Journal of Nanoparticle Research最新文献

The present research utilizes a sol–gel auto-combustion method to produce NiFe₂O₄/g-C₃N₄ heterojunction and utilized XRD, FT-IR, SEM, EDX, HRTEM, XPS, and UV–Vis DRS analytical techniques to evaluate physical, chemical, and optical properties. Compared to other routes like one-pot hydrothermal synthesis or sol–gel for P-doped variants, this method effectively produces the desired heterojunction, contributing to enhanced photocatalytic degradation of methylene blue dye. The XRD study reveals that the produced NiFe₂O₄/g-C₃N₄ heterojunction exhibits two-phase mixing, while pure g-C₃N₄ and NiFe₂O₄ exhibit hexagonal and cubic phases, respectively. Pure g-C₃N₄ and NiFe₂O₄, and g-NiFe₂O₄/g-C₃N₄ have energy band gaps of 2.60, 1.54, and 2.49 eV, respectively. The prepared heterojunctions were used as photocatalysts to degrade the methylene blue (MB) dye. The prepared NiFe₂O₄/g-C₃N₄ heterojunction showed higher photocatalytic degradation efficacy than pristine g-C₃N₄ and NiFe₂O₄ due to greater visible light absorbance and strong heterojunction formation. The 10% NiFe₂O₄/g-C₃N₄ heterojunction showed 97.82% (0.0255 min⁻¹) degradation efficiency towards MB in 100 min, and it was 4.88 times higher than pristine g-C₃N₄ (0.0052 min⁻¹) and 7.25 times higher than pure NiFe₂O₄ (0.0035 min⁻¹) nanoparticles. The radical trapping experiment confirms that the superoxide (O₂^•−) and hydroxyl (^•OH) radicals are the key species in the MB degradation. Therefore, the Z-scheme NiFe₂O₄/g-C₃N₄ heterojunction acts as a potential photocatalyst and can be used practically for wastewater treatment.

Graphical Abstract

A real-time transmission electron microscopy (TEM) study of electron beam–induced reduction of mono- and bimetallic metal ions encapsulated within dendrimers, leading to the formation of dendrimer-encapsulated nanoparticles (DENs), is demonstrated. Traditionally, DENs are prepared by coordinating metal ions to the tertiary amines of dendrimers, followed by chemical reduction. In this work, fourth- and sixth-generation hydroxyl- and amine-terminated PAMAM dendrimers loaded with Pt²⁺ and/or Pd²⁺ ions were directly reduced under electron beam irradiation, enabling in situ observation of nanoparticle nucleation and growth with particle size ranging from 1 to 2 nm. This facile approach produces uniformly sized nanoparticles directly on TEM grids, offering promising opportunities for applications in catalysis and sensing through well-dispersed active surfaces.

To accomplish the goal of replacing fossil fuels and to report global energy crises, the primary focus of this work is the creation of highly efficient and long-lasting electrocatalysts. Here, we created MnCo₂O₄/PANI composite via a hydrothermal process which is advantageous due to its low cost, accessibility and improved catalytic activity that supports OER. The electrocatalyst’s structural, morphological and thermal characteristics were ascertained using XRD, SEM and TGA techniques. XRD examination verified the successful incorporation of the composite by showing separate peaks corresponding to both components. Additionally, according to electrochemical analysis, MnCo₂O₄/PANI composite has exceptional rate performance in an alkaline medium, exhibiting a decreased overpotential of 202 mV and a Tafel value of 39 mV dec⁻¹ at 10 mA cm⁻². The electrochemically active surface area (ECSA) was given as 910 cm². Moreover, the composite maintains its existing density for 35 h while demonstrating steady stability. Due to its extraordinary stability, rapid electron transfer mechanism and abundance of active sites, the described composite has great promise for OER. In addition to demonstrating potential for improving water oxidation by compositing techniques, this study highlights the importance of OER with the produced composite functioning as an electrocatalyst.

Coal desulfurization remains a critical environmental challenge due to stringent sulfur emission regulations and the need for cleaner energy sources. This study presents a novel magnetically separable Cu-TiO₂/Fe₃O₄ nanocomposite synthesized via an optimized sol–gel method for efficient photocatalytic oxidative desulfurization (PODS) of coal under sunlight irradiation. The heterojunction photocatalyst was systematically characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy, photoluminescence (PL), and UV–vis diffuse reflectance spectroscopy (DRS). The optimal 3.0% Cu-TiO₂/Fe₃O₄ (1:1) nanocomposite demonstrated exceptional photocatalytic performance, achieving 73.30% sulfur removal efficiency under optimized conditions: 150 mg catalyst dosage, 500 mg coal, 20 mL H₂O₂ (30 wt%), and a 5-h reaction time under direct sunlight. The enhanced photocatalytic activity is attributed to the formation of a Type-II heterojunction that facilitates efficient charge separation, reduces electron–hole recombination, and extends light absorption into the visible region (band gap: 1.90 eV). Kinetic studies revealed pseudo-first-order reaction kinetics with a rate constant of 0.278 h^⁻1. The photocatalyst exhibited excellent reusability, maintaining 68.5% of its initial activity after five consecutive cycles with excellent magnetic recovery. The photocatalytic mechanism involves the generation of hydroxyl radicals (^•OH) through both photocatalytic and Fenton-like processes, leading to the oxidation of organic sulfur compounds to polar sulfoxides and sulfones that are readily extractable. This work presents a sustainable and economically viable approach for coal desulfurization, offering significant potential for both industrial applications and environmental remediation.

In the recent years, supercapacitors with enhanced power densities and cycle stability have attracted significant attention in a variety of applications. Perovskite-based doped nanostructures were extensively studied for supercapacitors because of their exceptional conductivity, electrochemical characteristics, affordability, and environmental friendliness. Herein, SrCoO₃ and Ba-doped SrCoO₃ perovskite have been produced by hydrothermal process to investigate their electrochemical behaviour. The impact of barium doping on SrCoO₃ was determined using a number of physical and electrochemical characterisations. The X-ray diffraction study showed cubic crystal structure of Ba-doped SrCoO₃ perovskite had shown extensive surface area. The dispersion of Ba doping on SrCoO₃ nanostructures was confirmed by the scanning electron microscope (SEM) examination. Comparing to pristine SrCoO₃ (736.63 F/g), Ba-doped SrCoO₃ displayed an elevated specific capacitance (C_s) of 1231.54 F/g at 1 A/g. Additionally, the Ba-doped SrCoO₃ presented a high energy density (E_d) of 49 Wh/Kg and power density (P_d) of 280 W/kg. The improvement in electrochemical activity of Ba-doped SrCoO₃ was credited with numerous factors, including the wide ionic radius of Ba, its substantial surface area, and porous structure that permits instant ion transport. These remarkable results imply that Ba-doped SrCoO₃ nanostructures can be used in high-performance supercapacitors.

The rising contamination of aquatic environments by dyes and heavy metals poses a critical threat to ecosystems and human health, necessitating the development of effective and sustainable remediation strategies. Nano-chitosan has emerged as a frontier adsorbent due to its nanoscale surface area, abundant functional groups, biocompatibility, and environmental safety. This study provides a comprehensive systematic and bibliometric review of nano-chitosan-based adsorbents, analysing 1855 publications from 2005 to 2025 indexed in the Web of Science Core Collection. Bibliometric indicators reveal strong scientific vitality, with an annual growth rate of 21.52%, an average of 32.7 citations per article, and extensive international collaboration involving 7404 authors. Scientometric mapping identifies Asia as the leading hub, with China, India, and Iran contributing nearly 60% of global outputs. Highly cited works emphasize the development of chitosan–magnetic and oxide-based nanocomposites, which exhibit enhanced adsorption capacities exceeding 400 mg g⁻¹ for dyes and toxic metals. At the mechanistic level, the superior performance of nano-chitosan originates from its engineered nanostructure, which increases specific surface area, enhances porosity, and provides a dense array of reactive functional groups. This structural optimization facilitates electrostatic and chemical interactions while simultaneously improving mass transfer, leading to faster adsorption kinetics, higher equilibrium uptake, and robust recyclability in multifunctional wastewater treatment composites. By combining systematic insights with bibliometric evidence, this review positions nano-chitosan as a cornerstone material for next-generation water purification and outlines future research pathways for scalable, eco-friendly solutions.

Topical mupirocin (MP) remains clinically important for managing skin infections, yet its therapeutic efficacy is constrained by poor dermal permeation and the rapid emergence of bacterial resistance. To address these limitations, we developed and systematically evaluated a novel liposome-in-hydrogel nanofilm composed of mupirocin-loaded liposomes embedded in a crosslinked poly(vinyl alcohol)/poly(ethylene glycol) polymeric matrix. MD simulations revealed that mupirocin incorporation did not destabilize the lipid bilayer, while preferential interactions with POPE lipids over DPPC were observed. Liposomes prepared via thin-film hydration exhibited nanoscale dimensions (SEM ~ 147 nm; DLS ~ 249 nm), a stable negative surface charge (− 46 mV), high encapsulation efficiency (99%), and substantial drug loading (33%). Embedding these vesicles into the hydrogel matrix yielded a mechanically stable nanofilm, with SEM and FTIR confirming homogeneous liposome integration and reduced pore size relative to the unloaded control. The formulation prolonged drug release, extending 70% cumulative release to ~ 24 h versus ~ 4 h in drug-only hydrogel. Ex-vivo permeation studies across murine skin demonstrated ~ 50% higher cumulative delivery compared with unreinforced films. Mechanical testing indicated increased tensile strength and stiffness, supporting its potential as a durable topical dressing. Biological assays confirmed preserved antimicrobial activity against methicillin-resistant Staphylococcus aureus with inhibition zones (~ 34–35 mm) equivalent to commercial mupirocin discs, alongside high fibroblast viability (89–92%) evidencing cytocompatibility. In summary, this study demonstrates that the liposome-in-hydrogel nanofilm is a promising biocompatible carrier that sustains mupirocin release, enhances dermal penetration, and maintains antimicrobial efficacy.

We aim to demonstrate the gold nanoparticle formation on silicon substrates by a time-consuming furnace process and a ns-short laser-induced process as methods that can be performed under ambient conditions. The properties of the particles are shown by means of electron microscopy and X-ray diffraction. We have found differences that suggest solid-state dewetting and liquid-state dewetting depending on the incorporated thermal energy. The short thermalization time of the laser process allows us to produce round-shaped polycrystalline nanoparticles. The nanoparticle formation by laser is dependent on the pulse energy and the pulse number. As a function of temperature from 300 to 1100 °C in a furnace, applied to thin gold films from 5 to 20 nm, the layers show complete dewetting of the substrate combined with the forming of nanoparticles with facette-like surfaces. Both methods show an improvement in the (111) texture with a small energy input up to the melting temperature of gold at 1060 °C compared to the original gold layer. However, with further increasing energy, the texture decreases again and falls below the level of the original layer. The particle size distributions, the crystallite sizes, and the intensity ratio of (111) and (002) reflexes are discussed.