Metal Nanoparticles Research Articles

Ferrocene-Functionalized Atomically Precise Metal Clusters Exhibit Synergistically Enhanced Performance for CO2 Electroreduction.

The integration of organometallic compounds with metal nanoparticles can, in principle, generate hybrid nanocatalysts endowed with augmented functionality, presenting substantial promise for catalytic applications. Herein, we synthesize an atomically precise metal cluster (Ag9Cu6) catalyst integrated with alkynylferrocene molecules (Ag9Cu6-Fc). This hybrid catalyst design facilitates a continuous electron transfer channel via an ethynyl bridge and establishes a distinctive local chemical environment, resulting in remarkably enhanced catalytic activity in CO2 electroreduction. The Ag9Cu6-Fc catalyst achieves a record-high product selectivity of CO Faradaic efficiency of 100% and an industrial-level CO partial current density of -680 mA/cm2, surpassing the performance of the Ag9Cu6 cluster (62% and -230 mA/cm2, respectively) without ferrocene functionalization in a membrane electrode assembly cell. Operando experimental and computational findings offer valuable insights into the role of ferrocene functionalization in synergistically improving the catalytic performance of metal clusters, propelling the advancement of metallic-organometallic hybrid nanoparticles for energy conversion technologies.

Time-dependent quantum/continuum modeling of plasmon-enhanced electronic circular dichroism.

In this work, we present a multiscale real-time approach to study the plasmonic effects of a metal nanoparticle (NP) on the electronic circular-dichroism (ECD) spectrum of a chiral molecule interacting with it. The method is based on the time-evolution of the molecule's time-dependent wavefunction, expanded in the eigenstates of a perturbed Hamiltonian. A quantum description of the molecular system is coupled to a classical representation of the NP via a continuum model. The method is applied to methyloxirane and peridinin at various distances (1, 3, and 5nm) with respect to a gold NP surface. While no remarkable effect is observed for methyloxirane at any studied distance, an enhancement appears when the peridinin lies at 1nm and the pulse is linearly polarized perpendicularly to the molecular axis, with the ECD signal centered at 4.1eV increased by a factor of around 20. These results are rationalized looking at the gap between the plasmonic peak of the NP at around 2.5eV and the molecular excitations: the smaller the gap between molecular and plasmonic excitations, the larger the plasmonic enhancement of the ECD signal. Moreover, ECD peaks are selectively enhanced due to the favorable coupling between the pulse polarization and the combined effect of electric and magnetic dipole moments. This approach allows one to go through the electronic structure and dynamics of chiral molecules for obtaining a realistic description of plasmon-mediated ECD spectra, e.g., paving the way to applications to molecules of biological relevance interacting with nanostructures of experimental interest.

Morphology-controlled mesoporous core–shell carbon nanospheres decorated with Cu nanoparticles as highly efficient and reusable catalyst

Environmental pollution caused by industrial waste has recently become a serious issue. Therefore, effective pollutant removal using nanotechnology is required, in which catalysts based on precious metals, such as Pt, Ag, Au, and Pd, are widely utilized. However, the manufacturing costs of precious metal catalysts are high. In this study, copper, a promising metal for catalysis, is evaluated as an alternative to precious metal catalysts because of its low cost, high efficiency, and abundant natural reserves. However, nanoparticle agglomeration is problematic when evaluating the catalytic performance of isolated metal nanoparticles. To solve this problem and maintain a high catalytic activity of Cu, in this study, Cu was loaded on a mesoporous carbon support derived from a carbon precursor with a core–shell structure. The core–shell-structured carbon precursor was obtained by coating resorcinol-formaldehyde polymer spheres as the core with a 50 nm thick polydopamine shell with 10 nm mesopores through π–π stacking interactions. A copper precursor was used to form Cu(OH)2 on the surface of the support, and then the nanocomposite was synthesized at 500 °C for 2 h. The synthesized copper-carbon nanocomposite exhibits high catalytic activity owing to its high specific surface area, porosity, and accessible internal space. It exhibits excellent catalytic activity and stability, along with excellent reusability, in the reduction of 4-nitrophenol to 4-aminophenol using NaBH4. Moreover, excellent catalytic activity, exceeding 99 %, was achieved in the reduction of another organic dye, methylene blue.

Using Support Effects to Increase the Productivity of Immobilized Ruthenium Hydride Catalysts for the Hydrogenation of CO2.

Interfaces between catalytically active metal surfaces/sites and metal oxides (such as those formed by metal oxides covering metal nanoparticles by strong metal-support interactions) allow both the metal and metal oxide to react with substrates simultaneously and are important for the activity of many heterogeneously catalyzed reactions. However, similar interactions for well-defined immobilized catalysts have not been investigated, despite their potential for increasing catalytic activity. We test the reactivity of a ruthenium hydride [H2Ru(PPh3)2(Ph2P)2NC3H6Si(OEt)3 (1)] in the amine-promoted hydrogenation of CO2 as both a homogeneous catalyst and anchored on SiO2, Al2O3, ZnO, and SBA-15. Anchoring 1 on the surfaces resulted in varying degrees of surface collapse (formation of H-Ru-O linkages to the surface), with ZnO and confinement in SBA-15 pores giving the least surface collapse. Immobilization of 1 on ZnO gave a 6-fold improvement of the catalytic rate over the corresponding homogeneous catalyst. This increase in the catalytic productivity was only possible when the complex was in close contact with ZnO and is most likely due to a combination of increased catalytic activity and slower deactivation. These results demonstrate the ability of surface effects to vastly improve the productivity of even mediocre catalysts upon surface immobilization.

Green Synthesis of Noble Metal Nanoparticles: Nonlinear Optics and Applications

This study presents a green method for synthesising gold nanoparticles (AuNPs) and silver nanoparticles (AgNPs) employing Gum Arabic extract as a reducing and stabilising agent. The synthesised nanoparticles are characterised using UV-Vis absorption spectroscopy and transmission electron microscopy (TEM). The visible colour change and the presence of surface plasmon resonance (SPR) peaks confirmed the formation of silver and gold nanoparticles. The size of the nanoparticles was determined from the UV-Vis spectra data, and the results were compared to sizes measured by TEM. The nonlinear refraction (n2) and nonlinear absorption (b) coefficient of AgNPs and AuNPs at 488 and 514 nm were investigated under continuous wave (CW) mode excitation using the Z-scan technique. By fitting the experimental data to the Z-scan theoretical equations, the nonlinear refraction index and the nonlinear absorption coefficient were found. The origin of the nonlinearities was discussed, and it was proposed to be of thermal effect for the nonlinear refractive index and Reverse Saturation Absorption (RSA) for nonlinear absorption. Optical limiting and switching were demonstrated by taking advantage of the samples' nonlinear optical characteristics.

Combustion synthesis and spark plasma sintering processing of (1‐x)Ba(Zr₀.₂Ti₀.₈)O₃‐x(Ba₀.₇Ca₀.₃)TiO₃ ceramics

AbstractSolution combustion synthesis (SCS) has proven to be one of the simplest and fastest methods, using inexpensive materials and resulting in homogeneous stoichiometry with nanometric particle sizes. The spark plasma sintering (SPS) method has been used to obtain high‐density ceramic materials with excellent control of microstructure. This work reports the successful combination of these two techniques for the fabrication of the high‐density lead‐free ferroelectric system (1‐x)Ba(Zr₀.₂Ti₀.₈)O₃‐x(Ba₀.₇Ca₀.₃)TiO₃. The X‐ray diffraction of the powder indicates the majority formation of the perovskite structure and other residual reaction products, indicating a reactive powder. The SPS method resulted in highly densified samples, reaching relative density values close to 99% with a single‐phase perovskite structure. Rietveld refinement revealed the presence of at least two perovskite phases, independent of calcium concentration. Dielectric measurements showed anomalies in both the real and imaginary parts of the dielectric permittivity, which are typical of phase transitions and a low dielectric loss for all compositions. This study shows that the combined use of SCS and SPS technique can be a powerful protocol to produce dense, fine‐grained lead‐free ferroelectric ceramics at relatively low temperatures and in short time periods.

Ultra-small Metallic Nickel Nanoparticles on Dealuminated Zeolite for Active and Durable Catalytic Dehydrogenation.

Each step in the catalyst synthesis process plays an important role in tuning the catalyst structures. For zeolite-supported nickel catalysts, we found the conventional calcination-reduction method typically leads to the formation of large nickel particles, but a pre-aging in hydrogen or nitrogen at a low temperature prior to final reduction can result in ultra-small nickel nanoparticles in a metallic state. This pre-aging treatment facilitates the interaction between Ni2+ cations and silanol nests on zeolite before the decomposition of the metal salt, leading to the formation of nanoparticles with an average diameter of ~1.2 nm. In contrast, the pre-calcination in oxygen caused the Ni2+ aggregation before the decomposition of the metal salt precursor, yielding nickel nanoparticles larger than 5 nm. Given the structure sensitivity of nickel in cyclohexane dehydrogenation for hydrogen production, the ultra-small nickel nanoparticles exhibited significantly enhanced activity and durability compared to previous nickel catalysts.

Ultra‐small Metallic Nickel Nanoparticles on Dealuminated Zeolite for Active and Durable Catalytic Dehydrogenation

Each step in the catalyst synthesis process plays an important role in tuning the catalyst structures. For zeolite‐supported nickel catalysts, we found the conventional calcination‐reduction method typically leads to the formation of large nickel particles, but a pre‐aging in hydrogen or nitrogen at a low temperature prior to final reduction can result in ultra‐small nickel nanoparticles in a metallic state. This pre‐aging treatment facilitates the interaction between Ni2+ cations and silanol nests on zeolite before the decomposition of the metal salt, leading to the formation of nanoparticles with an average diameter of ~1.2 nm. In contrast, the pre‐calcination in oxygen caused the Ni2+ aggregation before the decomposition of the metal salt precursor, yielding nickel nanoparticles larger than 5 nm. Given the structure sensitivity of nickel in cyclohexane dehydrogenation for hydrogen production, the ultra‐small nickel nanoparticles exhibited significantly enhanced activity and durability compared to previous nickel catalysts.

Nano–Bio Interaction and Antibacterial Mechanism of Engineered Metal Nanoparticles: Fundamentals and Current Understanding

Nano–Bio Interaction and Antibacterial Mechanism of Engineered Metal Nanoparticles: Fundamentals and Current Understanding

Potential applications of Bacillus thuringiensis Berliner in agriculture, medicine and environment

Bacillus thuringiensis (Bt) is renowned for its insecticidal activity against a wide range of target pests. Bt formulations offer safe alternatives to chemical insecticides, effectively eliminating insects using toxins and enzymes such as chitinases and metalloproteases. This bacterium has transformed pest management through the development of genetically modified insect-resistant crops, providing targeted protection. Beyond pest control, Bt serves as an alternative to antibiotics, fertilizers, bioremediation agents and for nanomaterial synthesis. While its effectiveness in insect control contributes to sustainable farming practices, Bt further promotes plant growth as a biofertilizer and growth enhancer. Additionally, it plays various roles in medicine and environmental applications. Bacteriocins, proteins produced by Bt, exhibit high efficacy against pathogenic bacteria and demonstrate some fungicidal activity, offering potential applications in medicine and food preservation. Bt’s influence extends to environmental bioremediation, where it targets heavy metals and dyes. It is also involved in the synthesis of metal nanoparticles and exhibits anti-cancer activity by targeting various cancerous cells. Overall, Bt showcases a broad spectrum of activity across agriculture, medicine and environmental sectors, highlighting its potential to enhance crop productivity, improve human health and reduce environmental pollution.

Efficacy Assessment of Sulfated Flavanol Functionalized Silver Nanoparticles against MCF-7 Breast Cancer

Aim: The present research work aims to formulate a cost-effective and less toxic drug for specific and selective delivery at the tumor site. Background: Existing therapeutics, such as chemo, surgery, etc., for fast-paced MCF-7 breast cancer, still face challenges, especially due to their toxic side effects. The unique properties of metal nanoparticles embedded in anti-oxidant plant polymers have sparked great interest in the formulation of less toxic-targeted drugs for cancer cure. Objective: The present work aims to synthesize a targeted formulation of colloidal nanosilver by surface engineering of silver nanoparticles using plant polymers in electrolytic deposition technique, developed indigenously at the institute lab. Methods: A current is passed through an elctrolyte, AgNO3, which splits it into ions. The positive ions of Ag deposit over LDPE wrapped carbon cathode and negative ion, NO3, is liberated. Ag+ ions get capped in-situ. These surface-modified silver nanoparticles formulate a colloidal solution. UV-visible and FTIR spectroscopy, TEM-EDX, and XRD were used to validate asprepared formulation and in vivo human tumor xenograft model in NOD-SCID mouse for efficacy against MCF-7 breast cancer. Results: The as-synthesized formulation consists of pure spherical poly-dispersed silver nanoparticles of average size 5.4 nm, coated with sulphated flavanols. The efficacy evaluation reported that it significantly, T/C = 0.53, reduced tumor volumes with a 100% survival rate and change in animal body weight <4 gms. Conclusion: The as-synthesized formulation can be used as a potential neo-adjuvant or adjuvant drug along with existing therapeutics for MCF-7 breast cancer, significantly reducing the toxicity and cost.

Supramolecular pre‐organisation rhodium and iridium metal complexes within M12L24 self‐assembled nanospheres for the confined synthesis Rh/Ir alloyed nanoparticles

Controlling the size and composition of metal nanoparticles is of considerable interest, as these are essential to their catalytic properties. We report the controlled synthesis Rh nanoparticles by preorganisation of metal complexes inside Pt12L24 nanospheres based on complementary hydrogen bonds before the reduction step that leads to nanoparticle formation. The encapsulated RhI complexes (Rh‐s @ G‐sphere) led to reasonable size control (2.8 ± 0.9 nm). We also report the formation of Rh‐Ir alloyed nanoparticles with varying Rh/Ir compositions. These heterometallic particles were evaluated in the hydrogenation of cinnamaldehyde (7) as a probe reaction. Besides a high activity in this probe reaction, the Rh particles also catalyzed the conversion of the solvent (CH3CN). The formed basic amine leads to follow‐up reactions of the product and compatibility issues with the hosting nanosphere. The solvent hydrogenation was effectively suppressed by using the Rh:Ir alloyed nanoparticles, provided that they contain >66% Ir. The Rh:Ir alloyed nanoparticles displayed high catalytic activity, reaching optimal selectivity and activity at an 8:16 ‐ Rh:Ir ratio. The combined catalytic results illustrate that pre‐organisation of the metal complexes in the nanosphere before the reduction with hydrogen effectively facilitates the formation of Rh:Ir alloyed nanoparticles.

Characterization of Bimetallic Pd-Fe Nanoparticles Synthesized in Escherichia coli.

Biologically mediated nanoparticle (NP) synthesis offers a reliable and sustainable alternative route for metal NP production. Compared with conventional chemical and physical production methods that require hazardous materials and considerable energy expenditure, some microorganisms can reduce metal ions into NPs during standard metabolic processes. However, to be considered a feasible commercial option, the properties and inherent activity of bio-NPs still need to be significantly improved. In this work, we present an Escherichia coli-mediated synthesis method for catalytically active Pd-Fe NPs. The produced biogenic Pd-Fe NPs with varying Fe content were characterized using complementary analytical techniques to assess their size, composition, and structural properties. In addition, their catalytic performance was assessed by using standardized chemical reactions. We demonstrate that the combination of Pd with Fe leads to synergistic effects that enhance the catalytic performance of Pd NPs and make biogenic Pd-Fe NPs excellent potential substitutes for currently used catalysts. Briefly, the apparent rates for the model reaction of 4-nitrophenol reduction to 4-aminophenol catalyzed by Pd-based nanoparticles were as high as 0.1312 min-1 using bimetallic Pd-Fe NPs, which is far superior to the rates of monometallic Pd NPs counterparts. This study provides a feasible strategy for the synthesis of multimetallic Pd-based NPs using common microbial processes. It emphasizes the potential of biogenic Pd-Fe NPs as efficient and sustainable catalysts for hydrogenation reactions, offering an environmentally friendly synthesis for various applications, including wastewater treatment and the production of fine chemicals.

Efficacy of copper and silver nanoparticles on seedling growth, biochemical and antioxidant potential of Capsicum annuum L., in vitro and ex vitro

Metallic nanoparticles (MNPs) were synthesized using the chemical reduction method and evaluated in vitro and ex vitro on Capsicum annuum. The impact of MNPs, namely Ag, Cu, CuAg NPs, Silver nitrate (AgNO3), and Copper sulfate pentahydrate (CuSO4·5H2O) as bulk salts, on the physiological, biochemical, and antioxidative profiles of seedlings in C. annuum were examined in this work. Both NPs Primed (NPsP) and NPs Supplemented (NPsS) seeds showed 80–90 % and 90–100 % germination, respectively, after 15 days of inoculation on Murashige and Skoog medium (MS) medium, compared to the control (75 %) and 93–97 % in vitro. The seedling length, weight, and vigour index improved significantly in response to in vitro and ex-vitro NP administration. After 45 days of nanoparticle (NPs) treatment, the levels of chlorophyll and carotenoids in NPsP seedlings increased by 65–244 % and 41–203 % in ex vitro, respectively, compared to NPsS seedlings, which showed an increase of 4–114 % and 26–107 %, respectively. Additionally, the total phenolic content (TPC) and total flavonoid content (TFC) were significantly enhanced in NPsP seedlings, showing an increase of 79–173 % and 62–168 % in ex vitro, compared with NPsS seedlings, which showed an increase of 3–73 % and 22–98 %, respectively. MNPs increased the total protein content in NPsP seedlings by 26–106 % in ex vitro (5–113 %), compared to NPsS seedlings. In the NPsP seedlings, superoxide dismutase (SOD), peroxidase (POD), and proline content rose by 15–47 %, 38–83 %, and 65–121 % at ex vitro (10–61 %), (6–68 %), and proline content decreased, respectively, as compared to NPsS treated seedlings. Malondialdehyde (MDA) level in NPsP seedlings decreased (4–33 %) in ex vitro compared to NPsS seedlings, indicating ROS scavenging and healthy seedling development. In the current study, increased seed germination aided rapid seedling development. Thus, nanoparticles promote seed germination in C. annuum by overcoming the unfavourable effects of reactive oxygen species (ROS) and improving the antioxidative defence system, resulting in increased seedling development.

Dynamics of metal/metalloid bioaccumulation and sensitivity in post-larvae shrimp (Macrobrachium rosenbergii) exposed to settleable atmospheric particulate matter from an industrial source

The metallurgy industry is a potent global source of particulate matter (PM) atmospheric emissions. A portion of this PM may settle in aquatic (SePM) carrying metal/metalloid particles and metallic nanoparticles. Surprisingly, this form of contamination has not received due attention from most environmental monitoring agencies. We analyzed the effect of exposure to SePM on shrimp post-larvae, a critical stage for the viability of shrimp populations and for the trophic chain. After acclimation, shrimp were exposed to contaminants using a randomized experimental design—a 4 × 4 factorial arrangement with 2 factors: exposure time (24, 48, 72, and 96 h) and SePM concentration (0.00, 0.01, 0.10, and 1.00 g L−1). The bioaccumulation of metals, contamination rates, mortality, and ROS-related biomarkers (lipid peroxidation – LPO; DNA strand breakage DNA SB and metallothionein content – MTs;) were evaluated. After contamination, the water contained 27 different metals/metalloids. Post-larvae accumulated metals, such as Cd, Pb, Al, As, Se, Sr, Zr, Ba, La, Ce, W, and Hg. However, the rise in SePM did not result in a proportional bioaccumulation rise, indicating that effective biological barriers may work for some metals. Although the different levels of SePM changed mortality dynamics, they resulted in a similar final lethality (60–80 %). SePM caused significant damage to lipids (increased LPO), genetic material (DNA SB), and increased Mts. Such effects may reflect a particularly deleterious ecological problem as it is present at such an early stage of life. These results identified a clear environmental risk since the lower level of exposure used was 102 times lower than that measured in the habitats affected by local industry. Consequently, our results emphasize the need for clear protocols for monitoring the effects of SePM in aquatic environments.

Role of Nano Catalysts In Green Chemistry

Abstract This study explores the role of nano catalysts in enhancing catalytic performance through their unique properties and applications in sustainable chemistry. Nano catalysts, defined as materials operating at the nanometer scale, typically between 1 and 100 nanometers, exhibit significantly increased surface area and altered electronic properties, leading to improved reaction rates and efficiencies. The investigation highlights the critical properties of nano catalysts, such as their high surface area-to-volume ratio, controlled shapes, and tunable surface functionalities, which contribute to their effectiveness in various catalytic processes. Different types of nano catalysts, including metal nanoparticles, metal oxides, and carbon-based nano materials, are examined for their distinct advantages and applications. Metal nanoparticles, like gold and platinum, offer enhanced catalytic activity due to their unique electronic behaviors, while metal oxides, such as titanium dioxide, provide stability in photocatalytic applications. Additionally, carbon-based nano materials, including carbon nanotubes and graphene, are recognized for their exceptional electrical conductivity and surface area, making them suitable for energy conversion and environmental remediation.

Interfacial effects of gold on PEDOT nanotubes modified electrodes employed for the adsorption of micropollutants

In this work poly(3,4-ethylenedioxythiophene) nanotubes (PEDOT-NTs) containing gold nanoparticles (AuNPs) were electrochemically synthesized and characterized in detail by using in situ Raman spectroelectrochemistry. Combining conducting polymers and metallic nanoparticles (AuNPs) enhanced conductivity and superficial area of PEDOT-NTs, key factors for electrochemical sensors. In order, to better understand the modified electrodes behavior, two different micropollutants, butylparaben and triclosan, were added onto the electrode surface and the spectroelectrochemical characterization was done. The Raman imaging showed that micropollutants adsorption increases the presence of partially oxidized segments in PEDOT nanotubes, showing that PEDOT-NTs/AuNPs modified electrodes has sensitivity to micropollutants presence. In this regard the electrochemical impedance spectroscopy characterization was performed and agrees with the spectroelectrochemical characterization results, in which the charge-transfer resistance increase proportionally with the micropollutants concentration. Therefore, the present work shows the potentiality of combining the unique characteristics of the PEDOT nanotubes decorated with AuNPs nanoparticles to develop devices for detection of organic molecules of environmental interest.

An Overview of Metallic Nanoparticles: Classification, Synthesis, Applications, and their Patents.

Nanotechnology has gained enormous attention in pharmaceutical research. Nanotechnology is used in the development of nanoparticles with sizes ranging from 1-100 nm, with several extraordinary features. Metallic nanoparticles (MNPs) are used in various areas, such as molecular biology, biosensors, bio imaging, biomedical devices, diagnosis, pharmaceuticals, etc., for their specific applications. For this study, we have performed a systematic search and screening of the literature and identified the articles and patents focusing on various physical, chemical, and biological methods for the synthesis of metal nanoparticles and their pharmaceutical applications. A total of 174 references have been included in this present review, of which 23 references for recent patents were included. Then, 29 papers were shortlisted to describe the advantages, disadvantages, and physical and chemical methods for their synthesis, and 28 articles were selected to provide the data for biological methods for the formulation of metal NPs from bacteria, algae, fungi, and plants with their extensive synthetic procedures. Moreover, 27 articles outlined various clinical applications of metal NPs due to their antimicrobial and anticancer activities and their use in drug delivery. Several reviews are available on the synthesis of metal nanoparticles and their pharmaceutical applications. However, this review provides updated research data along with the various methods employed for their development. It also summarizes their various advantages and clinical applications (anticancer, antimicrobial drug delivery, and many others) for various phytoconstituents. The overview of earlier patents by several scientists in the arena of metallic nanoparticle preparation and formulation is also presented. This review will be helpful in increasing the current knowledge and will also inspire to innovation of nanoparticles for the precise and targeted delivery of phytoconstituents for the treatment of several diseases.

Nano - Based Therapeutic Strategies in Management of Rheumatoid Arthritis.

Rheumatoid arthritis (RA) is a chronic autoimmune disease, progressively distinctive via cartilage destruction, auto-antibody production, severe joint pain, and synovial inflammation. Nanotechnology represents as one of the utmost promising scientific technologies of the 21st century. It exhibits remarkable potential in the field of medicine, including imaging techniques and diagnostic tools, drug delivery systems and providing advances in treatment of several diseases with nanosized structures (less than 100 nm). Conventional drugs as a cornerstone of RA management including disease-modifying antirheumatic drugs (DMARDS), Glucocorticosteroids, etc are under clinical practice. Nevertheless, their low solubility profile, poor pharmacokinetics behaviour, and non-targeted distribution not only hamper their effectiveness, but also give rise to severe adverse effects which leads to the need for the emergence of nanoscale drug delivery systems. Several types of nano-diagnostic agents and nanocarriers have been identified; including polymeric nanoparticles (NPs), liposomes, nanogels, metallic NPs, nanofibres, carbon nanotubes, nano fullerene etc. Various patents and clinical trial data have been reported in relevance to RA treatment. Nanocarriers, unlike standard medications, encapsulate molecules with high drug loading efficacy and avoid drug leakage and burst release before reaching the inflamed sites. Because of its enhanced targeting specificity with the ability to solubilise hydrophobic drugs, it acts as an enhanced drug delivery system. This study explores nanoparticles potential role in RA as a carrier for site-specific delivery and its promising strategies to overcome the drawbacks. Hence, it concludes that nanomedicine is advantageous compared with conventional therapy to enhanced futuristic approach.

Bucket effect of Cobalt Nanoparticles and Single Atoms in Nitroarenes Transfer Hydrogenation

Synergetic metal nanoparticles (NPs) and single atoms hold significant potential in reactions that require activating multiple substrate molecules. However, due to the differences in adsorption, activation and kinetics among distinct substrates during the multistep reaction process, the synergy and matching relationship between metal NPs and single atoms remain unclear. In this work, we synthesized a series of Co1-NP/CNT@CN-X dual-site catalysts with tunable molar ratios (X%) of Co single atoms to total Co species through a coordination site regulation (CSR) strategy and investigated the bucket effect of the dual active sites in the transfer hydrogenation of nitro compounds. Density functional theory calculations reveal that active hydrogen generation from ammonia borane hydrolysis primarily occurs at the surface of Co NPs, while nitroarenes hydrogenation predominantly takes place at Co single atoms, which is consistent with experimental findings. The optimized Co1-NP/CNT@CN-7.6 maintains high selectivity for nitro hydrogenation (> 99.9%) and exhibits conversion (99.9%) nearly 3.7 times that of the original Co1-NP/CNT@CN-1.6 catalyst (27%), achieved by overcoming the bucket effect between Co NPs and single atoms. This work not only elucidates the synergistic mechanisms of dual sites in transfer hydrogenation, but also establishes that optimizing matching effect is an effective approach to significantly enhance their catalytic performance.