the coated metal exposed to a simulated marine environment. When physical damage is intentionally caused to expose the underlying metal, the polymer matrix containing BTA-loaded alumina particles retards the corrosion process due to the swelling of the inhibitor from the particles to the exposed bare metal in the scratch. Electrochemical impedance spectroscopy (EIS) measurements showed a marked increase in low-frequency impedance in coatings containing alumina particles, with the BTA-loaded system providing the most durable protection over extended immersion times (with a 50% improvement in corrosion resistance of steel exposed within the scratch). This demonstrates the potential of this approach for long-term corrosion protection applications. Full article