Large Surface Research Articles

In situ measurement of environmental $$\gamma$$ radiation dose rates of key nuclides for large radioactive surface sources

In situ measurement of environmental $$\gamma$$ radiation dose rates of key nuclides for large radioactive surface sources

Characterization of PFAS Residuals: A Case Study on PFAS Content in a Firefighting Foam Delivery System of an Aircraft Rescue and Firefighting Vehicle.

When fire suppression systems that held aqueous film forming foams (AFFF) are transitioned to per- and polyfluoroalkyl substance (PFAS)-free firefighting formulations, PFAS can dissolve from the wetted surfaces of the systems and release into the new firefighting formulations. The overall objective of this work was to characterize PFAS residual mass on the wetted surfaces of aircraft rescue and firefighting (ARFF) vehicle on-board fire suppression system components from the water, mixed fire water, and foam concentrate systems with various geometries, materials of construction, and locations within the fire suppression system. The ARFF vehicle components were dismantled from the system after a triple water rinse procedure which removed 19,600 mg total measured PFAS post-TOP assay from the foam concentrate system and 23 mg total measured PFAS post-TOP assay from the water system. Results for total mass of PFAS on each part indicate most of the residuals were present on parts which have large surfaces areas or the rubber or brass parts. For large surface area plastic parts (i.e., foam and water tanks), the overall mass on these parts was greater than other parts even though the PFAS residual concentrations were lower compared to other material types due to larger surface areas for accumulation. Parts constructed of rubber or brass appeared to have higher measured PFAS surface residual concentrations as compared to parts constructed of plastic or stainless steel.

Construction and synthesis of NiCo2O4nanozyme for enhanced antibacterial performance.

Developing effective and low-cost enzyme-like nanomaterials to kill bacteria is vital for human health. Herein, Nanorod-assembled NiCo2O4microsphere were prepared though a facile hydrothermal method, and it showed highly enhanced peroxidase-like activity than pure Co3O4due to its large surface area and abundant active sites. The NiCo2O4possess the ability to catalyze H2O2to generate large amounts of •O2-, which can be used for bacteriostatic application. Especially, the antibacterial system combining the spiky NiCo2O4particles and a low concentration of H2O2(100 μM) exhibits an excellent bacteriostatic efficiency against bothE. coli(94.44%) andS. aureus(93.45%).&#xD.

Hybrid materials based on covalent organic frameworks for photocatalysis

AbstractCovalent organic frameworks (COFs) feature π‐conjugated structure, high porosity, structural regularity, large specific surface area, and good stability, being considered as ideal platform for photocatalytic application. Although single COFs have achieved significant progress in photocatalysis benefiting from their distinctive properties, the COFs‐based hybrids provide an extraordinary opportunity to achieve superior photocatalytic performance. From the perspective of carrier transfer mechanism, a systematic summary of hybrids based on COFs and other functional materials (metal single atoms, metal clusters/nanoparticles, inorganic semiconductors, metal–organic frameworks, and other polymers) can offer valuable guidance for the design of COFs‐based hybrids. In this review, the photocatalytic mechanism for hybrid materials (such as Schottky junction, type II heterojunction, Z‐scheme heterojunction, and S‐scheme heterojunction) is briefly introduced. Subsequently, the performance of COFs‐based hybrids in photocatalytic water splitting, CO2 reduction, and pollutant degradation are comprehensively reviewed. Specifically, the carrier separation and transfer in different types of hybrids are highlighted. Finally, the challenges and prospects of COFs‐based hybrids for photocatalysis are envisaged. The insights presented in this review are expected to be helpful in the rational design of COFs‐based hybrids to obtain outstanding photocatalytic activity.image

Metal-organic frameworks as nanoplatforms for combination therapy in cancer treatment.

The integration of nanotechnology into cancer treatment has revolutionized chemotherapy, boosted its effectiveness while reduced side effects. Among the various nanotherapeutic approaches, metal-organic frameworks (MOFs) stand out as promising carriers for targeted chemotherapy, with the added benefit of enabling combination therapies. MOFs, composed of metal ions or clusters linked by coordination bonds, tackle critical issues in traditional cancer treatments, such as poor stability, limited efficacy, and severe side effects. Their key advantages include customizable size and shape, diverse compositions, controlled porosity, large surface areas, ease of modification, and biocompatibility. This review highlights recent advancements in the use of MOFs for cancer therapy, showcasing their role in both monotherapies and combination strategies. Additionally, it explores the future potential and challenges of MOF-based platforms in tumor treatment.

The Modelling of Pt-Bearing ORR and OER-Active Alloys

Nanoparticles are a mainstay of heterogeneous catalysis. This is in part due to their mesoscopic structure; they can be grown to have large available surface areas which can be both regenerative and durable in reaction. Their utility is possible by the alloys used in their production—however, analysis of their operation is generally at the DFT or molecular dynamics level. This review will present an overview of the post-DFT methods relevant to materials supporting the ORR and OER reactions. Pt-bearing alloys will then be highlighted with a focus on their application in heterogeneous catalysis and the ORR/OER reactions. The current computational approaches to accurately predicting the band properties of the alloys will then be discussed and both the fundamental and applied importance of this modelling will be highlighted.

Functional Nanocellulose Derivatives for Global Environmental Solutions

Nanocellulose, a sustainable and biodegradable material derived from natural cellulose, holds immense potential for addressing global environmental challenges. This article reviews the production methods, structural modifications, and applications of nanocellulose derivatives in environmental contexts, emphasizing their role in water purification, pollutant adsorption, and renewable energy solutions. The systematic literature review highlights the unique properties of nanocellulose, such as high mechanical strength, large specific surface area, and tunable chemical functionalities, which enable its use in various industrial, biomedical, and environmental applications. Results indicate that nanocellulose-based materials outperform conventional materials in efficiency and sustainability, particularly in water treatment and biodegradable packaging. Despite its advantages, challenges remain, including production costs, dispersibility in polymer matrices, and stability under high humidity. These limitations necessitate further research and collaborative innovation to enhance its applicability and affordability.

Ultrasmall Bismuth Nanoparticles Supported Over Nitrogen-Rich Porous Triazine-Piperazine Polymer for Efficient Catalytic Reduction.

The development of inexpensive and reusable nanocatalysts to convert the hazardous pollutant 4-nitrophenol (4-NP) into a valuable platform chemical 4-aminophenol (4-AP) is quite demanding due to environmental and public health concerns. Herein, we report a facile strategy for the preparation of supported Bi nanoparticles (NPs) over the surfaces of nitrogen-rich porous covalent triazine-piperazine-3D nanoflowers (BiNPs@3D-NCTP). SEM and TEM image analysis suggested 3D-flower-like morphology of the materials. The powder X-ray diffraction (PXRD) analysis also confirmed the loading of Bi NPs. N2 sorption analysis suggested BET surface areas of 663 and 364 m2g-1 for the 3D-NCTP and BiNPs@3D-NCTP materials, respectively. The large surface area, bimodal pores and 3D nanoflower architecture enable uniform loading of Bi nanoparticles, while its nitrogen-rich functionality stabilizes and acts as a capping agent restricting further nanoparticle expansion. BiNPs@3D-NCTP showed a 99.85% conversion for the 4-NP to 4-AP within four minutes. The normalized rate constant of 38.3 min-1 mg-1 of BiNPs@3D-NCTP catalyst for reducing of 4-NP suggested its superior catalytic efficiency. Nitrogen-rich functionality activates the catalytic site to accelerate the reaction, while bimodal pores can promote diffusion of reactant molecules. After five catalytic cycles, the nanocatalyst showed high chemical stability and negligible activity loss.

Porous frameworks for uranium extraction from seawater

The utilization of uranium (U) fission energy as a high-density, clean power source plays a pivotal role in mitigating greenhouse gas emissions. Uranium extraction from seawater exhibits superior environmental friendliness compared to terrestrial uranium mining, as it avoids substantial generation of radioactive waste and harmful chemicals. However, conventional adsorbents such as fiber, polymer, and biomass materials exhibit slow adsorption rates and low ion selectivity. Porous frameworks with large inner surface, full host-guest interaction, and site utilization are utilized to improve uranium absorption performance. Consequently, devising and synthesizing materials that enable efficient and cost-effective extraction of U(VI) from seawater poses a formidable challenge. Recently, there has been a considerable surge in academic interest regarding the synthesis and design of porous frameworks. By integrating experimental data, spectroscopic analysis, and theoretical calculations, we have conducted an extensive investigation into the actual performance, underlying principles, and practicality of conventional materials (such as fibers) and novel porous materials serving as adsorbents, photocatalysts, and electrocatalysts for U(VI) extraction from seawater.

Fine-tune the structural components of porous frameworks for photocatalytic hydrogen production.

With the depletion of fossil fuels and increasing pollution problems, green and sustainable energy supply attracts worldwide attention. Hydrogen is a green and high-density energy substance, and photocatalytic hydrogen generation is an effective and sustainable method.Therefore, developing high-performance photocatalysts plays a crucial role in practical application. Porous frameworks with large surface areas and diversified structures are considered promising candidates for photocatalysts. This review summarizes the recent progress on porous frameworks and their derivatives through fine-tuning structural components in terms of building monomers, functional groups, and metal hybridization for photocatalytic production of hydrogen. Adetailed correlation is conducted between the structural features of porous frameworks and photocatalysis capability. In addition, we summarized the advantages of porous materials for photocatalytic hydrogen production and future development.

Electrochemical performance of Li-ion battery-based porous silicon nanowires (PSiNWs) decorated with silver nanoparticles

ABSTRACT In recent years, silicon-based materials have attracted great interest for their use as anode in lithium-ion batteries due to their low charging potential and high specific capacity. Morever, silicon nanowires (SiNWs) have been shown to successfully solve the volume-expansion problem by providing free volumes to accommodate silicon expansion. In this work, we fabricated porous silicon nanowires (PSiNWs) on an n-type silicon wafer using a single low-cost metal-assisted chemical etching (MACE) step. Then, the formed (PSiNWs) nanowires were extracted and covered with silver nanoparticles. To reveal the underlying physical and electrochemical mechanisms, we also process a sample of comparative porous silicon nanowires, ranging in diameter from 50 to 100 nm and having a porosity of approximately 60%. The specific capacity is approximately 3635 mA h g−1 with a Coulomb efficiency of 98.8% in the first charge/discharge cycle for PSiNWs/AgNPs, while PSiNWs exhibit low capacity during the first cycle. This study highlights the design of porous silicon nanowires with a large specific surface area and the structural modification of the surface with silver nanoparticles.

Highly Ordered Bimodal Mesoporous Carbon from ABC Triblock Terpolymers with Phenolic Resol.

Mesoporous carbons (MPCs) with a bimodal distribution of pore diameters are more advantageous than their monomodal counterparts for applications in adsorption, catalysis, and drug delivery systems; however, reports on their fabrication remain limited. In this study, we successfully fabricated bimodal MPCs using a soft template method with poly(2,2,2-trifluoroethyl methacrylate) (PTFEMA)-b-poly(4-vinylpyridine) (P4VP)-b-polystyrene (PS) and resol. The blend samples formed microphase-separated structures comprising PTFEMA spheres, PS cylinders, and matrix domains composed of P4VP and resol, leading to the separation of the PTFEMA and PS domains. The P4VP and resol matrix domains were carbonized at a high temperature of 900 °C, whereas the PTFEMA and PS domains were thermally decomposed. This process resulted in bimodal MPCs with both spherical and cylindrical mesopores. The pore diameters calculated using scanning electron microscopy were approximately 10 and 30 nm, while nitrogen adsorption measurements indicated a large specific surface area with a bimodal pore distribution.

Properties optimisation of nanostructures via machine learning: Progress and perspective

Nanostructures play a vast role in the current Internet of NanoThings (IoNT) era due to remarkable properties and features that precisely impart their desired application functions in catalysis, energy and other fields. The exploration in understanding their minute features caused by the flexibility of compositional and complex atomic arrangement from the synthesis reaction widely opens for the in-depth discovery of their search space such as particle size, morphology and structures that controlled the characteristics. A wide range of possible compositions and various lattice atomic arrangements combined with small particle size distribution and large surface area create grand challenges to copy/differentiate their corresponding specific properties. Thus, the employment of machine learning (ML)-based strategies using the closed-loop experimental data from the nanostructure synthesis to help navigate and optimise for the large classes of data attributes related to the size, morphology and other properties from the trained model are reviewed. The data attributes are assisted by discussions of the selected case studies from the recent literature that highlight different condition nanostructures. The review concludes with a discussion of perspectives on the major challenges in the implementation of ML data-driven design in the field of nanostructure synthesis.

Recent Developments in Applications of G-CuO Nanocomposites for Photocatalytic Dye Removal

Abstract The extensive application of synthetic dyes across industries poses significant environmental challenges, particularly concerning water quality degradation. Regarding the possible solutions, copper oxide (CuO) stands out as a feasible candidate. Being a p-type Nano-heterogeneous semiconductor with a bandgap of 1.2–2.71 eV, CuO is a reasonable choice and widely studied photocatalyst for addressing such challenges. When the wavelength exceeded the UV-visible region, its functionality showed deterioration. At the same time, there are difficulties associated with reproducibility and reusability, as well as rapid electron-hole recombination, which prevent the widespread application of this technology within this spectral range. In an attempt to eliminate this defect, researchers have been investigating strategies to activate CuO under visible light, with one promising approach being carbon nanomaterials such as graphene to form carbon-CuO composites. The unique properties of graphene, i.e., its large surface area and excellent electron mobility, make it a remarkable candidate for the enhancement of CuO photoactivity. This study highlighted the recent progress in the synthesis of graphene-based CuO photocatalysts, with the main characteristic of extending the light absorption capacity of CuO into the visible spectrum. It reveals achievements in material innovations and applications, with a focus on photocatalytic dye degradation. These breakthroughs are a sign that the field is growing in popularity and is evolving.

Synthesis and Characterization of Lithium Phosphate (Li3PO4) as a Solid Electrolyte

Due to its high thermal stability, environmental friendliness, and safety, lithium phosphate (Li3PO4) is used as a solid electrolyte in battery applications, but it is usually used with dopants due to its lower ionic conductivity, which is required for ion transport. However, due to its stability and environmentally friendly aspect, lithium phosphate is still a hot topic among suitable energy materials that need further research to improve its electrochemical properties. In the current work, a novel synthesis of lithium phosphate was proposed from the raw materials lithium carbonate (Li2CO3) and trisodium phosphate dodecahydrate (Na3PO4*12H2O) under suitable stoichiometric conditions using the co-precipitation method. In the set of synthesized samples, a single-phase β-Li3PO4 (named LPO-4) with 99.7% purity and 93.49% yield was successfully prepared under appropriate stoichiometric conditions and pH 13 at 90 °C. The average particle size was 10 nm with a large surface area of 9.02 m2g−1. Electrochemical impedance spectroscopy (EIS) of LPO-4 revealed a conductivity of 7.1 × 10−6 S.cm−1 at room temperature and 2.7 × 10−5 S.cm−1 at 80 °C with a low activation energy of 0.38 eV. This performance is attributed to the morphology of the nanotubes and the smaller particle size, which enlarge the reaction interfaces and shorten the diffusion distance of lithium ions. The kinetic and thermodynamic key parameters showed that the β-Li3PO4 exhibits thermal stability in the room temperature range up to 208.8 °C. All these property values indicate a promising application of lithium phosphate as a solid electrolyte in solid-state batteries and a new route for further investigation.

A promising photocathode for green hydrogen generation from sanitation water without external sacrificing agent: silver-silver oxide/poly(1H-pyrrole) dendritic nanocomposite seeded on poly-1H pyrrole film

Abstract A novel photocathode has shown promise for generating green hydrogen from sanitation water at a rate of 50 µmol/h per 10 cm², using waste water as an electrolyte in a three-electrode cell. This photocathode is composed of two layers: a poly(1H-pyrrole) seeding layer topped with a silver-silver oxide/poly(1H-pyrrole) (Ag-Ag2O-P1HP) dendritic nanocomposite. The nanocomposite exhibits broad light absorption up to 660 nm and possesses a bandgap of 1.8 eV. SEM images reveal that the Ag-Ag2O-P1HP nanocomposite consists of well-ordered semi-spherical nanoparticles, with an average size between 80 and 100 nm. These spherical nanoparticles offer a large surface area, which enhances photon absorption and trapping efficiency. Additionally, the crystalline structure is characterized by a small crystal size of 32 nm, further contributing to the material’s efficiency. Hydrogen generation performance was evaluated by measuring the current density (J ph) under white light and monochromatic light, compared to the dark current (J o). The photocathode’s sensitivity was tested using four different monochromatic wavelengths: 540, 440, 340, and 730 nm. The first three wavelengths – 540, 440, and 340 nm – resulted in high J ph values of −0.19, −0.20, and −0.21 mA/cm², respectively, indicating significant hydrogen production. Conversely, the 730 nm wavelength produced a lower J ph value of −0.17 mA/cm², as the energy at this wavelength is insufficient to induce significant bond vibrations, resulting in limited hydrogen production. The high efficiency, combined with the straightforward fabrication of this photocathode, suggests that it could be scaled up as a prototype for industrial hydrogen generation applications.

Ultralow limit human IgG detection with 2H-MoS2/L-cysteine based plasmonic fiber-optic spectral combs

The detection of human immunoglobulin G (human IgG) provides crucial evidence in diagnosis of infectious diseases and monitoring of therapeutic effects. Here, we propose a plasmonic fiber-optical surface plasmon resonance (SPR) based sensor to realize the ultralow limit human IgG detection. The proposed sensor is fabricated by attaching a mixture of 2H-MoS2 nanosheets with L-cysteine on a gold-coated tilted fiber Bragg grating. The 2H-MoS2 possesses a large specific surface area, where the L-cysteine can enhance the stability of antibody modification. The composite membrane of 2H-MoS2 and L-cysteine can adsorb more probe rabbit anti-human IgG, which can improve sensitivity of the proposed sensor. The experimental results show that the proposed sensor exhibits a response time of approximately 220 s and a sensitivity of 0.11 dB/(ng/ml). The limit of detection of 0.87 ng/ml of the proposed sensor is one order of magnitude lower than those of other fiber-optic SPR human IgG sensors.

Effect of the Chemical Structure of a Self-Assembled Monolayer on the Gas-Sensing Behavior of SnO2 Nanowires.

In this study, detailed investigations of the selective sensing capability of semiconducting metal oxide (SMO)-based gas sensors with self-assembled monolayer (SAM) functionalization were conducted. The selective gas-sensing behavior was improved by employing a simple and straightforward postmodification technique using functional SAM molecules. The chemical structure of the SAM molecules promoted interaction between the gas and SAM molecules, providing a gas selective sensing of SnO2 nanowires (NWs). In addition, a bundle of SnO2 NWs provided a large surface area that could act as a sensing site. SAM functionalization was confirmed by infrared spectroscopy and thermogravimetric analysis, and the selective gas-sensing behaviors were investigated under different sensing conditions. With variations in the chemical structures of the SAM molecules, the selective gas-sensing behaviors also changed as the corresponding intermolecular interaction forces were different. This integration of selective gas sensing and passivation of a sensing surface provides a straightforward approach for the preferred gas sensing of SnO2 NWs. Furthermore, owing to the universal binding characteristics of SAM molecules to the metal oxide surface, this approach can be expanded to other SMO-based gas-sensing platforms.

Exploring the effect of tea dust magnetic biochar on agricultural crops grown in polycyclic aromatic hydrocarbon contaminated soil

Abstract Magnetic biochar is a newly discovered novel material synthesized by adding an external magnetic field to conventional biochar. It exhibits dynamic properties like large surface area, porous cavities, ductility, and many functional groups on the surface. Due to the presence of these features, magnetic biochar has tremendous applications in various fields. The magnetic separation property is particularly beneficial for removing contaminants from soil. Much research has been done in this field, and positive results have been shown in the remediation of heavy metals, polycyclic aromatic hydrocarbons (PAHs), and organic contaminants from soil. Removal of these environmental contaminants is essential because they degrade the soil quality by alternating the physico-chemical activity and microbial diversity. Later, it makes the soil unfavorable for the growth of crops. Although much research has been done in this field and succeeded, little attention has been paid to the effect of magnetic biochar on plant growth. Therefore, in this research, we have synthesized the magnetic biochar from tea dust and applied it to the PAH-contaminated soil to explore the effect of tea dust magnetic biochar on the growth of barley plants.

An Unlabeled Electrochemical Immunosensor Uses Poly(thionine) and Graphene Quantum Dot-Modified Activated Marigold Flower Carbon for Early Prostate Cancer Detection

The activated carbon from marigold flowers (MG) was used to make an unlabeled electrochemical immunosensor to determine prostate cancer. MG was synthesized by hydrothermal carbonization and pyrolysis. MG had a large surface area, was highly conductive, and biocompatible. MG modified with graphene quantum dots produced excellent electron transfer for grafting poly(thionine) (PTH). The amine group of PTH bonded with anti-prostate-specific antigen (Anti-PSA) via glutaraldehyde, forming a layer that improved electron transfer. The binding affinity of the immunosensor, presented as the dissociation constant (Kd), was calculated using the Langmuir isotherm model. The results showed that a lower Kd value indicated greater antibody affinity. The immunosensor exhibited two different linear ranges under optimized conditions: 0.0125 to 1.0 ng mL−1 and 1.0 to 80.0 ng mL−1. The sensor could detect concentrations as low as 0.005 ng mL−1, and had a quantification limit of 0.017 ng mL−1. This immunosensor accurately quantified PSA levels of human serum, and the results were validated using enzyme-linked fluorescence assay (ELFA).