Nanoparticle Composite Materials Research Articles

NiAl LDH nanosheets based on Ag nanoparticles-decoration and alkali etching strategies for high performance supercapacitors

Layered double hydroxides (LDHs) represent a category of two-dimensional layered intercalation materials, showing significant potential as electrode materials for the production of high-energy-density supercapacitors due to their tunable composition, ease of synthetic modification, and low cost. Here, we constructed alkali-etched NiAl LDH-OH nanosheets/Ag nanoparticles (NPs) composite material (Ag@NiAl LDH-OH) for high-performance supercapacitors through a simple solvent-thermal reaction. The alkali treatment is employed to selectively etch some Al3+ ions, generating cation vacancies as active sites for energy storage. Additionally, under the simultaneous influence of strong alkalis and vacancies, the interlayer spacing of LDHs expands, aiding in the promotion of interlayer ion mobility. Meanwhile, the decoration of silver nanoparticles ensures excellent electron conductivity in the NiAl-LDH-OH nanosheets, thereby facilitating improved utilization of the active substance and achieving outstanding rate performance. The Ag@NiAl LDH-OH electrode, when prepared, demonstrates a significant increase in specific capacitance, reaching 1790 F g−1 at a current density of 1 A g−1. This represents approximately 7 times the specific capacitance of the pristine NiAl LDH electrode, with a capacity retention of 79 % even under a high current density of 20 A g−1. Moreover, the assembled asymmetric supercapacitor (ASC) attains a maximum energy density of 138.25 Wh kg−1 at a power density of 700 W kg−1, maintaining 81 % of its initial specific capacitance after 20000 cycles. This research introduces novel pathways for advancing high-energy-density SCs.

Ti3C2 Nanosheets Functionalized with Ferritin-Biomimetic Platinum Nanoparticles for Electrochemical Biosensors of Nitrite.

Nitrites widely exist in human life and the natural environment, but excessive contents of nitrites will result in adverse effects on the environment and human health; hence, sensitive and stable nitrite detection systems are needed. In this study, we report the synthesis of Ti3C2 nanosheets functionalized with apoferritin (ApoF)-biomimetic platinum (Pt) nanoparticle (Pt@ApoF/Ti3C2) composite materials, which were formed by using ApoF as a template and protein-inspired biomineralization. The formed nanohybrid exhibits excellent electrochemical sensing performance towards nitrite (NaNO2). Specifically, the Pt@ApoF catalyzes the conversion of nitrites into nitrates, converting the chemical signal into an electrical signal. The prepared Pt@ApoF/Ti3C2-based electrochemical NaNO2 biosensors demonstrate a wide detection range of 0.001-9 mM with a low detection limit of 0.425 μM. Additionally, the biosensors possess high selectivity and sensitivity while maintaining a relatively stable electrochemical sensing performance within 7 days, enabling the monitoring of NaNO2 in complex environments. The successful preparation of the Pt@ApoF/Ti3C2 nanohybrid materials provides a new approach for constructing efficient electrochemical biosensors, offering a simple and rapid method for detecting NaNO2 in complex environments.

Photoelectrochemical sensor based on AuNPs@WO3@TpPa-1-COF for quantification of DNA methylation levels.

A"signal-off" photoelectrochemical (PEC) sensing platform has been designedfor the ultrasensitive detection of DNA methylation levels and multiple methylated sites. The platform employs tungsten trioxide and TpPa-1-COF loaded by gold nanoparticle (AuNPs@WO3@TpPa-1-COF) composite material as the photoactive component and p-type reduced graphene (rGO) as an efficient quencher. The PEC signal of AuNPs@WO3@TpPa-1-COF composite is effectively quenched in the presence of p-type rGO, because p-type rGO can compete with AuNPs@WO3@TpPa-1-COF to deplete light energy and electron donors. In addition, a hybrid strand reaction (HCR) amplification strategy fixes more target DNA and then combines with rGO-modified anti-5-methylcytosine antibody to facilitate ultrasensitive DNA methylation detection. Under optimal conditions, DNA methylation can be measured within a linear concentration range of 10-14 to 10-8 M, with an exceptionally low detection limit of 0.19 fM (S/N = 3). At the same time, the platform can conduct quantitative determination of multi-site methylation, with the linear equation △I = 44.19LogA + 61.43, and the maximum number of methylation sites is 5. The sensor demonstrates high sensitivity, excellent selectivity, and satisfactory stability. Furthermore, theproposed signal-off PEC strategy was successfully employed to detect DNA methylation in spiked human serum samples, with recoveries ranging from 93.17 to 107.28% and relative standard deviation (RSD) ranging from 1.15 to 5.49%.

Preparation of activated carbon-metal nanoparticle composite materials for the catalytic reduction of organic pollutants

This work focuses on the preparation of inexpensive composite materials based on activated carbon-containing metallic nanoparticles MNPs (M = Cu, Ag, Fe). The metal nanoparticles supported on the activated carbon were prepared by ultrasound followed by chemical treatment using a reducing agent NaBH4. The obtained materials were characterized by XRD, XRF, FTIR, XPS, TGA, SEM, and TEM analysis. The different samples were tested as catalysts for the catalytic reduction of organic pollutants (MB, MO, 4-NP) in a simple and binary system in the presence of NaBH4. The results confirmed that the content of metal nanoparticles was in the following sequence 2.12%, 11.15%, and 12.13% for the materials AC-Ag, AC-Cu, and AC-Fe, respectively. According to TEM analysis, the size and dispersion of nanoparticles differ from one catalyst to another, hence the AC-Cu material exhibited good dispersion of CuNPs having ultrafine particles in the range of 4–14 nm. In order to optimize the best conditions for the reduction reaction, the effect of the nature of the catalyst, the initial concentration of NaBH4, the concentration of the pollutant, the mass of the catalyst and the nature of the pollutant were studied, and discussed. In terms of efficiency, the AC-Cu sample was the most efficient catalyst compared to AC-Fe, and AC-Ag, mainly due to the good dispersion of CuNPs on the surface of activated carbon. The recorded rate constant for the MB, MO, and 4-NP in the single system using the same operating conditions was 0.0259 s−1, 0.0218 s−1, and 0.0074 s−1, respectively. In the binary system containing MB + MO or MB + 4-NP, the AC-Cu catalyst was more selective towards the MB dye in both systems. The reuse of the AC-Cu catalyst towards the reduction of the MB dye showed good performance during five consecutive cycles without losing its efficiency.

Preparation of Inorganic Composites of Chitosan/magnesium Oxide Nanoparticle for Antibacterial Activity

Natural polymer based nanocomposites have received attention in research due their biocompatible nature and their versatile application in medical field. In the current investigation, we report the synthesize of chitosan /magnesium oxide nanoparticle (CS/MgO) composite material. The prepared sample was characterized by analytical methods such as FTIR, XRD and HRSEM.The antibacterial activity of the CS/MgO composite was evaluated. FT-IR spectral results showed the CS/MgO composite has distinctive functional groups. HR SEM images revealed that the formation of well dispersed MgO nanoparticles in CS and it is observed that the MgO nanoparticles are embedded between the functional moieties present in the chitosan which shows the good interaction between chitosan and MgO nanoparticles. The antibacterial activity of the composite was evaluated against Staphylococcus aureus and Escherichia coli. It is observed that the CS/MgO composite material showed comparatively higher inhibition against E. coli than S.aureus

Pitch Carbon‐coated Ultrasmall Si Nanoparticle Lithium‐ion Battery Anodes Exhibiting Reduced Reactivity with Carbonate‐based Electrolyte

AbstractSilicon anodes for lithium‐ion batteries (LIBs) have the potential for higher energy density compared to conventionally used graphite‐based LIB anodes. However, silicon anodes exhibit poor cycle and calendar lifetimes due to mechanical instabilities and high chemical and electrochemical reactivity with the carbonate‐based electrolytes that are typically used in LIBs. In this work, we synthesize a pitch carbon‐coated silicon nanoparticle composite active material for LIB anodes that exhibits reduced chemical reactivity with carbonate‐based electrolytes compared to an uncoated silicon anode. Silicon primary particle sizes less than 10 nm diameter minimize micro‐scale mechanical degradation of the anode composite, while conformal coatings of pitch carbon minimize the parasitic reactions between the silicon and the electrolyte. When matched with a high voltage NMC622 (LiNi0.6Mn0.2Co0.2O2) cathode, the pitch carbon‐coated silicon anode retains ≈75 % of its initial capacity at the end of 1000 cycles. Increasing the areal loading of the pitch carbon‐coated silicon anodes to realize energy density improvements over graphite anodes results in severe mechanical degradation on the electrode level, highlighting a remaining challenge to be addressed in future work.

Efficient application of new porous carbon nanoparticle composite polyaniline material in microbial fuel cells

Efficient application of new porous carbon nanoparticle composite polyaniline material in microbial fuel cells

Synthesis of Green Chitosan – Silver Nanoparticle Composite Material: Parameter Optimization and Physicochemical Characterization

In this study, response surface methodology (RSM) was carried out with four parameters: chitosan concentration, AgNO3 concentration, ascorbic acid concentration and time with the objective to obtain minimum mean particle size of silver nanoparticles (response Y). The chitosan-silver nanoparticle composite material (CTS-AgNPs nanocomposite) obtained experimentally from the optimal conditions was characterized by evaluating some of their physical-chemical properties using combined technique including visible ultraviolet spectroscopy (UV -Vis), dynamic light scattering (DLS), transmission electron microscopy (TEM), infrared spectra (IR) and X-ray diffraction. The optimal conditions were chitosan concentration of 19.2 %, silver nitrate of 26 mM, ascorbic concentration of 33 mM and time of 4.25 hours. Spherical Ag particles obtained experimentally were well dispersed in chitosan matrix with the average diameter of around 2÷8 nm with a narrow size distribution and homogeneous dispersion

Flexible Graphene-Copper Nanocomposite for Potential Wearable Electronics Applications

The demand for flexible and wearable electrochemical sensors has surged due to their low cost and portability. This study produces and characterizes low-cost and environmentally friendly flexible laser engraved graphene/Cu nanoparticles composite materials as a potential electrode for electronic applications. The electrode is fabricated by directly engraving Polyimide substrate using a CO2 laser machine to produce Laser Engraved Graphene (LEG). The electrode is then modified with copper nanoparticles via a one-step pulse electrodeposition technique to be characterized structurally, mechanically, and electrochemically using SEM, XRD, bending test, electrochemical impedance spectroscopy, and cyclic voltammetry to assess their stability and electrocatalytic activity. The laser irradiation of PI results in 3D porous graphene structure formation that increases electron transfer rate and the electrochemically active surface area. Copper deposition improves the sensitivity of LEG by its high conductivity.

Reduced Electrolyte Reactivity of Pitch-Carbon Coated Si Nanoparticles for Li-Ion Battery Anodes

Silicon-based anodes for Li-ion batteries (LIB) have the potential to increase the energy density over graphite-based LIB anodes. However, silicon anodes exhibit poor cycle and calendar lifetimes due to mechanical instabilities and high chemical reactivity with the carbonate-based electrolytes that are typically used in LIBs. In this work, we synthesize a pitch-carbon coated silicon nanoparticle composite active material for LIB anodes that exhibits reduced chemical reactivity with the carbonate electrolyte compared to an uncoated silicon anode. Silicon primary particle sizes <10 nm minimize micro-scale mechanical degradation of the anode composite, while conformal coatings of pitch-carbon minimized the parasitic reactions between the silicon and the electrolyte. When matched with a high voltage NMC811 cathode, the pitch-carbon coated Si anode retains ~75% of its initial capacity over 1000 cycles. Efforts to increase the areal loading of the pitch-carbon coated silicon anodes to realize real energy density improvements over graphite anodes results in severe mechanical degradation on the electrode level. Developing procedures to engineer the architecture of the composite silicon anode may be a solution to this mechanical challenge. Figure 1

Surface Tension and Viscosity Dependence of Slip Length over Irregularly Structured Superhydrophobic Surfaces.

A comprehensive understanding of the slip phenomenon on liquid/solid interfaces is essential for multiple real-world applications of superhydrophobic materials, especially those involving drag reduction. In the current contribution, the so-called “slip-length” on an irregularly structured superhydrophobic surface was systematically evaluated, with respect to varying liquid surface tension and viscosity. The superhydrophobic polymer–nanoparticle composite (SPNC) material used exhibits a dual-scale surface roughness and was fabricated via coating a surface with a mixture of polydimethylsiloxane solution and functionalized silica particles. A cone-and-plate rheometric device was employed to quantify the slip length. To independently study the impact of surface tension and viscosity, three types of aqueous solutions were used: sodium dodecyl sulfate, ethanol, and polyethylene glycol. Our experimental results demonstrate that a decreasing surface tension results in a decreasing slip length when the fluid viscosity is held constant. Meanwhile, the slip length is shown to increase with increasing viscosity when the surface tension of the various liquids is matched to isolate effects. The study reveals a linear relationship between slip length and both capillary length and viscosity providing a reference to potentially predict the degree of achievable drag reduction for differing fluids on SPNC surfaces.

Synthesis and application of ferromagnetic graphene oxide nanocomposite as an effective adsorbent for Clonazepam: Batch experiments, modeling, regeneration, and phytotoxicity

In this work, a ferromagnetic graphene oxide nanocomposite (mGO) was produced, characterized, and tested for clonazepam removal from water. After the nanocomposite production and characterization, adsorption tests showed that the initial pH does not influence the clonazepam removal. Clonazepam adsorption onto mGO was an extremely fast process, with equilibrium reached within the first minutes. Sips isotherm showed the best fit to the experimental data, presenting a maximum adsorption capacity of 14.81 mg g−1, indicating that the clonazepam adsorption process is favorable. Pseudo-first order was the empirical kinetic model that best fit the experimental data, with R2 > 0.99; as for the phenomenological models, both the Linear and Quadratic Driving Force models fit the data with R2 > 0.97. Moreover, the regenerative and reuse potential of the nanocomposite was analyzed, exhibiting remarkable regeneration potential, even after 5 adsorption/desorption cycles. Finally, according to the phytotoxicity tests, it was observed that the effluent treated with mGO did not present toxicity to watercress seeds, as all seeds germinated. This work stands out because it proposes a nanoparticle composite material for the viable, efficient, eco-friendly, and easy removal of an emerging contaminant from water.

Multi‐modal cell structure formation of poly (lactic‐co‐glycolic acid)/superparamagnetic iron oxide nanoparticles composite scaffolds by supercritical CO2 varying‐temperature foaming

AbstractPoly (lactic‐co‐glycolic acid) (PLGA)/superparamagnetic iron oxide nanoparticles (SPIONs) composite scaffold material was prepared by supercritical carbon dioxide varying‐temperature mode method. The multi‐modal cell structure was formed, and the mechanism was explained. The nuclei formed in the heating stage grew into large pores, while the nuclei formed in the depressurization stage grew into small pores. SPIONs caused pores to rupture and coalesce into small pores or large pores. The effects of foaming parameters, including the amount of SPIONs, saturation temperature, foaming temperature, foaming pressure, and depressurization rate on the properties of the scaffolds, were systematically studied. The results showed that the addition of SPIONs could improve the porosity and mechanical properties of the scaffold, and the obvious multi‐modal cell structure could be formed. In conclusion, by changing the foaming parameters, the PLGA/SPIONs composite scaffolds with various average diameters (11.93–790.52 μm), a wide range of porosity (62.98%–93.23%) and mechanical properties (0.38–11.12 MPa) could be obtained.

Development of a highly sensitive and selective electrochemical immunosensor for controlling of rhodamine B abuse in food samples

Here, a highly sensitive and selective electrochemical immunosensor was established for the rapid screening of Rhodamine B (Rh B) in paprika and capsicol. Rh B complete antigen was prepared and used as immunogen to obtain anti-Rh B monoclonal antibody (anti-Rh B-mAb) through cell fusion technology. A layer of cobalt hydroxide and gold nanoparticles composite material (Co(OH)2–Au NPs) was modified on the surface of screen-printed electrode (SPE) by one-step electrodeposition. Subsequently, Rh B antigen was coated on the modified SPE as coating antigen, then Rh B and anti-Rh B-mAb labeled with cerium oxide (anti-Rh [email protected]2) were overlay simultaneously. Rh B can compete with the Rh B coating antigen to combine the anti-Rh B-mAb which causing electrical signal changes. After optimization of the assembled immunosensor, the assay showed a linear range when the concentration of Rh B ranged from 0.01 ng/mL to 10000 ng/mL. The average recovery rate of spiked samples was 85.7%∼106.8%, which was in good accordance with the standard HPLC determination. The immunosensor behaves high sensitivity and selectivity, and can be used in the rapid screening of Rh B in paprika and capsicol.

Engineering Lignin-Derived Carbon–Silicon Nanocomposite Electrodes: Insight into the Copyrolysis Mechanism and Process–Structure–Property–Performance Relationships

As a renewable source, available in a large quantity, it is rewarding to find applications for lignin with high added value. We report the use of lignin in synthesizing a three-dimensional, interconnected carbon/silicon nanoparticle (C/Si NP) composite material as a low-cost replacement to conventional anode materials synthesized using expensive and toxic solvents and binders such as polyvinylidene in today’s lithium-ion battery (LIB) manufacturing process. To understand how lignin pyrolysis chemistry and processing conditions affect the structure, mechanical property, and electrochemical performance of the synthesized electrode materials, the thermochemical conversion process was, for the first time, quantitatively investigated using analytical pyrolysis–gas chromatography–mass spectrometry (GC–MS) along with a suite of other analytical tools. Results suggest that the surface bonding interaction of the C/Si NPs was evolved from pristine Si to −Si–O–C–, to −O═Si═O–, with the increase of pyrolysis temperature. The −Si–O–C– bond plays a key role in enhancing the cohesive strength and thus improving the electrochemical performance of the Si composite electrode. The pyrolysis–GC–MS can serve as a useful tool to predict the optimal pyrolysis temperature or tailor the properties of the synthesized composite electrodes by controlling the pyrolysis conditions. This study elucidates the processing–structure–property–performance relationships among lignin pyrolysis chemistry, carbon material structure and properties, and the electrochemical performance of the resulting electrode materials. Such knowledge serves as a basis for designing lignin-derived composite materials for electrochemical energy storage applications.

The investigation of the effect of nano particles on dry sliding wear and corrosion behavior of Al-Mg/Al2O3 composites

Aluminum matrix composites were extensively used as structural material as it possesses good surface properties such as wear and corrosion resistance. The practical importance of nano particles in composite materials has triggered widespread attention towards the enhancement of its properties. In this study, Al-Mg/Al2O3 (0–8 wt%) metal matrix nano composites fabricated by two step stir casting route was investigated to comprehend its wear and corrosion behaviour. The Pin-on-Disc dry sliding wear test was performed on Al-Mg/Al2O3 (0–8 wt%) by adopting Design of Experiments under the action of different contact loads and sliding distance following the ASTM G99 Standard. The experimental results conveyed that specific wear rate decreases with increase in sliding distance. Statistical analysis was performed by Taguchi’s Technique and Analysis of Variance (ANOVA) to determine the most dominating factor that influences specific wear rate for the optimum weight percentage of reinforcement. Analysis revealed adequacy with the constructed model in predicting the wear behavior of composite and unreinforced Al-Mg alloy. The corrosion behaviour of the base alloy and composites was analysed by static immersion and electrochemical assessments, by immersing prepared specimens in aqueous sodium chloride (3.5%) solution. The dependance of corrosion rate of the composites with the weight percentage of Al2O3, exposure duration and temperature of the corrosive medium was studied in detail. Corrosion test results exhibit that corrosion rate decreases with increase in weight percentage of Al2O3 particles and exposure duration, whereas it follows reverse trend with increase in corrosion medium temperature.

Effects of composite material fin conductivity on natural convection heat transfer and entropy generation inside 3D cavity filled with hybrid nanofluid

The current paper offers a numerical investigation of the combined effects of an inserted composite material fin conductivity ratio and hybrid nanofluid volume fraction on natural convection heat transfer and entropy production inside 3D cubic cavity. In this investigation, a fin is embedded at the left heated wall and is horizontally oriented toward the right cold wall, while the other surfaces are insulated from the surrounding. A broad range of parameters such as composite material conductivity ratio (1 ≤ RC ≤ 103), volumetric fraction of hybrid nanofluid (0 ≤ φ ≤ 0.05) and Rayleigh number (103 ≤ Ra ≤ 105) were considered. Obtained results reveal that the flow structure, the temperature distribution and the entropy generation rate are sensitive to nanoparticles volume fraction and composite material fin conductivity. Moreover, regardless of the latter parameter, the heat transfer is found to be enhanced with adding hybrid nanoparticles. However, the effect of increasing the conductivity on the average Nusselt number and the total generated entropy is significant only for RC > 100. The maximum Nusselt number and entropy production rate are achieved for Ra = 105, φ = 0.05 and RC = 1000.

Enhanced thermal management by introducing nanoparticle composite phase change materials for cooling multiple heat sources systems

In this paper, paraffin mixed with nanoparticles Al2O3, CuO, and multi-walled carbon nanotubes (MWCNTs) were prepared for cooling multiple heat sources. For thermal management of heat sources, performances of the composite phase change materials (PCMs) were investigated at different heating power. Enhanced performance in terms of heat sources temperature, temperature difference between two heat sources, and thermal resistance was experimentally tested and analyzed at various mass fractions of nanoparticle and various power levels. It is found that by using 1.0 wt% Al2O3 composite PCMs the minimal thermal resistance is achieved at the range from 0.63 °C/W to 0.71 °C/W for all power levels, and the heat storage and heat conduction of the presented composite PCMs are enhanced as well as the melting ratio. At 8 W power level, the temperature of the heat source 1 for 1.0 wt% Al2O3 composite PCMs decreases by 17.4% compared to that for pure paraffin.

Biomass-derived paper-based nanolignin/palladium nanoparticle composite film for catalytic reduction of hexavalent chromium

In this study, paper-based catalytic composite films were prepared by synthesizing nanolignin on a filter paper (FP) and in situ reducing Pd ions to Pd nanoparticles (NPs). Alkaline lignin (AL) NPs were controllably prepared using industrial AL via two routes: “loading and then regeneration” and “regeneration and then loading.” The NPs prepared using the former method were labelled as LAL NPs, and those prepared using the latter were labelled as RAL NPs. The as-prepared NPs were loaded into the fiber framework of the FP to obtain paper-based AL NP composite material. The results showed that the AL NPs could be successfully prepared through both routes with similar dispersity and uniformity that were improved by the presence of FP. In addition, the size range of LAL NPs (26.6–92.7 nm) was broader than that of RAL NPs (37.3–85.0 nm). The AL NPs on FP were then employed as a reducing agent for the reduction of Pd2+. The concentration of the AL solution (0.43 %–3.07 %) influenced the content of AL NPs on the FP, and a higher AL NP content resulted in higher Pd NP content. Furthermore, the obtained paper-based nanolignin/palladium nanoparticles (AL-Pd NPs/FP) composite films were used for the catalytic reduction of Cr6+. They efficiently reduced the highly toxic Cr6+ to the less toxic Cr3+, and among them, the RAL-Pd NPs/FP film with a Pd NP content of 0.18 mg/mL required only 5 min to completely catalyze the reduction of Cr6+.

Investigation into the Structural, Chemical and High Mechanical Reforms in B4C with Graphene Composite Material Substitution for Potential Shielding Frame Applications.

In this work, boron carbide and graphene nanoparticle composite material (B4C–G) was investigated using an experimental approach. The composite material prepared with the two-step stir casting method showed significant hardness and high melting point attributes. Scanning electron microscopy (SEM), along with energy dispersive X-ray spectroscopy (EDS) analysis, indicated 83.65%, 17.32%, and 97.00% of boron carbide + 0% graphene nanoparticles chemical compositions for the C-atom, Al-atom, and B4C in the compound studied, respectively. The physical properties of all samples’ B4C–G like density and melting point were 2.4 g/cm3 density and 2450 °C, respectively, while the grain size of B4C–G was in the range of 0.8 ± 0.2 µm. XRD, FTIR, and Raman spectroscopic analysis was also performed to investigate the chemical compositions of the B4C–G composite. The molding press composite machine was a fabrication procedure that resulted in the formation of outstanding materials by utilizing the sintering process, including heating and pressing the materials. For mechanical properties, high fracture toughness and tensile strength of B4C–G composites were analyzed according to ASTM standard designs. The detailed analysis has shown that with 6% graphene content in B4C, the composite material portrays a high strength of 134 MPa and outstanding hardness properties. Based on these findings, it is suggested that the composite materials studied exhibit novel features suitable for use in the application of shielding frames.