Uniform Distribution Of Nanoparticles Research Articles

Green synthesis of Ag/V2O5 and Ag/V2O5-curdlan nanocomposites from Sargassum latifolium extract for enhanced antimicrobial and antioxidant activities.

The emergence of clinic-isolated bacteria and their ability to develop resistance mechanisms against conventional antimicrobials highlights the urgent need for novel, sustainable antimicrobial agents. This study explores the synthesis of Ag/V2O5 nanocomposites (NCs) using Sargassum latifolium extract, which is incorporated into a curdlan biocompatible matrix. The developed nanocomposites are evaluated for their antioxidant and antimicrobial activities, with a particular focus on their effectiveness against pathogenic bacteria. The applied method in this work combines green synthesis with the process of uniform distribution of nanoparticles to a biocompatible polymer, which is a way forward towards the design of efficient biocompatible antimicrobial systems. The Ag/V2O5 nanoparticles prepared with green synthesis were characterized by UV-Vis absorption, FTIR, XRD, SEM, EDX, zeta potential, DLS, and TEM. It has also been established that the antimicrobial property of the curdlan matrix has been enhanced with the addition of Ag/V2O5 nanoparticles in the incorporated curdlan composites. Ag/V2O5-curdlan also showed significantly enhanced antimicrobial activity against Gram-negative bacteria and Gram-positive bacteria thus implying enhanced antimicrobial action of the prepared nanocomposite by increasing the size of the bacterial zone of inhibition from 14.0 to 18.0 mm. Besides, the curdlan NC in the presence of Ag/V2O5 demonstrated an even lower value of MIC against Rhizoctonia solani (140.156 μg/mL) in comparison with Ag/V2O5 NC (226.413 μg/mL) thus predicting Augmented antifungal activity. Through performing TEM analysis, we have observed significant morphological changes in R. solani strain when the Ag/V2O5-curdlan NC was used. However, the Ag/V2O5-curdlan NC had a notably high antioxidant activity with IC50 of 0.302 mg/mL to DPPH radical scavenging assay. These results reaffirm the enhancement in antimicrobial properties when Ag/V2O5 and curdlan work together and agree with the objective of this work to propose novel and worthwhile nanomaterials for potentially applicable areas like food packaging or agriculture with insignificant harm to the environment.

Sustainable and Flexible Surface-Enhanced Raman Scattering Transducer: Gold Nanoparticle-Bacterial Cellulose Composite for Pesticide Monitoring in Agrifood Systems

Functionalized plasmonic nanostructure platforms are widely used for developing optical biosensors and SERS assays. In this work, we present a low-cost and scalable surface-enhanced Raman scattering (SERS) system based on an innovative optical transducer comprising gold nanoparticles (AuNPs) embedded in nano-fibrillated bacterial cellulose (BC). The AuNPs@BC composite leverages the unique nanofibrillar architecture of bacterial cellulose, which provides a high surface area, flexibility, and uniform nanoparticle distribution, enabling the formation of numerous electromagnetic “hot spots”. This structure excites localized surface plasmon resonance (LSPR), as demonstrated by a bulk sensitivity of 72 nm/RIU, and supports enhanced Raman signal amplification. The eco-friendly and disposable AuNPs@BC platform was tested for agrifood applications, focusing on the detection of thiram pesticide. The system achieved a detection limit of 0.24 ppm (1 µM), meeting the sensitivity requirements for regulatory compliance in food safety. A strong linear correlation (R2 ≈ 0.99) was observed between the SERS peak intensity at 1370 cm−1 and thiram concentrations, underscoring its potential for quantitative analysis. The combination of high sensitivity, reproducibility, and environmental sustainability makes the AuNPs@BC platform a promising solution for developing cost-effective, flexible, and portable sensors for pesticide monitoring and other biosensing applications.

Improving Photocatalytic Hydrogen Production over Pd Nanoparticles Decorated with g-C3N5 Photocatalyst

A uniform distribution of Pd nanoparticles on g-C3N5 layers is achieved through wet-chemical reduction (Pd/g-C3N5-EG). Pd/g-C3N5-EG demonstrates superior hydrogen production yield compared to heterojunctions synthesized via photoreduction (Pd/g-C3N5-PR), attributed to improved metal–support interaction. Pd/g-C3N5-EG demonstrates an average hydrogen evolution rate of 891.304 µmol g−1 h−1, representing a 7.8-fold increase over Pd/g-C3N5-PR and a 34.5-fold increase over bare g-C3N5. Pd/g-C3N5-EG also maintains its hydrogen production capability after five recycling cycles, with only a slight decrease in efficiency.

Removal of Tetracycline Antibiotic as a Hospital Waste by pH‐Sensitive Degradable Composite Hydrogel Using Fenton‐Like System

ABSTRACTFenton‐like hydrogels crosslinked with imine bond were prepared for the removal of tetracycline. Initially, the oxidation process of carboxymethyl cellulose (CMC) was performed, and it was named OX‐CMC. The confirmations were then obtained using NMR and FTIR analyses. The degree of CMC oxidation was investigated in relation to reaction time, and optimal time of 4 h was selected. In the second part, a pH‐sensitive hydrogel with imine bond was prepared from the crosslinking reaction between OX‐CMC and chitosan. The formation of the hydrogel through imine crosslinking was confirmed by FTIR spectroscopy. By increasing ratio of OX‐CMC to chitosan, the swelling rate for the hydrogel decreased. Turbidity measurements showed that a higher OX‐CMC to chitosan weight ratio resulted in slower hydrogel degradation in acidic environments. In the third part, Fe3O4 nanoparticles with concentrations of 5 and 10 wt% were incorporated into the hydrogel structure. TEM studies revealed a spherical morphology and uniform distribution of nanoparticles within the hydrogel network. SEM images revealed a porous structure which composed of interconnected pores in the hydrogel. The results of UV–visible spectroscopy indicated that the degradation of magnetic hydrogels would augment as magnetic nanoparticle content increases, pH decreases, and the hydrogen peroxide content increases.

Oxide distribution in PBF-LB/M-processed ODS steel: Effects of ball milling and dielectrophoretic deposition in powder production

This study provides key insights into the critical role of nanoparticle distribution in oxide dispersion-strengthened (ODS) powders for laser powder bed fusion (PBF-LB/M). A comparative analysis of mechanical (ball milling, BM) and liquid-based (dielectrophoretic deposition, DD) additivation methods was conducted to produce ODS feedstocks by integrating 1 vol.-% yttria (Y2O3) nanoparticles into Fe20Cr metal powder. ODS materials enhance high-temperature strength and creep resistance by dispersing fine, stable oxide particles within a metal matrix. This makes the precise size and distribution of nanoparticles crucial in the final bulk material. Powder characterisation shows that while both methods produce powders suitable for high-density parts, the DD method achieves higher uniform nanoparticle distribution, with smaller average particle sizes (74 nm) and interparticle distances (826 nm). In contrast, longer milling durations resulted in slightly larger particle sizes (77 nm) and distances (790 nm), while shorter milling times produced even larger nanoparticles (108 nm) with greater interparticle distances (1114 nm). These results suggest that DD offers advantages in optimising the distribution of oxide nanoparticles to enhance the strengthening effects in high-temperature applications.

Solar Assisted Mitigation of Chloramphenicol and H2 Evolution Using CuNi Alloy Nanoparticles on h-BN Doped g-C3N4: A Comprehensive Approach Combining Synchrotron and DFT Analysis.

A simple one-step deposition-precipitation method was used to synthesize highly active and well-defined CuNi alloy bimetallic nanoparticles supported on h-BN/g-C3N4. The nanocomposite was applied for hydrogen gas evolution via seawater splitting and photocatalytic chloramphenicol (CHP) removal. Through TEM and synchrotron studies, the formation of CuNi alloy and uniform distribution of CuNi bimetallic nanoparticles on the h-BN/g-C3N4 surface was observed. The EXAFS analysis verified the successful formation of the alloy, while the XPS and XANES spectra showed that the bimetallic nanoparticles are in a metallic state. Additionally, XANES revealed nanoparticle distortion upon interaction with the support, confirming the effective formation of the nanocomposite. The nanocomposite achieved a maximum hydrogen evolution rate of 3658.9 μmol g-1 h-1 for 5 wt % CuNi(3:1)/h-BN/g-C3N4, outperforming CuNi(3:1) nanoparticles and pristine g-C3N4 by 1.82 and 4.31 times, respectively. Additionally, it degraded chloramphenicol with a rate constant (kapp) of 0.018 min-1. Optical and electrochemical analysis revealed enhanced charge mobility, extended lifetime, improved photostability, and superior photoresponse. X-ray absorption spectroscopy (XAS) and density functional theory (DFT) calculations attributed the performance to the synergy between the bimetallic nanoparticles and the h-BN/g-C3N4 sheet. DFT calculations demonstrated the effective breakdown of chloramphenicol and the promotion of hydrogen gas evolution, aligning with experimental observations. Cytotoxicity of CHP post-treatment was analyzed using Drosophila melanogaster (fruit fly) and the Oregon-R strain of D. melanogaster.

Facile preparation of wood-based Janus membrane by hydrothermal ZnO with photoregulated wettability

This study developed a functional Janus wood (JW) membrane with designed wettability gradient through simple modification of balsa wood and evaluated its performance in liquid transport, fog collection, and oil–water separation. Zinc oxide (ZnO) nanoparticles were uniformly loaded into the wood membrane via vacuum impregnation and hydrothermal crystal growth, creating a stable hydrophobic layer. The single-side UV irradiation further induced the hydrophilic-hydrophobic gradually transitional structure. Uniform ZnO nanoparticle distribution was confirmed by SEM, XRD, XPS analyses, and so on. Increased surface area and targeted wettability differences were also detailly verified. UV treatment transformed ZnO to Zn(OH)2 altering the wettability transformation. The JW membrane demonstrated stable wettability under various pH, salinity, and abrasion conditions, with over 98.7% fog collection efficiency and reduced water evaporation. It also achieved over 99.6% separation efficiency for light and heavy oils with high flux and reusability. Due to its simple preparation process, cost effective, and excellent performance with durability, the JW membrane shows strong potential for applications in commercial environment. The study provided scenarios and solutions for multi-functional applications of sustainable wood and offered a new consideration for the design and preparation of Janus membranes.

Deep P‐C Interface Reconstruction for High‐Performance Potassium Storage

AbstractPotassium‐ion batteries (PIBs) capable of achieving full charge in minutes, or even in seconds, while maintaining high energy densities, are highly desirable for practical applications. However, significant challenges exist in developing electrodes that can sustain both high capacity and rapid charging rates. Conventional phosphorus‐carbon composites, limited by the intrinsic common carbon materials structure, often fail to prevent the edges reconstruction of black phosphorus (BP), thereby limiting its potential advantages as a high‐capacity, high‐rate anode. This study addresses these challenges by grafting BP onto a super‐porous carbon (SPC) framework to serve as an anode for potassium storage. The large number of open pores in SPC ensures the uniform distribution of BP nanoparticles in this carbon matrix, realizing the complete potassiation reactions and uniform volumetric strain dispersion. The abundant defects significantly promote the phosphorus‐carbon reconstruction between edge carbon atoms and edge phosphorus atoms, effectively inhibiting the P‐P edge reconstruction of BP to ensure open edges for rapid K+ diffusion. As a result, the composite exhibits excellent performance in potassium storage, demonstrating superior capacity, charging rates, and cycling durability. This research provides a new insight into enhancing BP‐base anodes, offering favorable guidance for the development of high‐performance materials.

MoOX–Graphene Nanocomposite Electrode As a High-Performance Bifunctional Electrocatalyst for All Vanadium Redox Flow Battery

As one of the most promising electrochemical energy storage systems, vanadium redox flow batteries (VRFBs) have received increasing attention owing to their attractive features for large-scale storage applications. However, their high production cost and relatively low energy efficiency still limit their feasibility. One of the critical components of VRFBs that can significantly influence the effectiveness and final cost is the electrode. Therefore, the development of an ideal electrocatalyst with low cost, high electrical conductivity, large active surface area, good chemical stability, and excellent electrochemical reaction activity toward the VO2+/VO2 + and V2+/V3+ redox reactions is essential for the design of VRFBs. Extensive research has been carried out on electrode modification routes for VRFBs to improve the energy density and overall performance for large-scale applications. In the present work, we reported the successful preparation of low-cost MoOX–reduced graphene oxide nanocomposite (MoOX–rGO) acts as the electrode material for all-vanadium redox flow battery (VRFB). MoOX–rGO composite exhibits excellent electrocatalytic redox reversibility for V3+/V2+ and VO2 +/VO2+ and higher anodic and cathodic peak currents than those of other individual MoOX and rGO samples. The voltage efficiency of the VRFB using the optimized MoOX–rGO nanocomposite electrode at 80 mA cm−2 is 82.14%, which is 4.23% and 13.56% higher than the VRFBs using the rGO-coated graphite felt electrode and the graphite felt electrode, respectively. It still shows the voltage efficiencies of 73.83% and 68.50% at 120 mA cm−2 and 140 mA cm−2, respectively, but other samples have no effective discharge. This improvement is attributed to the uniform distribution of MoOX nanoparticles on the rGO surface, avoiding the restacking of the rGO sheets and suppressing nanoparticle aggregation, which might increase the effective surface area and improve mass transport at the electrode-electrolyte interface. Furthermore, oxygen vacancies on MoOX, the high electrical conductivity of rGO, and the high content of oxygen functional groups act as active sites for the vanadium ion redox reaction. References W. Bayeh, G-Y. Lin, Y-C. Chang, D.M. Kabtamu, G-C. Chen, H-Y. Chen, K-C. Wang, Y-M. Wang, T-C. Chiang, H-C. Huang and C-H. Wang, ACS Sustain. Chem. Eng., (2020).Zhou, Y. Shen, J. Xi, X. Qiu and L. Chen, ACS Appl. Mater. Interfaces, 8, 15369- 15378 (2016).M. Kabtamu, J-Y. Chen, Y-C. Chang and C-H. Wang, J. Power Sources, 341, 270-279 (2017).Amini, J. Gostick and M.D. Pritzker, Adv. Funct. Mater., 30, 1910564 (2020).M. Kabtamu, J-Y. Chen, Y-C. Chang and C-H. Wang, J. Mater. Chem. A, 4, 11472-11480 (2016).

Enhanced photocatalytic degradation of methylene blue dye by ZnO nanoparticles: Synthesis, characterization, and efficiency assessment

AbstractThe release of synthetic dyes from the textile industry into aquatic environments poses a significant threat due to their carcinogenic properties. Photocatalytic treatment methods have emerged as efficient alternatives for addressing dye contamination in water. In this study, we investigate the photocatalytic degradation of methylene blue dye using zinc oxide (ZnO) nanoparticles under UV irradiation. ZnO nanopowders were synthesized via the sol–gel process and characterized for their structural, optoelectronic, optical, and chemical properties to demonstrate their suitability for photocatalytic degradation. Photocatalytic experiments were conducted using pure ZnO nanoparticles as catalysts, resulting in a degradation efficiency of 72.3% for methylene blue. Characterization techniques, such as X‐Ray Diffraction (XRD), Energy Dispersive X‐Ray Analysis (EDX), Scanning Electron Microscopy (SEM), and FTIR confirmed the presence of ZnO bonds and the uniform distribution of nanoparticles with small grain sizes. Density Functional Theory (DFT) calculations using the modified Becke–Johnson (mBJ) approximation revealed a direct band gap of 3 eV for ZnO, confirming its potential for photocatalysis. These findings underscore the enhanced photocatalytic activity of ZnO nanoparticles, highlighting their potential for use in photocatalysis applications. This study contributes to the growing body of research aimed at addressing environmental challenges associated with dye contamination in water.

In vitro sustained release modeling and antimicrobial properties of the Persian gum-based bio-nanocomposite loaded with electrosprayed gliadin containing cinnamon essential oil

This study aimed to produce bio-nanocomposites based on Persian gum-starch using electrosprayed gliadin nanoparticles (EGNPs) containing cinnamon essential oil (CEO) to increase the shelf life of rainbow trout fillets and to model its in vitro release. The CEO with 5, 10, and 15 % w/w were loaded in the EGNPs. The EGNPs containing 10 % w/w CEO had the highest encapsulation efficiency (92.85 % ± 1.01 %) and uniform morphology. Field emission scanning electron microscopy showed that 10 % w/w EGNPs in the Persian gum-based films was accompanied by a uniform distribution of nanoparticles in the bio-nanocomposite. However, higher levels of nanoparticles (15 % w/w) were associated with forming local aggregates on the surface of bio-nanocomposites. Fourier transform infrared analysis confirmed the successful encapsulation of CEO in the EGNPs and the successful placement of nanoparticles in the matrix. By integrating 10 % w/w of electrosprayed nanoparticles, the mechanical properties of bio-nanocomposites were significantly reinforced. The Peleg model was the best model describing the release behavior of the CEO from the designed structures, and the dominant mechanism affecting its release was the Fickian diffusion. Using bio-nanocomposites containing 10 % w/w of EGNPs containing CEO suppressed the growth of microorganisms and increased the shelf life of coated fillets.

НАНОТЕХНОЛОГИИ В ПРОИЗВОДСТВЕ СТРОИТЕЛЬНЫХ МАТЕРИАЛОВ: ТЕОРЕТИЧЕСКОЕ ИССЛЕДОВАНИЕ

The modern stage of development of the construction industry begins to apply nanotechnology. Nanotechnology makes it possible to create a wide range of construction materials. This is done by controlling both the external and the internal structure of materials. The use of nanotechnology leads to the creation of new composite materials with truly unique characteristics. Developments of scientists in the field of creation of building materials based on nanotechnology are less applied on an industrial scale than in other spheres of national economy. In this study nanotechnology is considered as a set of techniques, chemical and physicochemical methods aimed at synthesizing in the volume or on the surface of the material structures having at least one direction of nanoscale. The methodological basis of the work is the analysis of literature data on the use of nanotechnology in building materials science. The result of the study was the identification of the synergistic effect of nano- and ultradisperse particles on the production of new building materials using nanotechnology. Obtaining high-quality nanostructured material containing nano- and ultradisperse particles of different nature is associated with significant difficulties. Their introduction in the form of powder into cement or other binding matrix is a very complicated process. Nano- and ultradisperse particles are prone to ag-glomeration. To achieve uniformity of their distribution in the volume of material is a difficult task, which is the subject of many studies. In the process of analyzing the literature data, the authors came to the conclusion that it is necessary to apply various technological methods for uniform distribution of nanoparticles in the volume of the material. This approach will allow to increase physical-mechanical, organoleptic and other properties of building materials.

Synthesis of Chitosan-Agar immobilized NiO-MgO bionanocomposites and their photocatalytic application towards toxic azo dye

In this study, NiO-MgO nanoparticles (NiMg NPs) were synthesized and incorporated into a biopolymer blend of chitosan (CTS) and agar agar gum (AA), forming the novel CTAG@NiMg bionanocomposite (BNC). Structural analysis revealed a crystal size of 19 nm and a direct band gap of 2.75 eV, indicating strong potential as a UV-active photocatalyst. TEM images confirmed uniform nanoparticle distribution with an average size of 25 nm. The elemental composition, verified by EDX spectra, showed weight percentages of C (21.32 %), O (31.47 %), Ni (35.39 %), and Mg (11.82 %). The CTAG@NiMg BNC demonstrated outstanding photocatalytic degradation of methyl orange (MO) dye, achieving 99.52 % degradation at pH 4 with 20-ppm concentration after 60 min under UV irradiation. The degradation followed pseudo-first-order kinetics, with rate constants (k1) ranging from 0.011 to 0.030 min−1, and a minimum half-life of 25.8 min at 15 ppm. Hydroxyl radicals (•OH) were identified as the primary reactive species driving the photocatalytic process. The material exhibited excellent reusability, retaining high degradation efficiency over four cycles. Compared to similar photocatalysts, CTAG@NiMg BNC demonstrated superior performance, faster degradation rates, and greater stability. Its enhanced surface area and porosity, as confirmed by BET analysis, contributed to better dye adsorption and faster reaction times. These properties make the CTAG@NiMg BNC a highly efficient, sustainable, and recyclable photocatalyst for environmental remediation, particularly in treating organic pollutants like methyl orange from aqueous solutions.

Multifunctional molecular precursor with tunable nano-microarchitecture enables exceptional electromagnetic waves absorption

Multi-component carbon is a promising candidate for electromagnetic wave (EMW) absorption materials. However, complex and non-green preparation process with low atomic utilization efficiency compromises the merits of carbon materials. Additionally, enhancing the electromagnetic wave absorption (EMWA) is highly desirable. To face the challenge, a multifunctional molecular precursor (DQSDCI) has been developed, characterized by high atom utilization efficiency (high char yield), abundant in-situ nitrogen doping, multi-sites for composite of nano-materials (e.g. CNT) or metal ion (e.g. iron) and green preparation (water solubility). The multi-component carbons derived from DQSDCI, featuring adjustable nanostructures (nanoribbons or nanosheets) and modifiable porosity, demonstrate outstanding EMWA. The multicomponent carbon of DQSDCI, iron and CNT (DQSDCI-Fe-CNT-700) demonstrated a minimum reflection loss (RLmin) of −69.57 dB and a maximum effective absorption bandwidth (EABmax) of 5.7 GHz at about 2 mm thickness, covering a wide frequency range (4–18 GHz) by controlling the thickness between 1 and 5 mm. Moreover, simulation results indicated that the derived nanosheet is very promising application for aircraft stealth in a monostatic radar system. Abundant in-situ N doping, uniform distribution of MWCNT and ferromagnetic nanoparticles, hierarchical pore structures and various heterogeneous interfaces can synergistically improve the EMW attenuation ability by forming optimal impedance matching and multi-polarization loss.

Enhanced surface emission of bismuth-ion doped glass by adding metal nanoparticles

Enhancing the luminescent properties of doped silica glass has garnered significant interest due to its potential applications in photonics and optoelectronics. In this study, we enhance the surface emission of bismuth(Bi)-doped silica glass by incorporating metal nanoparticles. Utilizing finite-difference time-domain (FDTD) simulations, we observed a significant increase in surface emission following population inversion. We developed a novel algorithm to achieve a uniform distribution of nanoparticles in a two-dimensional computational model, ensuring that the distribution is physically accurate. Through systematic investigation, we explored the effects of the number, distribution, and size of silver nanoparticles on the surface emission enhancement of Bi-doped glass. Our results demonstrate that under optimal conditions, the surface emission enhancement can reach nearly 72%. Additionally, we evaluated the impact of various metal nanoparticles, finding that gold, silver, copper, and platinum positively influence surface emission enhancement, while titanium has an inhibitory effect. This study underscores the potential of metal nanoparticles to significantly improve the luminescent properties of doped glass, paving the way for advanced applications in photonic devices.

Preparation of salt-free Pleurotus eryngii protein with enhanced colloidal stability and emulsifying properties by ceramic membrane filtration

Fungi proteins represent a potential alternative to animal proteins, which are regarded as a prospective source of edible proteins due to more sustainable and efficient cultivation of fungi. Nevertheless, the extraction of fungi proteins typically involves alkali extraction combined with acid precipitation (AEAP), yielding considerable amounts of salt that causes aggregation and inferior functional properties of proteins. In this study, we put forward a novel extraction method by direct filtration of Na+ and OH− from the alkaline extraction solutions using ceramic membranes. This method enabled the continuous, efficient and cost-effective production of Pleurotus eryngii protein (PEP). The PEP prepared by this technology featured a uniform distribution of nanoparticles (∼129.5 nm) with higher water dispersity, colloidal stability and surface active properties as compared to that prepared by the AEAP method. Moreover, the microstructures of PEP can be tailored with various nanoparticle sizes and size distribution profiles, allowing for the adjustment of long-term stabilities and surface activities. Our study renovated the production technology of fungi proteins to enhance their functionalities as well as the application prospects in the future food industry.

Coordination Regulation Strategy in Fabricating Bi2S3@CNFs Composites with Uniform Dispersion for Robust Sodium Storage.

To solve large volume change and low conductivity of Bi2S3-based anodes, a coordination regulation strategy is proposed to prepare Bi2S3 nanoparticles dispersed in carbon fiber (Bi2S3@CNF) composites. It has been discovered that introducing trimesic acid as a ligand can significantly improve the loading and dispersion of Bi3+ in polyacrylonitrile fibers. The results exhibit that Bi2S3 nanoparticles of 200-300 nm are uniformly anchored on the superficial surface layer of CNFs, and Bi2S3 nanoparticles of about 20 nm are evenly dispersed in the interior of CNFs. Assessed as sodium-ion batteries' anode material, the discharge capacity of the Bi2S3@CNF anode in the second cycle is 669.3 mAh g-1 at 0.1 A g-1 and still retains 620.2 mAh g-1 after 100 cycles, with the capacity retention rate of 92.7%. Even at 0.5 A g-1, the specific capacity of the second cycle is 432.99 mAh g-1, which still keeps 400.9 mAh g-1 after 800 cycles, with a retention rate of 92.5%. The excellent cycle stability is mainly attributed to the uniform distribution of small Bi2S3 nanoparticles in CNFs providing abundant active sites, preventing side reactions, relieving volume expansion, improving the electrical conductivity, and accelerating the electrochemical reaction kinetics.

Effects of Pt doping on surface properties and quenching of band edge emission in ZnO

Pt doped ZnO thin films were synthesized on soda-lime glass substrates using a cost-effective sol-gel method, followed by spin coating and thermal annealing at various temperatures. Several characterization techniques such as UV–Vis absorption spectroscopy, photoluminescence (PL), field emission scanning electron microscopy (FESEM), time-of-flight secondary ion mass spectroscopy (ToF-SIMS), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS) are exploited to investigate the Pt doping effects on surface and optical properties of ZnO thin films. UV–Vis analysis demonstrated a slight decrease in the optical band gap from 3.3 eV to 3.2 eV with increased annealing, indicating enhanced suitability for optoelectronic applications. FESEM imaging revealed distinct worm-like structures and small Pt metal nanoparticles in unannealed samples, while thermal treatment supported the formation of spherical Pt nanoparticles and improved conductive pathways in the films. The Wagner diagram, coupled with Auger line transitions from XPS, quantified the oxidation states and chemical environments of Zn and Pt, respectively. Notably, the observed changes in the binding energy of the Zn-2p junction and the kinetic energy of the Zn-LMM Auger junction were significantly influenced by the Pt doping and the electronic properties of the substrate. The Wagner diagram provided a comprehensive visual representation of the parameters, facilitating a deeper understanding of electronic interactions and structural dynamics at the atomic level. XPS results confirmed the presence of ZnO, Zn(OH)2, Pt0 and PtO2 phases, indicating stability and constutient's interactions. ToF-SIMS also validated the uniform distribution of Pt nanoparticles within the ZnO thin film, confirming the effectiveness of the sol-gel method. As a result of Pt doping, PL studies revealed a large quenching effect on band edge emission in the UV and visible emission region of ZnO thin film, which is due to Pt acting as a recombination center for photogenerated carriers. Overall, our results highlight the influence of annealing and Pt incorporation on the optical and structural properties of ZnO thin films and highlight their potential applications for photonics and catalysis.

Deciphering the Role of Inorganic Nanoparticles' Surface Functionalization on Biohybrid Microbial Photoelectrodes.

Shedding light on the interaction between inorganic nanoparticles (NPs) and living microorganisms is at the basis of the development of biohybrid technologies with improved performance. Au NPs have been shown to be able to improve the extracellular electron transfer (EET) in intact bacterial cells interfaced with an electrode; however, detailed information on the role of NP-surface properties in their interaction with bacterial membranes is still lacking. Herein, we unveil how the surface functionalization of Au NPs influences their interaction with photosynthetic bacteria, focusing on cell morphology, growth kinetics, NPs localization, and electrocatalytic performance. We show that functionalization of Au NPs with cysteine in the zwitterionic form results in a uniform NPs distribution in purple bacteria, specifically locating the NPs within the outer-membrane/periplasmic space of bacterial cells. These biohybrid cells, when coupled with an electrode, exhibit enhanced EET and increased (photo)current generation, paving the way for the future development of rationally designed biohybrid electrochemical systems.

Direct fabrication of polycrystalline γ-alumina nanochains-supported Pt nanoparticles on macroscopic ceramic substrates

We report the direct fabrication of polycrystalline γ-Al2O3 nanochains-supported Pt nanoparticles on macroscopic substrates, such as monolithic honeycombs and porous disc-typed ceramics, via chemical vapor deposition. We also investigate solid-gas reactions between the γ-Al2O3 nanochains@Pt nanoparticles and CO using in-situ transmission electron microscopy (TEM). The SEM, TEM, STEM, and XRD patterns reveal that γ-Al2O3 nanochains, 80 nm in diameter, were uniformly formed on the surfaces of macroscopic ceramic substrates. High-resolution TEM (HTEM) images confirm the polycrystalline and kinking structures connecting the nanochains. The coating thickness of γ-Al2O3 nanochains layer is approximately 100㎛. The EDX images and XPS graphs indicate that Pt nanoparticles, 3.5 nm in diameter, are well-coated on the surfaces of the γ-Al2O3 nanochains. The uniform distribution of Pt nanoparticles is precisely controlled utilizing autogenic pressure reaction. Additionally, in-situ observation significantly highlights the physicochemical phenomena of the γ-Al2O3 nanochains@Pt nanoparticles over time under CO supply at 300 °C. Coke formation was accelerated on the surface of catalysts as increase of CO partial pressure increase, while Pt nanoparticles is very stable without the migration and aggregation.