Journal of Nanoparticle Research最新文献

This paper is a fundamental exploration of the dynamic area of nanocatalysis, offering a detailed analysis of recent advancements and practical applications. Tailored for researchers and professionals, this article begins with a historical overview, emphasizing nanocatalysis’ pivotal role in contemporary science and industry. It delves into foundational principles, covering nanoparticle synthesis, characterization, surface chemistry, and reactivity mechanisms at the nanoscale. Advanced sections explore the design of nanomaterials for catalysis, hybrid catalyst synthesis, and the integration of computational approaches. Mechanistic insights are presented through a detailed examination of reaction pathways and cutting-edge spectroscopic techniques. Practical applications span energy conversion, sustainable synthesis, and environmental remediation, with illustrative case studies. The article concludes by addressing current challenges, outlining future perspectives, and highlighting emerging trends, making it an essential guide for those navigating the multifaceted landscape of nanocatalysis.

This research presents a non-traditional method for surface modification. a Cu₂O/CuO heterostructure was prepared on Cu foil by a dielectric barrier discharge (DBD) plasma and used as a photocathode for photoelectrochemical (PEC) water splitting. Cu₂O/CuO heterostructure was prepared at 1 min, 3 min, and 6 min exposures of the Ar/O₂ gas mixture using DBD plasma, followed by the calcination process at 200 °C for 2 hours. The samples were applied toward PEC water splitting. The samples' X-ray diffraction (XRD) pattern confirmed the cubic phase of Cu₂O and the monoclinic phase of CuO. The field emission scanning electron microscope (FE-SEM) images show that the sample after 1 min of plasma exposure consists of a broccoli-like microstructure, and by increasing the duration time to 3 min and 6 min, the microwire structure was prepared. The presence of minuscule nanoparticles on the surface of all microstructures leads to an elevation in aspect ratio and charge carrier density, resulting in improved performance in photoelectrochemical (PEC) properties. The highest photocurrent of 6.53 mA/cm² at 1.23 V vs. reversible hydrogen electrode (RHE) was recorded for Cu₂O/CuO heterostructure prepared at 3 min exposure plasma under AM 1.5G irradiation. A longer exposure time of DBD plasma causes more thickness and increases the recombination of charge carriers, which decreases the photocurrent density to 4.32 mA/cm² at 1.23 V_RHE. This study demonstrates the development of a Cu₂O/CuO heterostructure on Cu foil with a high aspect ratio as a promising method for enhancing the photoresponse of the Cu₂O/CuO photocathode in the context of photoelectrochemical (PEC) water splitting.

In this work, silver ferric oxide (AgFeO₂) nanoparticles have been successfully synthesized using the co-precipitation method and characterized with various techniques. Highly porous, grain-like AgFeO₂ nanoparticles were prepared. Furthermore, this work explores and for the first time proposes the possibility of using low-cost AgFeO₂ nanoparticles with a delafossite structure for the low-temperature detection of nitrogen dioxide (NO₂) gas. AgFeO₂ nanoparticle powder was characterized using X-ray diffraction (XRD). It discloses the delafossite structure indicating the presence of both rhombohedral and hexagonal structures having an average crystallite size of 47 nm. The field emission scanning electron microscopy (FE-SEM) and energy-dispersive spectroscopy (EDS) study give the idea about dense distribution nanoparticles and confirm the elemental composition of AgFeO₂, respectively. Transmission electron microscopy (TEM) shows that grain-like nanostructures have a particle size in the range of between 50 and 80 nm. The specific surface area was calculated by Brunauer–Emmett–Teller (BET), and it was found to be 31.9353 ± 0.1551 m²/g. It is found that the AgFeO₂ gas sensor shows high selectivity to words NO₂ gas at 8 ppm gas concentration at an operating temperature of 50 °C.

In this paper, we examine the application of density functional theory (DFT) to determine the structural and optoelectronic properties of the tetragonal monochalcogenide TlSe, in order to assess its suitability for use in optoelectronic devices, photovoltaics, etc. These calculations are carried out using the full-potential linearized augmented plane wave (FP-LAPW) method, implemented in Wien2k software. The monochalcogenide compound TlSe adopts a tetragonal structure with I4/mcm space group symmetry (No. 140). We determined the ground-state values by calculating the total energy as a function of volume, relaxing the atomic positions for each volume, in order to minimize both the strength and the c/a ratio. Equilibrium structural parameters are derived from the internal structure parameters by fitting the total energy versus volume results with the Birch-Murnaghan equation of state. We studied the electronic properties using two approaches, GGA and TB-mbj. The latter approach gave an energy gap of 0.49 eV, close to the experimental value, which led us to adopt the TB-mbj approach in calculating optical properties such as the complex dielectric function (mathrmvarepsilonleft(mathrmomegaright)), complex refractive index (mathrm Nleft(mathrmomegaright)), optical reflectivity (mathrm Rleft(mathrmomegaright)), energy loss function (mathrm Lleft(mathrmomegaright)), optical absorption (mathrmalphaleft(mathrmomegaright)) and optical conductivity (mathrmsigmaleft(mathrmomegaright)).

In this work, a simple colorimetric method based on the gold nanoparticles (AuNPs) using its localized surface plasmon resonance (LSPR) was proposed for the simultaneous determination of tamsulosin (TAM) and dutasteride (DTS) in pharmaceutical formulation. The aggregation of citrate-capped AuNPs was observed in the presence of TAM and DTS, which led to a change in color from red to gray. Also, the absorbance was shifted from 524 to 674 nm. The formation and size of synthesized AuNPs before and after aggregation were evaluated by transmission electron microscopy (TEM) and dynamic light scattering (DLS), which were found to be 11.49 and 122.1 nm, respectively. The colorimetric method was validated in the concentration range of 50–200 μg/L, where it revealed good linearity (R² = 0.9958 for TAM and R² = 0.9912 for DTS). The limit of detection (LOD) and limit of quantitation (LOQ) were found to be 21.08, 21.82 μg/L and 63.90, 66.12 μg/L for TAM and DTS, respectively. Radial basis function neural network (RBF-NN) and fuzzy inference system (FIS) were coupled with this approach for the simultaneous estimation of both components. The mean recovery percentage of the RBF model was higher than 99.99% for both components, as well as root mean square error (RMSE) values were 3.69 × 10⁻¹³ and 1.75 × 10⁻¹³ for TAM and DTS, respectively. In the FIS model, the mean recovery was 99.15% and 101.76% for TAM and DTS, respectively, while RMSE was lower than 3.2. These methods were compared with high-performance liquid chromatography (HPLC) through an analysis of variance (ANOVA) test. This colorimetric method can be an appropriate choice for the determination of drug contents in pharmaceutical and biological samples.

The discharge of toxic industrial effluents into freshwater has a significant impact on both humans and aquatic lives, which needs to be addressed on an urgent basis. SnO₂, a wide bandgap material possesses good photocatalytic properties, which can be exploited to degrade organic pollutants. However, there is a need to develop an appropriate strategy to decrease its bandgap and minimize the recombination of charge carriers. For this purpose, we are reporting the synthesis of SnO₂/SnSe composites by wet chemical process in various ratios. The as-synthesized samples were analyzed through various characterization techniques. The X-ray diffraction (XRD) patterns confirmed the successful synthesis of tetragonal rutile SnO₂ and orthorhombic structure of SnSe. The average crystallite size varied between 25 and 35 nm. UV–visible spectroscopy (UV–vis) confirmed that the bandgap of SnO₂ and SnSe was 3.63 eV and 1.21 eV, respectively, whereas the bandgap of composites ranged from 3.47 to 3.03 eV. The FTIR spectrum exhibited absorption peaks at 745 cm⁻¹, 1113 cm⁻¹, and 1381 cm⁻¹ due to the Sn–O–Sn bond and Sn–OH bond vibrations. Whereas the absorption observed at 665 cm⁻¹ is associated with Se–O bond vibration. Raman spectroscopy revealed the bands at 629 cm⁻¹ and 767 cm⁻¹ for the rutile structure of SnO₂ and bands at 75 cm⁻¹, and 152 cm⁻¹ are characteristic of SnSe. Scanning electron microscopy (SEM) illustrated the formation of irregular-shaped agglomerated nanoparticles of the prepared materials. Photodegradation of methylene blue (MB) revealed that the composite containing 78% SnO₂ and 32% SnSe (denoted as SS-4) was highly an highly effective catalyst and degraded 97.1% of MB in 120 min. The reaction kinetics of the prepared photocatalysts satisfied the Langmuir–Hinshelwood model.

The design of nanostructures based on peptides has attracted wide attention, especially the design of new nanomaterials with higher levels of multifunctional ability is gradually needed. Patent layout allows to identification of related technologies and trends. To reveal the development of global polypeptide nanotechnology in the field of medical application, this paper uses the text mining technology based on patent semantic content to extract the contained knowledge from the patent data set from 1978 to 2023 retrieved from incoPat database and combines the knowledge network with the theme evolution. The hot topics were obtained, and the main technical topics of improving the function of nanomaterials modified by polypeptide were analyzed: the nanointelligent delivery system modified by polypeptide improved the response to stimuli, the transfection rate of gene therapy was improved, the targeting and cell penetration of tumor therapy were improved, the diagnostic sensitivity and biocompatibility were improved, and the detection time of sensors was improved. The research shows that most nanotechnology based on polypeptide is used in medicine to optimize the effect of chemotherapy for tumor treatment. The development of gene therapy is developing rapidly, and technologies such as diagnosis and sensors are emerging, which seems to be very promising. They may hide great potential and represent the field of opportunity research. Most importantly, the technologies related to polypeptide-modified nanostructures are still rapidly developing, and this trend is expected to continue in the next few years.

The use of zinc oxide nanoparticles (ZnO NPs) is part of the search for strategies to achieve food security in a sustainable way. However, its usefulness in crop production has not been sufficiently demonstrated and its consequences on soil microorganisms are still unclear. In this study, the combined effect of ZnO NPs and inoculation with arbuscular mycorrhizal fungi (AMF) on growth, yield, and antioxidant capacity of Capsicum chinense Jacq. was analyzed. Additionally, the effect of ZnO NPs on mycorrhizal colonization and dependency was evaluated. For this purpose, a greenhouse experiment was performed in which 0, 1.2, 12, and 240 mg kg⁻¹ of ZnO NPs were applied to mycorrhized and non-mycorrhized plants. Fresh and dry biomass, fruit yield, and antioxidant capacity were quantified, as well as colonization percentage and mycorrhizal dependency. It was found that the ZnO NPs 240 mg kg⁻¹ dose increased plant fresh aerial biomass and antioxidant capacity, while all ZnO NPs doses increased fruit biomass. On the other hand, the 12 and 240 mg kg⁻¹ doses decreased mycorrhizal dependency, but no ZnO NPs dose affected mycorrhizal colonization. In turn, the inoculation with AMF increased all growth and fruit yield variables, but not the antioxidant capacity of habanero pepper. Besides, an antagonistic effect on fruit biomass was found between the addition of ZnO NPs and the inoculation with AMF. These results demonstrate that the application of ZnO NPs within the dosage range of 1.2 to 240 mg kg⁻¹ enhances the yield of C. chinense without impacting its mycorrhizal interaction.

Clinical failure of dental resin-composite restorations is mainly due to bacterial-mediated secondary caries formation. Therefore, the development of a flowable resin-composite material having inherent antibacterial properties is crucial to enhance the durability of dental restorations. Herein, dental flowable resin-composite material was modified with chlorhexidine-loaded mesoporous silica nanoparticles (CHX-MSN) to induce in situ antibacterial properties against S. mutans. Mesoporous silica nanoparticles loaded with chlorhexidine (CHX-MSN) were formulated and characterized for drug-loading/encapsulation efficiency, morphology by electron microscopy, and infrared spectral analysis. CHX-MSN were incorporated into the flowable composite material at different concentrations of 1, 5, and 10% (w/w) and examined at two time points (baseline and 3 months in artificial saliva). The CHX-MSN modified composites exhibited an initial CHX release burst followed by a steady release up to 30 days. The antimicrobial efficacy of the modified composites was evaluated by crystal violet assay, MTT assay, and confocal laser scanning microscopy. In addition to measuring the degree of conversion and cytotoxicity, the mechanical properties were characterized by surface microhardness and flexural strength. The modified composites demonstrated a significant increase in antimicrobial properties compared to the unmodified control (p < 0.05) which is dependent on the concentration of the CHX-MSN nanoparticles. In addition, the modified composites possessed acceptable biocompatibility without adversely affecting mechanical properties and degree of conversion up to 5% addition of CHX-MSN nanoparticles. This study introduced a protocol to develop resin-based flowable dental composite material having superior antibacterial property against cariogenic biofilms aiming for enhancing clinical longevity of dental restorations.

Graphical Abstract

In this study, the structural, electronic, and optical properties of pristine graphene and graphene doped/co-doped with (N, Si) atoms are examined using a first-principles investigation. However, pristine graphene is characterized by a unique electronic structure known as the zero band gap (Eg = 0 eV), and this gap was opened up after the addition of N and Si substitutions, where it became 0.2, 0.21, and 1.38 eV for graphene doped with nitrogen, silicon and double doped with both (N, Si), respectively. For the band gap and the density of states, many parameters have been studied such as the complex dielectric function, conductivity, absorption spectra, loss function, and refractive index. The absorption curve shows two sharp peaks for all structures, where their intensities become lower and shift slightly towards lower energy after doping graphene with N, Si, and N-Si, indicating that this doping introduces additional energy states in the graphene band structure, making the transition between states easier to achieve.