Agno3 Lab Report

Photoluminescence (PL) spectra of the as-prepared samples were investigated to understand the transfer, separation, and recombination of photo-generated electrons and holes pairs [34]. In general, lower PL intensity indicates a lower recombination rate of charge carries, leading to higher photocatalytic activity [35]. The room temperature PL spectra (excitation at 330 nm) of ZnO and Ag@ZnO CSNS are depicted in Fig. 4. It has been observed that ZnO shows a near band edge emission band centered at 378 nm and no emission band in the visible region. In the case of Ag@ZnO CSNS, the intensity of PL spectrum is significantly lowered compared to that of the ZnO. The distinct quenching of the emission was distinctly observed from the Ag@ZnO CSNS,

Synthesis of OA-Ag NPs: For the preparation of OA-stabilized Ag NPs [39], silver trifluoroacetate (0.4 g), OA (3.5 mL), and isoamyl ether (30 mL) were mixed in a 250 mL three-neck flask under argon. The mixture was heated at 160 °C for 30 min then cooled to room temperature by removing the heat source. The purification process was performed four times using excess polar solvent (ethanol) and centrifugation. The precipitated OA-Ag NPs were dispersed in

Photocatalysis is one of the clean and renewable technologies, utilizes naturally enormous abundant, clean and safe solar power. The cheap solar energy harnessing is one of the most exciting features to gain significant attention toward photocatalysis direction. Titanium oxide-based photocatalyst has shown considerable interest since the discovery because of the excellent properties such as chemical and photostability, eco-friendly nature and high catalytic reactivity.2,3 TiO2 photocatalysts have been widely engaged in various photocatalytic applications such as water and air cleaning, self-cleaning and anti-fogging TiO2 coated glasses, tiles, and shelters. TiO2 only generates electron-hole pairs under UV light, which are responsible for the photocatalytic reaction. There are numerous investigations have been done to alter the TiO2 structures to absorb visible lights. The strategy includes adding noble metals4, cations5, non-metals6, and metal oxides7 through various methods such as sol-gel8, physical ion-implantation methods,

Silver nanoparticles were synthesised using a simple method described by Hiramatsu [Hir01]. For the

The association of metal nanoparticles and antibiotics is a very promising area of research. Silver nanoparticles are interesting when compared with silver ions due to their larger size, in turn, improves the capacity to react with several molecules. The bactericidal action of silver nanoparticles and amoxicillin was investigated using E. coli and silver nanoparticles of 20 nm in size (prepared by reducing an aqueous solution of AgNO3 with a freshly prepared aqueous ascorbic acid solution and ammonia). Microbiological tests

Ag ions can also interference with DNA replication processes by interact with phosphorus group, which stops bacterial proliferation and decreases the number of cells over time (Wong and Liu, 2010) and (Cao et al., 2010). Moreover, Samberg et al., 2011 proposed that the antibacterial activity of Ag ions is caused by the synergistic effect between the binding of silver ions to the cell wall, their uptake and subsequent accumulation in the cell, and their interference with critical biomolecules within the cell.

Silver nitrate is an inorganic compound with chemical formula AgNO3. It's colorless or white crystalline solid which is less sensitive to light than the halides and a highly water soluble crystalline. It was once called

Nanomaterials have some neuro-toxicity including short-term memory reduction and learning ability decreasing[6]. Also, it was reported that the prenatal exposure to nanoparticles can effects on neurobehavioral development[7] via ROS augmentation in hippocampus[8]. In particular, females are more prone to nanoparticle diverse effects as their toxicity may lead to impairment of reproductively and fetal development[9]. Ag-NPs, in perticular, can pass blood brain barrier (BBB) so, they can accumulate in the brain[10]. Also it was shown that even in low concentration, silver has long maintenance time in brain than the other tissues[11]. Furthermore, Ag-NPs retention time in mouse body was more than 4 months. These findings provide enough time for Ag-NPs to affect on neural cells natural physiology and development. It was recorded that Ag-NPs pass from placenta, as a vital barrier, so it causes neurotoxicity in the fetus[12], [13]. Also some studies reported that Ag-NPs are accumulated in fetuses tissues by passing from placenta[14]. But still little information is available associated to the relation between prenatal Ag-NPs exposure and following behavioral performance. Various application in medicine, passage from the placenta and following that passing from the BBB, long maintaining and long retention time come to consideration this

The characteristics of the disc surface affect the flow patterns generated on the film as well as the residence time of the reactants film. The effect of disc texture on particle characteristics is depicted in Figure 7 and Figure 8. It can be seen that using the grooved disc surface results in smaller particle size and narrower particle size distribution as compared to smooth disc surface. A narrow particle size distribution for the production of silver nanoparticles was achieved by Iyer et al.[43] using the grooved disc. The authors postulated that that the corrugated nature of the grooved disc promoted shear induced micromixing of the thin film on the disc at higher rotational speed. The efficient micromixing ensured that all the particles were exposed to the similar conditions to maintain a narrow size distribution [43]. Similar enhancement effects of grooved surfaces have been reported for styrene polymerisation in the SDR [9]. It has also been suggested in the literature that surface textures have the potential to suppress liquid channelling or rivulet flow compared to a smooth surface under identical conditions of liquid flowrate and liquid properties so that a higher wetted area is achieved [44]. Rivulet flow as opposed to film flow would result in larger average film thicknesses which may lead to detrimental performance, especially under strictly laminar flow conditions (i.e. where any surface wave-induced turbulence is absent). Thus, the intensifying effects of the

Ternary nanocomposites (NCs) comprising Ag-Cu2O supported on reduced graphene oxide (rGO) with enhanced stability and visible light photocatalytic activity were synthesized via a facile and green approach using Benedict’s solution and glucose solution at room temperature without the need of any toxic reagent, surfactant or any special treatment. Besides mild reducing capability to GO, glucose also induces the functionalization of rGO sheets, preventing the aggregation of the reduced sheets and providing a site for the stabilization of Cu2O. Further, the reaction time for the synthesis of Ag-Cu2O/rGO NCs was significantly controlled by varying the concentration of Benedict’s and glucose solution. The photocatalytic efficiency of the

Figure 3 shows dispersion of untreated, APS, FHES and TMSO treated TRNPs in different solvents after centrifuging at 1000 rpm for 15 minutes. After centrifuging, if most of the particle settles down it is an indicator of poor dispersion of the particle in the solvent. When the relatively large particles settles down and small particles remains in the suspension it is an indicator of medium dispersion. If all the particles remains in the solvent and no precipitation is found it is an indicator of very good dispersion. From Figure 3 it is found that, untreated TiO2 is best dispersed in DMF and DMAc polar aprotic solvent which is also supported from small Z average diameter and acceptable PDI value. For untreated NP medium dispersion is found in DI water and ethanol and poor dispersion in TCB, Toluene, DCM, choloroform, THF and isopropanol. As the untreated TRNP is hydrophilic in nature the particles tends to disperse well in relatively polar solvent. APS treated titania nanoparticle renders hydrophobic behavior to the surface [20] and essentially doesn't dissolve in DI water, DMF and DMAC etc. highly polar solvent. The best solvent for APS modified titania is ethanol, isopropanol and formic acid which is conspicuous both from digital image and small mean diameter value of the nanoparticle. Due to the presence of -NH2 functional group at the end of organic surface of APS treated TRNPs the hydrogen bonding force is the dominant dispersion force. As a result, APS treated NPs

In the present work, PVA-Ag nanocomposite films with thickness 0.18 mm, constant silver content (0.4 wt. %) and different time of reactions (0.1, 3, 5, 7, 9 h) were prepared by chemical reduction methods. Surface topology, optical and electrical properties of PVA-Ag nanocomposite were studied using absorption spectroscopy, electrometer, atomic force microscope (AFM) and photoluminescence (PL) spectroscopy were used to characterize the prepared nanocomposites. Optical absorption coefficient studies showed a peak at 427 nm for all samples, in addition to the peak at 200 nm for undoped PVA film. There is observable change in the absorbed intensity at 427 nm with the time of reaction. The refractive index was found increase with increasing the time of reaction. It was found that the root mean square (RMS) roughness. Frank-poole emission is the prevailing transport mechanism for all samples. While PL intensity at 427 nm increase as the time of reaction is increased.

In the present work, PVA-Ag nanocomposite films with thickness 0.18 mm, constant silver content (0.4 wt. %) and with different time of reaction (0.1, 3, 5, 7, 9 h) were prepared by chemical reduction method. Structure, surface topology, photoluminescence and electrical properties of PVA-Ag nanocomposite were studied using x-ray diffraction (XRD), electrometer, atomic force microscope (AFM) and photoluminescence (PL) spectroscopy were used to characterize the prepared nanocomposites. X-ray patterns showed the existence of Ag-nanoparticles within the PVA polymeric matrix with face centered cube (FCC) phase. It was found that the PL intensity for all samples increases, while the root mean square (rms) roughness decreases as the time of reaction is increased. Current-voltage characteristics were analyzed to explore carrier transport mechanisms in Ag-PVA nanocomposite and the results showed that there is an improvement in the electrical conductivity of the PVA-Ag films and Frank-poole emission is the prevailing transport mechanism for all samples.

In the present work, PVA-Ag nanocomposite films with thickness 0.18 mm, constant silver content (0.4 wt. %) and different time of reactions (0.1, 3, 5, 7, 9 h) were prepared by chemical reduction methods. Surface topology, optical and electrical properties of PVA-Ag nanocomposite were studied using absorption spectroscopy, electrometer, atomic force microscope (AFM) and photoluminescence (PL) spectroscopy were used to characterize the prepared nanocomposites. Optical absorption coefficient studies showed a peak at 427 nm for all samples, in addition to the peak at 200 nm for undoped PVA film. There is observable change in the absorbed intensity at 427 nm with the time of reaction. The refractive index was found increase with increasing the time of reaction. It was found that the root mean square (RMS) roughness. Frank-poole emission is the prevailing transport mechanism for all samples. While PL intensity at 427 nm increase as the time of reaction is increased.

Silver nanoparticles were biosynthesized via a green route using 10 different plants extracts and formed AgNPs were tested against drug resistant microbes and their biofilms. These nanoparticles were characterized using UV- vis spectroscopy and TEM which confirmed their synthesis, shape and size. FTIR clearly demonstrated the presence of the bio-groups on the surface of AgNPs. XRD confirmed the crystalline structure of AgNPs. TEM images were further analyzed using Image J software which showed that majority of particles were under 100 nm and majorly distributed over 1 to 60 nm size range. Their antimicrobial efficacy was checked against bacteria harboring antibiotic resistance genes like CTX-M-3, CTX-M-15, OXA-1, arm A, SHV-1 and NDM-1 in gram negative bacteria and fluconazole, amphotericin B and itraconazole resistant genes in fungus. Gram positive bacteria and fungi Candida albicans were inhibited at higher MICs values in comparison to Gran negative bacterial strains. The result indicated that these particles were antibacterial in nature without