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The effect of La and Ce on the microstructure and properties of cast Al Si alloys with high thermal conductivity
(Elsevier BV, 2026-04)
Fubiao Ge
;
Yezeng He
;
Xuping Zhang
;
Reza Behmadi
;
Siyi Sun
The study focused on the impacts of lanthanum and cerium on the microstructure, mechanical properties, and thermal conductivity of Al-6 wt%Si-0.5 wt%Cu-0.6 wt%Fe alloys. Accordingly, it was determined that the synergistic addition of La and Ce significantly refined the alloy structure. In Al-6Si-0.6Fe-0.5Cu-0.3(La + Ce), the SDAS decreased to 13.1 μm and eutectic Si transformed from coarse plates into fine particles; the size and aspect ratio of Si were reduced by 90.13% and 81.48%, respectively. Meanwhile, the length of Fe-rich phases was shortened by 57.51%. Consequently, the alloy exhibited enhanced properties compared with the rare earth-free alloy, such as thermal conductivity up to 159.68 W/(m·K), ultimate tensile strength of 231.3 MPa, and elongation up to 6.89%, corresponding to enhancements of 13.79%, 24.96%, and 118.73%, respectively. The alloy prepared by high-pressure die casting exhibits excellent properties, with thermal conductivity reaching 175.58 W/(m·K), tensile strength of 240.6 MPa, and elongation after fracture of 7.62%. Furthermore, largescale fully formed LED lamp heat sinks have been successfully prepared from this alloy using HPDC; in this way, its engineering applicability has been confirmed. These enhancements are ascribed to eutectic Si refinement, which reduces electron scattering, and rare-earth enrichment at Fe-rich phase interfaces, suppressing their growth and strengthening the matrix. The findings provide an insight into the key mechanism of the rare earth synergy in enhancement of thermo-mechanical properties in AlSi alloys, opening a new way in material design for effective thermal management applications.
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Reduced graphene oxide blended transition metal oxides anode material to uplift performance of the next generation Li-ion storage
(Elsevier BV, 2026-03)
Muhammad Awais Mughal
;
Tauseef Anwar
;
Reza Behmadi
;
Hamed Rahimi
;
Nayab Mughal
Lithium-ion batteries (LIBs) have emerged as a leading energy storage technology, powering everything from portable electronics to electric vehicles due to their high energy density, long cycle life, and low maintenance requirements. Growing demand for high-energy applications has exposed limitations in conventional electrode materials, driving the search for alternatives that offer higher capacity, better stability, and lower costs. Among these, binary transition metal oxides (BMOs) has gained significant attention as a promising anode material because of its excellent safety, non-toxicity, natural abundance, and environmental compatibility. Despite these advantages, BMOs suffers from inherently low electrical conductivity, which restricts electron transport and leads to poor rate performance—a major barrier to its widespread adoption in commercial batteries. To address these challenges, researchers have developed innovative strategies, such as combining BMOs with conductive additives like carbon or graphene to enhance electron transfer, engineering nanostructured morphologies to shorten ion diffusion pathways, and designing hybrid composites that leverage the strengths of multiple materials. Notably, graphene-based modifications have proven particularly effective, as graphene's exceptional conductivity, mechanical flexibility, and large surface area not only improve charge transfer but also mitigate volume expansion during cycling. These advances have significantly boosted the electrochemical performance of the BMO based-anode material, enabling higher capacities and longer lifespans. This review examines the progress in optimizing BMOs with a focus on graphene-enhanced composites that push the boundaries of rate capability and cycling stability. By analyzing recent breakthroughs and remaining obstacles, we highlight the path forward for developing next-generation LIBs that meet the escalating demands of modern energy storage.
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Tailoring high-entropy alloys for cutting-edge hydrogen evolution electrocatalysis
(Elsevier BV, 2025-12)
Akbar Hojjati-Najafabadi
;
Reza Behmadi
;
Yezeng He
;
HESAM, KAMYAB
;
Yasser Vasseghian
This paper provides a general overview of high-entropy alloys (HEAs) as future electrocatalysts for the hydrogen evolution reaction (HER). Growing energy demands worldwide and the need to mitigate climate change have placed attention on the efficient, sustainable production of hydrogen through electrochemical water splitting. Traditional noble-metal electrocatalysts such as platinum (Pt) possess excellent HER activity but are burdened by exorbitantly inhibitive cost, scarcity, and poisoning sensitivity. High-entropy alloys that consist of five or more major components in nearly equimolar proportions offer a paradigmatic solution due to their unique structural and electronic properties. High configurational entropy, lattice distortion, sluggish diffusion, and synergistic "cocktail" effects, in combination, enhance the catalytic activity of these alloys. Improved synthesis techniques of HEAs in nanoparticle, nanowire, and porous network forms have been discovered to exhibit high HER activity with low overpotentials and long-term durability. This review critically explores the fundamental principles of HER, the design principles of HEA electrocatalysts, and their applications in catalysis, with special focus on directions for future research to realize their full potential.
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High-performance supercapacitors based on NiMn layered double hydroxides/Ni3S2 nanocomposite
(Elsevier BV, 2025-04-01)
Yezeng He
;
Xinfeng Liu
;
Ke He
;
Hesam Kamyab
;
Lalitha Gnanasekaran
Layered double hydroxide (LDH), an emerging electroactive material, receives significant attention in storage and energy conversion area due to its excellent ion insertion and exchange capacity. Transition metal sulfides with multiple oxidation states and redox reactions maintain high-power density. In this research, NiMn-LDH on transition metal sulfides M − S (M = Ni, Co, Mn, Fe) are synthesized. Of these, NiMn-LDH/Ni3S2 demonstrates excellent electrochemical efficiency. In the three-electrode system, NiMn-LDH/Ni3S2 electrode achieves high specific capacitance of 2028.38 mF cm⁻2 at 1 mA cm⁻2 and excellent cycling stability of 69.53 % retention after 5000 cycles at 10 mA cm⁻2. The device consisting of activated carbon and NiMn-LDH/Ni3S2 exhibits a remarkable energy density of 63.06 Wh kg⁻1 at a power density of 1599.94 W kg⁻1. The NiMn-LDH/Ni3S2 electrode demonstrates an effective pseudo-capacitance performance and holds a great promise for electrodes in capacitive energy storage devices. © 2025 Elsevier B.V.
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Controllable synthesis of nanostructured flower-like cadmium sulfides for photocatalytic degradation of methyl orange under different light sources
(Elsevier BV, 2024-03)
Akbar Hojjati-Najafabadi
;
Elahe Farahbakhsh
;
Golnaz Gholamalian
;
Peizhong Feng
;
Fatemeh Davar
This study focuses on the synthesis and characterization of cadmium sulfide nanostructures by coprecipitation method. The materials are characterized by X-ray diffraction, scanning electron microscopy, Fourier transform infrared, and Raman spectroscopy. The bandgap of the nanostructures was calculated under different conditions ranged between 2.8 and 2.4 eV and the materials have flower-like morphology in a cubic crystal system. Photocatalytic degradation of methyl orange dye was investigated under different radiation sources (sunlight, ultraviolet light, xenon light, and sunlight simulator). The effect of pH, initial dye concentration, and photocatalyst concentration on dye degradation was examined to show good degradation performance upon exposure to sunlight, UV light and visible light radiation. The results showed that by reducing the pH, degradation was improved, showing good performance at pH 3 with 85 % within 90 min. In addition, the optimal conditions for dye degradation were observed at concentration of 10 mg, methyl orange dye initial concentration of 10 g/L, and pH of 3. A 100 % degradation of methyl orange dye occurred in 90 min of visible light radiation, suggesting the potentiality of cadmium sulfide nanostructures under the effect of UV irradiation for cleaner production and complete elimination of the dye from polluted water sources, thus contributing to environmental enhancement.

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