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Multifunctional silver nanoparticles-based composites for SERS detection and photocatalytic degradation of micro- and/or nano-plastics
(Elsevier BV, 2026-04)
Nguyễn Hoàng Ly
;
HESAM, KAMYAB
;
Yasser Vasseghian
;
Sang-Woo Joo
Micro- and/or nano-plastics (MNPs) pose an emerging environmental issue due to their widespread presence in aquatic habitats, persistence in the environment, and potential toxic effects on ecosystems and public health. Silver nanoparticles (AgNPs) are well-known not only as plasmonic materials but also as mediators of photocatalysis, which is one of the most promising tools for identifying and degrading MNPs. This review covers recent advances in surface-enhanced Raman scattering (SERS) detection and the photocatalytic degradation of common plastics (e.g., polystyrene, polypropylene, polyvinyl chloride, etc.) using multifunctional AgNPs-based composites. These SERS substrates can detect MNPs in contaminated environmental water with consistent signals and high sensitivity. Notably, upon irradiation, these composites produce reactive oxygen species, triggering chain reactions that break down polymer chains into new compounds. Although AgNPs-based composites are stable, their photocatalytic efficiency is often limited by poor solar spectrum utilization, mass transfer resistance, and electron-hole recombination, leading to lower degradation rates and variable results. Some research highlights the ongoing need to improve photocatalyst design, reactor setups, and assessment methods for degradation. Additionally, the possible formation of toxic intermediates raises safety concerns, underscoring the need for further studies on ecotoxicological effects. When combined with other treatment methods, AgNPs-based SERS detection and photocatalysis provide a promising approach for addressing MNPs and other emerging pollutants in water treatment.
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Design of FeCoNiSmNd-co-doped porous carbon catalysts from pulverized coal for radical and non-radical peroxymonosulfate activation in organic pollutant degradation
(Elsevier BV, 2025-11)
Zhen Wu
;
Lisheng Wang
;
Xiaohan Wang
;
Bin Zhao
;
Heliang Fan
Pulverized coal has a good specific surface area, surface activity, and adsorption properties, which can be utilized to construct new carbon materials. In this work, multi-rare-earth elements co-doped coal-based composite catalysts are synthesized using a pyrolysis carbonization route with pulverized coal as the carbon source. The performance for the catalytic activation of persulfate is investigated with TC as the representative contaminant. The results demonstrate that the porous carbon-based catalyst with uniform doping of transition metals and rare earth metals is prepared with a surface area equal to 654 m2/g. This coal-based catalyst has good degradation efficiencies for TC (95.7 %), RhB (100.0 %), MO (90.0 %), and MB (100.0 %) in 30 min, respectively. The MB and RhB could be entirely degraded within 20 and 10 min, respectively. The activation energy of the reaction system is 16.21 kJ/mol. According to the free radical quenching reaction, the degradation of active compounds of tetracycline (TC) is calculated, which showed that O2•−(39.1 %), SO4•− (27.1 %), 1O2 (22.4 %) and •OH (15.6 %) all played important roles during the degradation of TC. The catalyst retains 94.5 % of its degradation efficiency after four cycles of use. The degradation efficiency and reaction rate constants of the system to degrade TC in lake water, tap water and seawater all increased due to the effect of Cl-, from 89.2 % and 0.2126 min−1 to 97.0 % and 0.3466 min−1, respectively, which showed the catalysts used have a good adaptability with different water.
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Photocatalytic CO2 conversions on copper nanoparticles investigated by Raman spectral changes using convolutional neural networks
(Elsevier BV, 2025-10)
Heung Seok Lee
;
Jaerin Choi
;
Jin Yong Lee
;
Ji Eun An
;
Thi Huong Vu
A convolutional neural network (CNN) deep learning process is employed to analyze in situ Raman scattering data for CO2 capture and its photocatalytic conversions onto copper sulfide hollow nanospheres (CuSHNSs) and copper nanocubes (CuNCs) in microalgae solution of Spirulina maxima. Raman spectra under visible light at 633 nm in a microfluidic solution provided representative vibrational marker bands of Cdouble bondO features at ∼2100 cm−1 and CH2/CH3 bending vibrations at ∼1400 cm−1 that are correlated with CO2 reduction products of carbon monoxide (C1) and multi‑carbon species such as propanol (C3), butanol (C4), respectively. Accumulated Raman spectra were trained and analyzed to estimate photocatalytic pathways using CNN algorithm. The presence of Spirulina maxima microalgae on the alteration of photocatalytic processes is studied by analyzing collective Raman spectral changes. The main observation is that strong CO peaks in Raman spectra of CO2 adsorbed by CuNCs almost disappeared after treatment with microalgae, whereas their intensities were slightly increased in case of CuSHNS. The CNN deep learning process for Raman spectra was effective to differentiate photocatalytic mechanisms of CO2 conversion onto nanoparticle surfaces.
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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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Hybrid Photocatalytic Porphyrin-Functionalized UiO-66/BiVO4 for Enhanced CO2 Reduction Using Photosystem II
(Wiley, 2025-09-04)
Van Duc Bui
;
Thi Huong Vu
;
Thi Phuong Anh Tran
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Le Minh Khoa Nguyen
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HESAM, KAMYAB
Harnessing abundant solar energy for sustainable fuel production offers one of the most encouraging strategies to mitigate CO2 emissions. The discovery of novel and efficient photocatalysts to enhance photocatalytic CO2 reduction is important for converting solar energy to fuel. Porphyrin‐functionalized UiO‐66 on a BiVO4 semiconductor is introduced to convert CO2 via photoreactions. Here, the solar‐driven production of carbonaceous feedstocks is reported using a novel photocatalytic material S‐scheme UiO‐66‐TCPP‐BiVO4 heterojunction coupled with the photosystem II (PSII) in a microalgae. Coupling PSII with synthetic catalysts improves the efficiency of light‐harvesting and the CO2 reduction reaction (CO2RR). Electrochemical impedance spectroscopy, transient photocurrent response, photoluminescence lifetime, X‐ray photoelectron spectrometer, transmission electron microscope (TEM), X‐ray diffraction (XRD), and electron spin resonance measurements are conducted to determine the complex structural and electronic properties and the photocatalytic performance. In situ Fourier‐transform infrared spectra provide the CO2RR processes, revealing the mechanism by detailing intermediate formation and energy pathways.
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Nanobioremediation of heavy metals using microorganisms
(Elsevier BV, 2025-09)
HESAM, KAMYAB
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Shreeshivadasan Chelliapan
;
Elham Khalili
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ZULETA MEDIAVILLA, DIANA PATRICIA
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KHORAMI, MAJID
Heavy metals (HMs) in soil are a big threat to environmental and agricultural sustainability. This review discusses the development of the nanobioremediation paradigm (an approach combining nanotechnology and microbiological processes) for the treatment of HM toxicity. Recent advances in nanoparticle (NP)-based approaches to their ability to improve microbial detoxification methods, such as adsorption, redox transformation, and enzyme activation forms of microbial detoxification are discussed. Key findings suggest that many engineered NPs (e.g., zero-valent iron, biogenic metal oxides) can enhance HM immobilization efficiencies and contour microbial performances and functions of the soil microbiome. Still, there are areas of uncertainty regarding NP-microbe-soil interactions, long-term ecotoxicological effects, and applicability at the field level that are critical to be discussed. Future research directions are advised to focus on the eco-designed NPs, optimizing microbial consortia specific to the soil, and interdisciplinary frameworks linking the laboratory methods and materials to the real-world applications.
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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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Exploring the diverse applications of Carbohydrate macromolecules in food, pharmaceutical, and environmental technologies
(Elsevier BV, 2024-01)
Ramaprabha K
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Venkat Kumar S
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Panchamoorthy Saravanan
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R. Rajeshkannan
;
M. Rajasimman
Carbohydrates are a class of macromolecules that has significant potential across several domains, including the organisation of genetic material, provision of structural support, and facilitation of defence mechanisms against invasion. Their molecular diversity enables a vast array of essential functions, such as energy storage, immunological signalling, and the modification of food texture and consistency. Due to their rheological characteristics, solubility, sweetness, hygroscopicity, ability to prevent crystallization, flavour encapsulation, and coating capabilities, carbohydrates are useful in food products. Carbohydrates hold potential for the future of therapeutic development due to their important role in sustained drug release, drug targeting, immune antigens, and adjuvants. Bio-based packaging provides an emerging phase of materials that offer biodegradability and biocompatibility, serving as a substitute for traditional non-biodegradable polymers used as coatings on paper. Blending polyhydroxyalkanoates (PHA) with carbohydrate biopolymers, such as starch, cellulose, polylactic acid, etc., reduces the undesirable qualities of PHA, such as crystallinity and brittleness, and enhances the PHA's properties in addition to minimizing manufacturing costs. Carbohydrate-based biopolymeric nanoparticles are a viable and cost-effective way to boost agricultural yields, which is crucial for the increasing global population. The use of biopolymeric nanoparticles derived from carbohydrates is a potential and economically viable approach to enhance the quality and quantity of agricultural harvests, which is of utmost importance given the developing global population. The carbohydrate biopolymers may play in plant protection against pathogenic fungi by inhibiting spore germination and mycelial growth, may act as effective elicitors inducing the plant immune system to cope with pathogens. Furthermore, they can be utilised as carriers in controlled-release formulations of agrochemicals or other active ingredients, offering an alternative approach to conventional fungicides. It is expected that this review provides an extensive summary of the application of carbohydrates in the realms of food, pharmaceuticals, and environment.
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Metformin-modified polyethersulfone magnetic microbeads for effective arsenic removal from apatite soil leachate water
(Elsevier BV, 2024-01)
Shakila Kalami
;
Ekaterina Diakina
;
Roya Noorbakhsh
;
Sina Sheidaei
;
Shahabaldin Rezania
Arsenic is the hazardous species and still is the global challenge in water treatment. Apatite soil is highly rich in arsenic species, and its mining presents various environmental issues. In this study, novel magnetic microbeads as adsorbent were developed for the elimination of hazardous arsenic ions from apatite soil's aqueous leachate before discharging into environment. The microbeads were fabricated with metformin polyether sulfone after being doped with zero-valent iron (Met-PES/ZVI). The microbeads were characterized using various techniques, including FTIR, XRD, SEM-EDX, VSM, and zeta potential analysis. The developed adsorbent demonstrated a significant elimination in arsenic in aqueous leachate, achieving 82.39% removal after 30 min of contact time, which further increased to 90% after 180 min of shaking. The kinetic analysis revealed that the pseudo-second-order model best represented the adsorption process. The intra-particle diffusion model indicated that the adsorption occurred in two steps. The Langmuir model (R2 = 0.991), with a maximum adsorption capacity of 188.679 mg g−1, was discovered to be the best fit for the experimental data as compared Freundlich model (R2 = 0.981). According to the thermodynamic outcome (ΔG < −20 kJ/mol), the adsorption process was spontaneous and involved physisorption. These findings demonstrate the potential of magnetic Met-PES/ZVI microbeads as an efficient adsorbent for the removal of arsenic from apatite soil aqueous leachate.
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Metal–organic framework‐enabled biomass conversion technologies for microalgae bio‐refinery in the food industry
(Wiley, 2024-08-08)
Sujatha Sadana
;
Manivasagan Rajasimman
;
Senthil Kumar Sanjay
;
Viswanathan Kishore
;
Balasubramani Senthil Rathi
Biomass is a valuable renewable energy adapted as an alternative to traditional fossil fuels. Apart from fuels, biomass is synthesized into highly valuable products that are used in various forms including biofuels, biochemical, bioproducts, packing material, and find practice in pharmaceutical, cosmetics, and nutraceuticals industries. Particularly, microalgae a third‐generation feedstock known for its rich carbon content possesses protein lipids and carbohydrates produces a variety of green products such as bioethanol, biohydrogen, biodiesel, and biomethane, and also fixes carbon emission to a certain amount in the atmosphere. However, microalgae conversion in the presence of a catalyst such as a metal–organic framework (MOF) yields high‐quality valuable products. A MOF is a porous crystalline material where the structure and pore size can be controlled making it suitable for catalytic reactions and appropriate conversion paths. This review briefly explains the prevailing status of microalgae as a sustainable biomass and features its components for microalgae biorefinery into valuable products and its application in the food industry. MOF properties, characteristics and various MOF‐based conversion technologies for biomass conversion with its application are elaborated. In addition, usage of value products produced from microalgae biorefinery in the food industry and its importance is elucidated. In addition, the challenges in integrating biorefinery processes with food industry operations and their solutions are also presented.

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