Ag2O Nanoparticles Research Articles

Green synthesis of AgO nanoparticles using Prosopis Cineraria bark extract and its antibacterial activity

Abstract The green synthesis of AgO nanoparticles (NP) uses plant elements like terpenoids, polyphenols, carbohydrates, enzymes, flavonoids, lipids, and alkaloids as reducing agents. A biodegradable technique produces silver oxide nanoparticles from Prosopis cineraria bark extract. This paper defines a biologically friendly, simple, cost-free, and predictable production of AgO nanoparticles (NP) from Prosopis cineraria aqueous bark extract, as well as their antibacterial efficacy. Silver oxide nanoparticles (NP) were green-produced with a bark extract of Prosopis cineraria, acting as a cap and reducing agent. The XRD study revealed that the AgO NP was in a face-centered crystal structure with a mean crystal size of 69.95 nm. The colour variations were used to detect the silver oxide nanoparticle forms in the extracts, and the successful manufacture of the AgO NP was validated using ultraviolet-visible spectrophotometry, which captured the SPR peak at approximately 601 nm. AgO NP was studied using an SEM to analyse the nanoparticles’ square shape and size. The antibacterial activities of the green synthesis of AgO NP were verified against gram-positive microorganisms like S. aureus, E. faecalis, and S. pneumoniae, and gram-negative microorganisms like E. coli, P. mirabilis, and P. aeruginosa, and the inhibition zones were found. Finally, the AgO NP produced by Prosopis cineraria bark extract is a valuable source of bioactive natural compounds. AgO NP demonstrated our antibacterial properties, which can be employed in future studies using a variety of biological approaches.

Study of a gel dosimeter based on Ag nanoparticles for applications in radiation therapy with synchrotron X-rays at ultrahigh dose rate compared to 60Co γ-rays

A silver nitrate (AgNO3) gel was developed and evaluated as a dosimeter for synchrotron X-ray-based studies in microbeam radiation therapy (MRT) and FLASH radiation therapy. The gel was irradiated at the European Synchrotron Radiation Facility (ID17 Biomedical beamline) with a continuous X-ray spectrum in the 50-600 keV range and a dose rate of 11.6kGy/s. The spectrophotometric response after irradiation at this beamline was compared with the response at a conventional 60Co γ-ray source providing a dose rate of 0.27 Gy/s. Ag+ ions in the gel dosimeter undergo reduction to Ago nanoparticles, as detected at 450 nm, which is a surface plasmon resonance band. The intensity of this band increased linearly with increasing absorbed dose up to 100 Gy, and improved with the addition of glycerol. The gel dosimeter exhibited the lowest detectable dose (LDD) of 75.9% lower and a dose deposition of 76% higher for ID17 beamline irradiation than for 60Co irradiation. The theoretical relative response HQ,Qo for the gel irradiated at the synchrotron was 1.70, which is in close agreement with the experimental relative response FQ,Qo = 1.76. These results confirm the dose enhancement in the gel irradiated with orthovoltage X-rays. The good properties of the silver nitrate gel, together with its increased sensitivity to orthovoltage X-ray irradiation and modest overall uncertainty of 5.8% (2σ), confirm that the gel is a valid dosimeter for measurements at ultrahigh dose rates for synchrotron radiotherapy. The dosimeter is also a promising candidate for dose enhancement factor measurements in nanoparticle-based radiotherapy techniques.

In-situ biosynthesis of metallic nanoparticles using Allium sativum and Chondrilla juncea extract: characterization and application in dye decolorization

The synthesis of catalysts has gained specific concern due to their versatile applications in particular azo dye decolorization. In the current work, metallic nanoparticles (copper and silver) were In-situ biosynthesised using Allium sativum and Chondrilla juncea extract. The obtained Allium-copper oxide and Allium-silver oxide materials were analyzed using SEM, TEM, FT-IR, TGA-DTG, SEM, TEM, and XRD techniques. Allium peels had a rough surface, with nanoparticles equally distributed over it. The crystal structure of Allium peels was altered after the addition of CuO and AgO nanoparticles. The highest residual mass values in the prepared materials indicated that the metallic nanoparticles were, in situ, formed. The prepared materials had worse thermal stability than Allium peel powders. The azo dyes, Calmagite and Naphthol Blue Black B were tested in the catalytic power of the resulting materials. The decolorization process was affected by the dye structure, amount of H2O2, dye concentration, time of reaction, and temperature of the bath. The activation energy values for Allium-CuO were 18.44 kJ mol−1 for calmagite, and 23.28 kJ mol−1 for naphthol blue black, respectively. Nevertheless, the energy values for Allium-AgO were 50.01 kJ mol−1 for calmagite and 12.44 kJ mol−1 for Naphthol blue black. The calculated low energy values for the prepared materials suggested the high efficiency of the use of these catalysts in azo dye decolorization under the change of some main experimental conditions.

The Synthesis and Application of Chitosan@Ag2O@Mn3O4 Three‐Phase Nanocomposite as a Heterogeneous Catalyst in the Synthesis of 2‐Hydroxynaphthalenepyrimidine Trione

ABSTRACTThe catalyst is often the most expensive element in a chemical process, rather than the reactants or products. Apart from the financial benefits, it is equally crucial to recover and reuse the catalyst to prevent waste and enhance the process's greenness. This study successfully synthesized the new, superior, and recyclable heterogeneous chitosan@Ag2O@Mn3O4 three‐phase nanocatalyst with high surface area and stability using Ag2O and Mn3O4 nanoparticles that stabilized on chitosan by copreparation method and was characterized by Fourier transform infrared (FT‐IR), scanning electron microscopy (SEM), energy dispersive X‐ray (EDX), transmission electron microscopy (TEM), surface mapping (mapping), X‐ray diffraction (XRD), Brunner–Emmett–Teller (BET), thermal gravimetric analysis (TGA), and differential scanning calorimetry (DSC) techniques in detail. Following, the efficiency of the synthesized nanocatalyst in the preparation of 2‐hydroxynaphthalenepyrimidine triones using the reaction of aromatic aldehydes, β‐naphthol, and barbituric acid derivatives was investigated and proved. The advantages of this method include performing reactions at room temperature, green media, short reaction times, and the easy purification of the products.

Development of Tetracycline by AgO Nanoparticles and Studying its Activity on Antibiotic-Resistant Bacteria

General background: Antibiotic resistance in bacteria has become a critical global health issue, necessitating the development of new strategies to enhance antibiotic efficacy. Specific background: Nanoparticles, particularly silver nanoparticles (AgNPs), have emerged as potential enhancers of antibiotics due to their unique properties and interactions with bacterial cells. Knowledge gap: However, the combination of nanoparticles with existing antibiotics, such as tetracycline, and their impact on bacterial inhibition and safety has not been fully explored. Aims: This study aims to investigate the antibacterial activity of silver oxide nanoparticles (AgO NPs) combined with tetracycline (TCS) and evaluate their effectiveness against resistant bacterial strains. Results: AgO NPs were synthesized using a photodeposition method, yielding nanoparticles with an average diameter of 2.24 nm. The AgO NPs + TCS combination demonstrated superior antibacterial activity, with a minimum inhibitory concentration (MIC) of 16 μg/mL against Staphylococci and 32 μg/mL against Pseudomonas aeruginosa, significantly outperforming standard tetracycline. Hemolysis assays confirmed the safety of the synthesized compound at all concentrations. Novelty: Silver oxide nanoparticles and tetracycline exhibit a unique synergistic interaction, enhancing antimicrobial effects by increasing bacterial membrane permeability, facilitating greater antibiotic infiltration. Implications: These findings suggest that AgO NPs combined with tetracycline offer a promising solution to overcome bacterial resistance, providing a potent and safe alternative to conventional antibiotic treatments. Highlights: AgO NPs and tetracycline show enhanced antibacterial effects. More effective than standard tetracycline against resistant bacteria. Safe with no toxicity observed in hemolysis tests. Keywords: Antibiotic resistance, silver nanoparticles, tetracycline, photodeposition, antibacterial activity

Effect of Ag2O nanoparticles on the excited state dipole moment of a novel BMNFC molecules through solvatochromic shift method

We experimentally determined the ground and excited state dipole moments of BMNFC (5-bromo-N’-[(Z)-(4-methoxyphenyl)methylidene]naptho[2,1-b]furan-2-carbohydrazide) dye using the solvatochromic shift method and various solvatochromic correlations, including Lippert’s, Bakhshiev’s, Kawski-Chamma-Viallet’s, and solvent polarity equations. We employed the B3LYP/6-311G (d) level of theory to calculate the HOMO, LUMO, and MESP. In this study, we synthesized Ag2O nanoparticles using a quick and cost-effective chemical reduction method. Then, we used carboxymethylcellulose (CMC) as a capping agent. We studied the size, shape, and composition of these nanoparticles using a variety of analytical techniques. Transmission electron microscopy (TEM) analysis revealed a spherical morphology with an average diameter of 17 nm. The results show that adding Ag2O nanoparticles to BMNFC molecules changes their symmetric charge distribution, which in turn enhances their dipole moment. Molecules of enhanced dipole moment have attractive features in biomedical applications. Each molecule’s symmetry point group determines the extent to which nanoparticles affect the BMNFC molecule.

Optimizing Titanium Carbide-Silver Oxide Nanostructures for Targeted Cancer Therapy: Synthesis, Functionalization, and In Vitro Evaluations.

Introduction Cancer remains a significant health challenge, and nanoparticles (NPs) are promising candidates for cancer treatment due to their unique physicochemical properties and ability to selectively target tumour cells. Two-dimensional (2D) nanomaterials, such as MXenes, have attracted interest due to their electronic structures, optical properties, catalytic abilities, and exceptional physicochemical attributes. MXenes are highly suitable for surface functionalization or modification, and their unique properties make them promising candidates for various applications in the biological field. Silver-based compounds have shown remarkable potential in biomedical fields, with silver oxide (Ag₂O) NPs finding applications in various domains. The fabrication of titanium carbide (Ti₃C₂)-Ag₂O heterostructures has been investigated for their anti-cancer properties by conducting cell viability assays on different cell lines. Aim To synthesize and characterize Ti₃C₂-Ag₂O, and to assess its in vitro anti-cancer activity. Materials and methods Ti₃C₂ synthesis begins by dissolving Ti₃AlC₂ powder in a 50% v/v hydrofluoric (HF) acid solution, allowing the aluminium to be etched away. This process should be conducted with continuous stirring for 24 to 48 hours at ambient temperature. Following this, filter the resulting suspension to eliminate aluminium particles and HF, and subsequently wash the Ti₃C₂ MXene with distilled water until a neutral pH is attained. The MXene should then be dispersed in ethanol, and sonication in deionized (DI) water or an alternative solvent should be employed to achieve exfoliation into monolayer or few-layer MXenes. To prepare Ag₂O NPs, dissolve silver nitrate (AgNO₃) in DI water to create a 0.1 M solution, and concurrently prepare a separate 0.1 M sodium hydroxide (NaOH) solution. Introduce the NaOH solution to the AgNO₃ while stirring until a precipitate is observed. The mixture should then be filtered, washed with distilled water, and the NPs dried at 60°C for 12 hours. To fabricate the MXene-Ag₂O composite, disperse the MXene nanoflakes in a solvent through sonication, incorporate the Ag₂O NPs, and stir the mixture for 24 hours. Finally, centrifuge the resultant mixture to isolate the composite, wash it with solvent, and dry it under vacuum conditions. Results The presence of Ag₂O particles on Ti₃C₂ nanosheets was observed, and the high crystallinity of the compound was confirmed through X-ray diffraction (XRD), energy-dispersive spectroscopy (EDS), and scanning electron microscopy (SEM) analyses. These tests verified that the compound was free of impurities and exhibited anti-cancer properties. Conclusion The synthesis of Ti₃C₂ MXenes and Ag₂O NPs was achieved and confirmed through structural characterization methods, including SEM, XRD, and EDS. SEM provided detailed insights into the morphology and distribution of the nanostructures, while XRD and EDS verified their phase purity and elemental composition. Functionalization strategies were employed to enhance the stability and bioactivity of the nanocomposites. In vitro evaluations demonstrated promising anti-cancer activity, indicating that the Ti₃C₂-Ag₂O composites effectively target and inhibit cancer cell growth.

Probing variation of the structure and electrical conductivity of functionalized PVA based composite films doped with silver nanoparticles and irradiated by gamma rays

Polyvinyl alcohol/sulfuric acid/ethanol films doped with nano-silver particles are prepared using in-situ chemical reduction method. The as-prepared films are irradiated with gamma rays at dose range 0–50 kGy. The elemental analysis of as-prepared samples using energy dispersive x-ray spectroscopy (EDXS) showed presence of oxygen and silver peaks which refers to the probable formation of silver oxide nano-particle (Ag2O NPs) phase. Moreover, scanning electron microscope (SEM) analysis confirmed that the inserted Ag nanoparticles have regular and uniformly distributed pores within the PVA network. X-ray diffraction (XRD) measurements indicated that of Ag2O and Ag nanoparticles are embedded in the PVA matrix in cubic face-centered structure. Structural variations due to gamma irradiation are also probed by high-resolution transmission electron microscopy (HR-TEM) which displayed that the diameter of encapsulated Ag nanoparticles increases from ∼15 nm up to 34 nm against irradiation dose. The measured dc electrical conductivity results indicated that the thermal activation energy decreased from 0.95 eV to 0.56 eV as a sequence of irradiation dose in the range 0–50 kGy The evaluation of the frequency exponent factor, s, derived from the measured ac conductivity data indicated that correlated barrier hopping (CBH) is the most probable conduction mechanism for the present films. The measured dielectric constants and Cole-Cole diagrams are employed in the analysis of the dependence of the dielectric constant on the irradiation dose.

Synergistic photocatalytic and antibacterial efficacies of Ag/rGO and Ag/Ag2O/rGO nanocomposites: The impact of oxide formation and ternary heterojunction

This study explores the efficient solvothermal integration of Ag/rGO and Ag/Ag2O/rGO nanocomposites using various solvents and employs thorough characterization procedures. The primary focus is on understanding the nuanced effects resulting from the combination of Ag nanoparticles with rGO nanosheets, particularly in the context of Ag2O formation. For a quantitative assessment of their photocatalytic and antibacterial properties, graphene oxide and silver nitrate (AgNO3) were introduced to create Ag/rGO and Ag/Ag2O/rGO nanocomposites. The results demonstrate a significant enhancement in photocatalytic performance for the Ag/Ag2O/rGO nanocomposite, achieving a rapid degradation of 99.99 % of methylene blue dye within 30 minutes under simulated solar light irradiation. This heightened efficiency is attributed to improved separation and transfer efficiency, as well as the substantial generation of photoinduced carriers due to the incorporation of visibly active Ag2O nanoparticles. Moreover, the Ag/Ag2O/rGO nanocomposite exhibits an enhanced antibacterial activity, reflected in Minimum Inhibitory Concentration (MIC) values of 50 μg/ml for Bacillus cereus and 300 μg/ml for Escherichia coli. The nanocomposite's higher antimicrobial activity against Gram-positive bacteria, particularly Bacillus cereus, is underscored, revealing its potential as an effective antibacterial agent. The formation of a ternary heterojunction in the Ag/Ag2O/rGO nanocomposite results in a notable increase in the production of free radicals, enhancing charge carrier migration and separation efficiency. This quantitative evidence emphasizes the versatile nature of the nanocomposite, highlighting its potential across diverse fields through augmented antibacterial and photocatalytic properties.

Visible-NIR responsive Ag2O couple with MIL-53(Fe) on CS as S-scheme photocatalyst for efficient simultaneous removal of Cr(VI) and norfloxacin

This study addresses the urgent need to develop easily recoverable and efficient photocatalysts for the treatment of compound polluted wastewater. Herein, S-scheme MIL-53(Fe)/Ag2O heterojunctions on a charcoal sponge (CS) were constructed by solvothermal-chemical precipitation method, exhibiting high separation efficiency of photoinduced carriers and reduction–oxidation (REDOX) capacity. The synthesized CS/MIL-53(Fe)/Ag2O was characterized by SEM, TEM, XRD, and XPS, confirming the successful deposition and uniform distribution of MIL-53(Fe) and Ag2O nanoparticles on CS. Moreover, CS/MIL-53(Fe)/Ag2O exhibits an extensive light absorption range from visible to near-infrared (NIR) light, thereby significantly enhancing its photocatalytic activity. In present of H2O2, CS/MIL-53(Fe)/Ag2O demonstrated outstanding removal efficacy of norfloxacin (NFX, 96 %, pH=7) or Cr(VI) (100 %, pH=3) through the photocatalytic-Fenton reaction, which was notably superior to that of CS/MIL-53(Fe) (50.4 % NFX, 56.8 % Cr(VI)) and CS/Ag2O (44.3 % NFX, 38 % Cr(VI)). Importantly, when CS/MIL-53(Fe)/Ag2O was used to treat combined polluted wastewater containing both Cr(VI) and NFX, the removal efficiency of Cr(VI) and NFX showed a significant synergistic effect. Additionally, inhibition zone tests demonstrated that the toxicity of NFX intermediates to E. coli gradually decreased as the degradation of NFX progressed. Furthermore, density functional theory (DFT) calculation and relevant characterization were conducted to elucidate the reaction mechanism of S-scheme heterojunctions, highlighting the enhanced separation rate of photo-induced carriers and REDOX capability. This work not only offers a promising approach for construction of MOF-based S-scheme semiconductor heterojunctions, but also presents promising prospects for the purification of compound polluted wastewater containing norfloxacin and Cr(VI).

Construction of Ag2O/WO3-based hollow microsphere p-n heterojunction for continuous detection of ppb-level H2S gas sensor

Three-dimensional (3D) hierarchical hollow microsphere WO3 and Ag2O/WO3 heterojunction materials were prepared by a simple hydrothermal method for a highly sensitive continuous response H2S gas sensor. The results show that compared with the original WO3 (Ra/Rg=12.5, 10 ppm, 70℃), the sensor based on Ag2O/WO3 has excellent H2S sensing performance at 60℃. Including ultra-high sensitivity (Ra/Rg=207.12, 10 ppm), continuous detection of different concentrations of H2S gas (0.05–50 ppm), fast response capability (15 s), low detection limit (50 ppb), high selectivity and reliable stability. The study of gas sensing mechanism shows that the synthesized 3D hierarchical hollow microsphere structure provides more channels for gas diffusion and transmission. The dispersion of Ag2O nanoparticles (NPs) on the surface of WO3 provides more reactive sites for gas adsorption. At the same time, the charge transfer is promoted by constructing Ag2O/WO3 p-n heterojunction. Sulfurization of Ag2O improved the response value and selectivity to H2S gas. These factors together determine the superior performance of the prepared Ag2O/WO3 H2S-based sensor.

Syzgium cumini seed/poly vinyl alcohol based water resistant biodegradable nano-cellulose composite reinforced with zinc oxide and silver oxide nanoparticles for improved mechanical properties

The current work explored a comparative study of biodegradable jamun seed/polyvinyl alcohol (JS) nanocomposites reinforced with varying concentrations of ZnO and Ag2O nano-fillers. The effect of spherical shaped ZnO and Ag2O nanoparticles (NPs) on the on structure, morphology, swelling and solubility, crystallinity and mechanical properties together with biodegradation performance of the composite films was fully studied. SEM results showed uniform distribution of ZnO and Ag2O nanofillers into the JS matrix and dense or compact nanocomposite films were formed. JS-ZnO and JS-Ag2O nanocomposites with 0.5 wt% ZnO and Ag2O content showed maximum crystallinity i.e. 11.3 and 9.58 %, respectively, as determined by XRD. When compared to the virgin JS film (8.41 MPa), the resultant JS-ZnO-0.5 and JS-Ag2O-0.5 nanocomposites showed significantly enhanced tensile strength (35.7 MPa, 29.2 MPa), elongation at break (15.42 %, 14.62 %) and Young's modulus (141 MPa, 126 MPa), respectively. Also, reduced swelling (120.4 % and 116.1 %) and solubility ratio (17.45 % and 18.42 %) was observed for JS-ZnO-0.5 and JS-Ag2O-0.5 nanocomposites, respectively. Biodegradation results showed that maximum degradation (88 %) was achieved for the JS film within 180 days of soil burial whereas JS-ZnO-0.1 and JS-Ag2O-0.1 nanocomposites showed 78 % and 72 % degradation within 180 days, respectively.

CuO vs. AgO: A comparative study of cathode catalysts for boosting oxygen reduction in microbial desalination cells

Microbial Desalination Cell (MDC) is an innovative approach for water desalination that concurrently produces energy through the process of substrate oxidation. The primary issue of the technique is its limited power on capabilities during the oxygen reduction reaction (ORR). While the depletion of oxygen is a significant process in electrochemical energy conversion, its slow kinetics hinder its utilization in MDCs. One potential resolution to this problem is the utilization of a cathode catalyst with a high level of activity, which effectively enhances the rate of ORR. Different concentrations of copper oxide (CuO) nanoparticles (NPs) were used to investigate the behavior of ORR and its impact on the performance of the MDC. The optimal concentration of silver oxide (AgO) NPs was utilized to conduct a comparative analysis of both types of NPs. The size of CuO NPs and AgO NPs was found to be 65 nm and 55 nm respectively by material characterization studies. The power density achieved in the absence of the catalyst was 1.1 W/m3, and this value increased to 4.9 W/m3 with the incorporation of 3 mg/cm2 AgO. The use of a catalyst loading of 3 mg/cm2 has been determined to be efficacious in enhancing the desalination rate in MDC. The electrochemical investigations conducted also showed an improvement in the electrocatalytic behavior of cathodic kinetics while operating under these specific afterward. Therefore, the utilization of AgO catalyst exhibits potential as a viable option for the expansion of MDC processes, thereby contributing to the achievement of sustainable development objectives.

Nanobiological synthesis of silver oxide-doped titanium oxide bionanocomposite targeting foodborne and phytopathogenic bacteria

Fungi possess remarkable capabilities for metal speciation, dissolution, and mineral formation, which contribute to the production of mycogenic nanostructures. This study explores a green chemistry approach for synthesizing silver oxide-doped titanium oxide (Ag2O-doped TiO2) bionanocomposite utilizing Trichoderma virens. The light yellowish fungal filtrate transformed into a dark brownish colloidal suspension after reacting with silver nitrate and rutile titanium (IV) oxide. X-ray diffractometry (XRD) unveiled the crystalline structure of Ag2O-doped TiO2 bionanocomposite (22.15 nm), showing the coexistence of cubic and rutile tetragonal phases of Ag2O and TiO2, respectively. Fourier-transform infrared spectroscopy (FTIR) showed the presence of functional groups of alcohols, phenols nitro compounds, and aromatic amines derived from the cultural filtrate of T. virens. Raman analysis revealed vibrational modes corresponding to Ag2O and TiO2 nanoparticles. Distinct sharp emission peaks characteristic to Ti, Ag, and O were depicted using energy dispersive X-ray analysis (EDX) analysis. X-ray photoelectron spectroscopy (XPS) confirmed the presence of elemental valence states and binding energies of Ag, Ti, and O in the mycogenic nanocomposite. Field emission scanning electron microscopy (FESEM) revealed aggregation of polydispersed Ag2O-doped TiO2 bionanocomposite, displaying spherical- and cuboctahedron-shaped nanostructures with rough surfaces. High-resolution transmission electron microscopy (HRTEM) showed the presence of circular-, semi-spherical-, hexagonal-, and polygonal-shaped monodispersed Ag2O NPs, with defined boundaries. The Ag2O NPs were obviously deposited on the sheet-like TiO2 NPs. Selected area electron diffraction pattern implied the polycrystallinity of the as-synthesized bionanocomposite. A broad antibacterial spectrum of the prepared bionanocomposite was attained against foodborne pathogenic bacteria; Escherichia coli (12.05 mm), Salmonella enterica (11.26 mm), and Staphylococcus aureus (11.44 mm) and phytopathogenic bacteria; Clavibacter michiganensis subsp. michiganensis (15.72 mm), C. michiganensis subsp. capsici (10.80 mm), streptomycin-sensitive and -resistant Xanthomonas citri pv. citri (14.11 and 14.53 mm, respectively), and streptomycin-sensitive and -resistant Pectobacterium carotovorum subsp. carotovorum (11.36 and 11.07 mm, respectively) using in vitro Kirby-Bauer method. Minimum inhibitory and minimum bactericidal concentrations were determined via a broth micro-dilution assay. FESEM revealed significant morphological alterations in bacterial cells upon treatment with the Ag2O-doped TiO2 bionanocomposite, including deformed shape, rough surface, cell thinning, wrinkled cell wall, protrusions, cavitations, and cracks. These findings signify the successful mycosynthesis of Ag2O-doped TiO2 bionanocomposite, which acted a potent antibacterial agent against a variety of foodborne and phytopathogenic bacteria, which could be employed for environmental, biomedical, agricultural, food bio-processing applications.

Hybrid nanocomposites for enhanced photodetection: Synthesis and application of Ag2O@Graphene/Si heterojunctions

Thin silver oxide graphene (Ag2O@G) nanocomposite films were synthesized via facile spray pyrolysis and integrated into heterojunction architectures with silicon substrate. Structural characterization confirmed the successful anchoring of crystalline Ag2O nanoparticles uniformly over graphene layers with strong interfacial coupling. Optical analysis showed synergistic tuning of the band structure by hybridization, which improves light absorption. Electrical measurements showed rectification behavior of the diode and an increase in photocurrent up to milliamperes under illumination. A response time of 350 ms, a recovery time of 400 ms, stability over repeated cycles and exceptional values such as 0.39 A/W responsivity, 88 % external quantum efficiency and 4×1011 Jones detectivity at 600 nm were achieved. The nanocomposite heterojunctions utilize the superior charge mobility of graphene with the bandgap tuning of Ag2O, enabling efficient light harvesting, photogeneration, and ambipolar charge separation and transport across the multifunctional interface. Customized Ag2O@G heterostructures represent a promising material platform to drive advances in high performance photodetectors, image sensors, night vision devices and photovoltaics through the engineering of morphology, crystallinity and interfaces.

Garlic Cellulosic Powders with Immobilized AgO and CuO Nanoparticles: Preparation, Characterization of the Nanocomposites, and Application to the Catalytic Degradation of Azo Dyes.

Nanomaterials have attracted specific consideration due to their specific characteristics and uses in several promising fields. In the present study, Chondrilla juncea was employed as a biological extract to facilitate the reduction of copper and silver ions within garlic peel powders. The resulting garlic-CuO and garlic-AgO nanocomposites were characterized using several analytical methods including FTIR, TGA/DTG, SEM, TEM, and XRD analyses. The garlic peel exhibited a rough surface. The nanoparticles were evenly dispersed across its surface. The incorporation of CuO and AgO nanoparticles affected the crystal structure of garlic peel. The establishment of CuO and AgO nanoparticles was evidenced by the highest residual mass values observed for the prepared nanocomposites. The thermogravimetric analysis showed that the prepared nanocomposites had lower thermal stability compared with garlic peel powders. The prepared nanocomposites were used for catalytic degradation of naphthol blue black B and calmagite. The decolorization process depended on the quantity of H2O2, initial concentration of azo dyes, duration of contact, and temperature of the bath. The calculated activation energy (Ea) values for the garlic-CuO nanocomposites were found to be 18.44 kJ mol-1 and 23.28 kJ mol-1 for calmagite and naphthol solutions, respectively. However, those calculated for garlic-AgO nanocomposites were found to be 50.01 kJ mol-1 and 12.44 kJ mol-1 for calmagite and naphthol, respectively.

In situ alkali‐free growth of octahedral Ag2O nanoparticles by bacterial cellulose for efficient antibacterial application

AbstractUniform octahedral Ag2O nanoparticles were in situ synthesized within natural bacterial cellulose (BC) films without any inorganic alkali. The morphological transformation of Ag2O from nanoparticles and small nanoplates to an octahedral structure was well controlled by varying the UV exposure time. To reduce and anchor Ag2O nanoparticles, abundant hydroxyl groups on the surface of natural BC fibers ensured an ideal environment for the mild redox reaction between Ag+ and –OH groups. The structural features and structure–activity relationship of Ag2O/BC films were confirmed through TEM, energy dispersive spectroscopy assisted SEM analysis, Fourier transform IR, X‐ray photoelectron spectroscopy, TGA and XRD. The structure–antibacterial activity relationship of the Ag2O/BC films was proved against both Gram‐positive (Staphylococcus aureus) and Gram‐negative (Escherichia coli) bacteria. They also showed excellent performance in the photocatalytic degradation of organic dyes. Ag2O/BC films have potential bactericidal applications in the field of pharmacy, specifically for wound dressing and flexible wearable materials. © 2024 Society of Chemical Industry.

Unveiling the industrial photocatalytic dye degradation of textile effluents using tailored eco-friendly AgO Nanoparticles

<p>In this study, tamarind leaf extract was used to effectively produce silver oxide (AgO) nanoparticles. Crystal violet (CV), Alizarin red (AR), Reactive black (RB), and rhodamine b (Rh B) degradation were examined to evaluate the effectiveness of AgO NPs. XRD patterns, UV-visible spectroscopy, Fourier transform infrared spectroscopy, and scanning electron microscope was used to analyze the AgO NPs. SEM observations showed spherical morphology size ranging at an average of 58.17 nm. Silver and oxygen were the only elements in the nanostructure, as shown by EDS chemical maps. The synthetic silver nanostructure, with a crystal size of 38 nm, was verified by X-ray diffraction to have the usual cubic structure. The nanostructure showed degradation efficiencies in Crystal violet, Alizarin red, Reactive black, and Rhodamine B, indicating excellent degradation efficiency. All of these results point to the effective production of AgO NPs without the use of any hazardous chemicals, and they point to this material as a potentially beneficial substance for eliminating toxic dye from wastewater made by commercial colouring processes.</p>

Unveiling the industrial photocatalytic dye degradation of textile effluents using tailored eco-friendly AgO Nanoparticles

Unveiling the industrial photocatalytic dye degradation of textile effluents using tailored eco-friendly AgO Nanoparticles

Impact of Nanoparticle Additions on Life Cycle Assessment (LCA) of Ceramic Tiles Production.

The ceramic tile industry, with significant energy and material demands in its manufacturing processes, has employed technological innovations in energy efficiency, advanced equipment and tile thickness reduction to address these challenges. This study aimed to assess the impact of Ag2O, CuFe2O4, Fe3O4, and SiO2 nanoparticles (0%, 1%, and 5% by weight) on the mechanical strength, water absorption, and apparent thermal conductivity of ceramic tiles, as well as their capacity to reduce energy and raw material consumption. This reduction translates into a decrease in environmental impacts, which have been evaluated through life cycle assessment (LCA) methodology applied to the manufacturing processes. Nanoparticles (Ag2O, CuFe2O4, Fe3O4, and SiO2) were initially screened on TF clay (0%, 1%, 5% w/w), and the most effective were applied to CR1 and CR2 clays (0%, 1%, 5% w/w). Findings indicated a 32% increase in temperature gradient and a 16% improvement in flexural strength with the addition of Fe3O4 nanoparticle at 1% (w/w) in TF clay. Furthermore, there was a potential 48% reduction in energy consumption, and up to 16% decrease in tile weight or thickness without affecting the flexural strength property of the test tiles. LCA results demonstrated that the addition of Fe3O4 nanoparticle has potential reductions of up to 20% in environmental impacts. This study suggests that nanoparticle addition offers a viable alternative for reducing energy and material consumption in the ceramic tile industry. Future research should focus on assessing the economic impact of transitioning to a sustainable business model in the ceramic tile industry with nanoparticles addition.