Silver Phosphate Research Articles

Preparation of the floating HGMs-Ag3PO4 composites and the visible-light photocatalytic properties

The hollow glass microspheres (HGMs) with low density were used as the support to obtain the floating visible-light photocatalysts (HGMs–Ag3PO4) composites, in which silver orthophosphate (Ag3PO4) was dispersed on the surface of HGMs via silane coupling agents. The morphology, crystal structure and optical property of the HGMs-Ag3PO4 composites were characterized and the contents of Ag3PO4 dispersed on the surface of HGMs were quantified by atomic absorption spectrometry (AAS). Methylene blue (MB) was selected as the typical organic pollutants to evaluate the photocatalytic activity of HGMs-Ag3PO4 composite photocatalysts. The photo-catalytic rate of the floating composites was larger than the sinking composites and even pure Ag3PO4. Ag3PO4 particles could be dispersed well on the HGMs. The floating composites has a larger light contact area and the increased photo-catalytic activity sites even at the low Ag3PO4 loading. This work may open up a new insight for the floating photocatalyst to degrade organic dye on account of the low density and high visible-light responsiveness.

Structure and dielectric properties in silver phosphate AgPO3 glass–ceramic

Silver phosphate glass 50Ag2O-50P2O5 was elaborated by the conventional quenching method. The glass was found colorless and its amorphous state was verified using X-ray diffraction. Raman spectroscopy is used to characterize the structural approach of this silver phosphate glass. This technique allowed the identification of several structural units of phosphate, mainly metaphosphates. The crystallization behavior of the glass was made by heat treatment to achieve the glass–ceramic. X-ray diffraction (XRD) of the glass–ceramic revealed the formation of AgPO3. Investigation of its dielectric properties is undertaken in the range frequency 1 Hz–1 MHz and at various temperatures.

Preparation, characterization and electrical studies of polymer composite solid electrolyte (1-x) polyaniline-Ag3PO4. x Al2O3

Polymer solid electrolytes comprise of a polymer which serves as a backbone and provides the surface for the transport of electrolyte ions, and an ionic salt. In the present work, polymer composite solid electrolyte comprising of Polyaniline (PANI) as polymer and silver phosphate (Ag3PO4) using alumina (Al2O3) as filler of different compositions having the formula (1-x) PANI-Ag3PO4. x Al2O3 with x ranging from 0.0 to 0.6 was prepared by solid state reaction method. The structural elucidation and characterization was done by X- Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric- Differential Thermal Analysis (TG-DTA), Scanning Electron Microscopy (SEM) and Impedance Spectroscopy. The conductivities recorded over a temperature range of 40-250° C lie in the range of 10-3 to 10-5 S cm-1. Maximum conductivity σ = 5.72×10-3 S/cm. was seen in the composition x = 0.2 at 513 K, with an activation energy of 0.16 eV

Improving the photocatalytic activity of silver orthophosphate by thermal annealing for photocatalytic degradation of β-naphthol

Improving the photocatalytic activity of silver orthophosphate by thermal annealing for photocatalytic degradation of β-naphthol

Highly luminescent and ultrastable cesium lead bromide perovskite patterns generated in phosphate glass matrices.

Owing to their exceptional optoelectronic properties, all-inorganic lead halide perovskites offer enormous potential for next generation photonic, light-emitting, and optoelectronic devices. However, their usage is significantly limited by their poor stability upon moisture exposure and lead toxicity issues. Moreover, many of the aforementioned applications rely on the development of confined perovskite patterns of various shapes and periodicities. Here we report a simple and low-temperature method enabling the controlled incorporation of photoluminescent all-inorganic metal halide PNCs into a silver phosphate glass (AgPO3) matrix which is transparent in most of the visible range. The developed fabrication protocol is based on a simple melting encapsulation process in which pre-synthesized perovskite crystals are inserted in the glass matrix, following the initial glass quenching. Using this novel approach, two types of composite perovskite glasses are prepared, one that hosts perovskite isles and the second in which a thin perovskite layer is embedded beneath the glass surface. Both types of composite glasses exhibit remarkable photoluminescence stability when compared to the ambient air-exposed perovskite crystals. More importantly, by means of a simple and fast cw-laser processing technique, we demonstrate the development of encapsulated dotted perovskite micropatterns within the composite perovskite glass. The ability of the proposed system to resolve stability and lead toxicity issues, coupled with the facile formation of highly luminescent perovskite patterns pave the way towards the broad exploitation of perovskite crystals in photonic applications.

Bioactive silver phosphate/polyindole nanocomposites.

Materials capable of releasing reactive oxygen species (ROS) can display antibacterial and anticancer activity, and may also have anti-oxidant capacity if they suppress intracellular ROS (e.g. nitric oxide, NO) resulting in anti-inflammatory activity. Herein we report silver phosphate (Ag3PO4)/polyindole (Pln) nanocomposites which display antibacterial, anticancer and anti-inflammatory activity, and have therefore potential for a variety of biomedical applications.

Agro-waste extracted cellulose supported silver phosphate nanostructures as a green photocatalyst for improved photodegradation of RhB dye and industrial fertilizer effluents.

The efficiency and reusability of photocatalysts are the dominant factors for their pragmatic use. The visible light induced semiconductor silver phosphate is a superior photocatalyst effective under visible light but its stability is still an undiscussed issue. To overcome this stability issue in this present manuscript, eco-friendly agro-waste extracted cellulose supported silver phosphate nanostructures have been designed for the first time through a simple chemical process. At first, silver phosphate nanostructures were synthesized by the co-precipitation method. Then, different weights of cellulose were added to the silver nitrate solution to form cellulose supported silver phosphate nanostructures. The photodegradation efficiency for each weight ratio was examined in which the photocatalyst Ag-8 nanostructures showed a high rate (0.024 min−1) for degradation of Rhodamine B (RhB) using a low intensity tungsten bulb. Real sample analysis has also been carried out using this photocatalyst for the degradation of industrial fertilizer effluents. The degradation rate of all the nanostructures was found to be high in comparison to pristine silver phosphate as well as the extracted bare cellulose. The photocatalytic activity is enhanced because of the participation of cellulose as a support which makes an interface for silver phosphate and assists it in delaying the charge recombination period under visible light. To understand the photochemical reaction of electrons and holes, scavenger studies were also performed.

Colorimetric sensing of chlorpyrifos through negative feedback inhibition of the catalytic activity of silver phosphate oxygenase nanozymes.

Intensive use of organophosphate chlorpyrifos pesticides in farming has become a serious issue due to their harmful effects on living beings. Most fruits, vegetables and soil contain chlorpyrifos, and it cannot be rinsed out completely by water washing. Therefore, a selective and sensitive detection of chlorpyrifos is significant. In the present study, the intriguing oxidase-mimicking activity of Ag3PO4 nanoparticles (NPs) is explored for the fast and selective detection of chlorpyrifos pesticides. Ag3PO4 NPs exhibit several advantages, such as great catalytic efficiency, high stability, monodispersity and reusability, over other expensive nanozymes via a facile one-step sensing. The size, shape, crystal planes and diffraction patterns of the Ag3PO4 NPs were observed via FESEM and HR-TEM. The surface properties and oxidation states were analyzed via XPS technique. Ag3PO4 NPs possess intrinsic excellent oxidase-mimicking properties against 3,3′,5,5′-tetramethylbezidyne (TMB). When chlorpyrifos and Ag3PO4 NP nanozymes come in proper orientation proximity, chlorpyrifos is oxidized. The oxidized chlorpyrifos produces sulfide ions and chlorpyrifos oxon. The produced sulfide ions in the reaction system interact with Ag3PO4 NPs and inhibit their catalytic activity by feedback inhibition. Indeed, neither any catalytic site is left to oxidize TMB nor any blue colour appears. Thus, this feedback inhibition phenomenon senses chlorpyrifos pesticides. The calculated limit of detection (LOD) for the standard chlorpyrifos is ∼9.97 ppm, and the efficacy of the Ag3PO4 NPs calculated in terms of the Km value was found to be 0.15 mM. A real sample analysis was carried out by the standard addition method with two soil samples collected from Pethapur and Chiloda villages.

Evaluation of Silver Diamine Fluoride as Indirect Pulp Capping Agent in Primary Teeth: An in vivo Study

Background and Aimnbspnbspnbspnbspnbspnbsp Indirect pulp capping IPC preserves the pulp vitality by disinfecting and re-mineralizing remaining carious dentin.Calcium hydroxide has been considered as a gold standard for pulp capping. Silver diamine fluoride SDF has been used as a cariostatic agent and deposits silver phosphate to restore mineral content resulting in re-hardening of tooth. The study was done toevaluate and compare effects of SDF with calcium hydroxide as an IPC agent in primary teeth.Methods 34 primary anterior and posterior teeth were selected from 27 patients aged 4-10 years. Samples were randomly divided into two groups Group 1 experimental - 38 SDF Group 2 control - Dycal. After caries removal test materials were applied at the base of the cavity followed by restoration with glass ionomer cement. Clinical and radiographic follow up were done at 1 week and 1 month intervals. Results Clinical and radiographic success at 1 month was found to be 100 in SDF and 93.75 in calcium hydroxide with no significant difference between two groups. Conclusion Results of the present study indicated that SDF can be used as potential substitute to Calcium hydroxide for IPC in primary teeth.

Hydrothermal sterilization in silver nitrate solution endows plasma sprayed hydroxyapatite coating with antibacterial property

Plasma sprayed hydroxyapatite (HA) coatings are widely used on bone implants due to excellent osteoconductivity. However, the coating also provides an appropriate environment for biofilm formation. To prevent bacteria adhesion, this study tried to modify the HA coating with silver (Ag) by hydrothermal sterilization in dilute silver nitrate (AgNO3) solution at 121 °C for 20 min. Surface morphology, phase and chemical composition and antibacterial ability of the sterilized coating were investigated. After treatment, Ag was successfully incorporated onto the HA coating surface as in situ growing silver phosphate (Ag3PO4) compound and the distribution of Ag element was homogeneously. Inhibition zone test showed that, the sterilized HA coating had an excellent antibacterial ability against Staphylococcus aureus (S. aureus). This simple and feasible method shows promising potential for clinical applications.

Enhanced visible light-driven photocatalytic performance and stability of Ag3PO4 by simultaneously loading AgCl and Fe(III)

Silver phosphate (Ag3PO4) is widely used in the field of photocatalysis due to its excellent quantum efficiency and high photocatalytic activity. With Ag3PO4 as the precursor, we have prepared a ternary composite of Ag3PO4/AgCl/Fe(III) through an in-situ anion-exchange and impregnation method by using ferric chloride as the sources of chlorine and iron. The characterization results indicated that AgCl and Fe(III) were successfully loaded onto the surface of Ag3PO4 without any changes in its morphology and crystal structure. A significantly enhanced photocatalytic performance for the degradation of tetracycline (TC) was obtained under visible light irradiation (>420 nm). The degradation rate of TC over Ag3PO4/AgCl/Fe(III) (0.458 min−1) was 2.32 times and 2.94 times that of Ag3PO4/AgCl (0.197 min−1) and the pure Ag3PO4 (0.156 min−1), respectively. Furthermore, the stability of the photocatalyst was also improved. On one hand, the presence of AgCl could prevent Ag3PO4 from dissolution due to the smaller solubility of AgCl. On the other hand, the heterostructure and Fe(III) in Ag3PO4/AgCl/Fe(III) could promote the transfer and the separation of photoexcited electrons and holes, thus enhancing the photocatalytic activity. Our investigation might give some new insights for the facile preparation of photocatalysts with high visible light-driven photocatalytic performance.

Electrochemical Scaffold Based on Silver Phosphate Nanoparticles for the Quantification of Acetaminophen in Body Fluids and Pharmaceutical Formulations

Herein, we present the electrochemical scaffold for the quantification of acetaminophen (ACAP) using a silver phosphate nanoparticle (Ag–P NP) fabricated screen-printed carbon electrode (SPCE). The...

Binary co-deposited mixtures of silver and magnesium phosphates and silver and copper(II) phosphates

Binary co-deposited mixtures of silver and magnesium phosphates and silver and copper(II) phosphates

Ag3PO4-Red Banyan Fruit Extract (Ficus benjamina. L) Nanocomposite for Degradation of Detergent Waste

Detergents waste containing SDS (Sodium Dodecyl Sulfate) still becomes a major environmental problem that must be overcomed. The degradation of SDS by silver phosphate (Ag3PO4)-Red Banyan extract nanocomposite was performed under visible light. This research aimed to determine the percentage decrease in SDS concentration under visible light by using Ag3PO4 facilitated extract of red banyan fruit. The Ag3PO4-Red Banyan extract nanocomposite was prepared by coprecipitation method and facilitated by a red banyan extract solvent. The result showed that the silver composite phosphate (Ag3PO4) facilitated red banyan extract had a percentage of SDS degradation i.e. 85.9% for 2 hours. This result showed that the silver composite phosphate (Ag3PO4)-a red fruit extract becomes a promising ingredient for degrading SDS in aquatic environment environments.

Gama-graphyne as photogenerated electrons transfer layer enhances photocatalytic performance of silver phosphate

γ-graphyne (γ-G), as a new kind of 2D carbon allotrope that consists of sp- and sp2-hybrid carbon atoms, has great potential in the development of highly efficient photocatalytic systems because of its unique properties. In this study, novel photocatalysts Ag3PO4@γ-G with excellent photocatalytic activity and photostability were successfully synthesized by a facile preparation method. The density functional theory (DFT) calculation results of Ag3PO4@γ-G composite, including the band charge density distributions, three-dimensional charge density difference and planar average electrostatic potential, indicated the successful construction of electrons transfer layer in Ag3PO4@γ-G composite. The photogenerated electrons of Ag3PO4 can be rapidly transferred to the γ-G under the driving of built-in potential well, which leads to the high separation efficiency of photogenerated carriers and greatly improves the photocatalytic performance of catalysts. The photocatalytic degradation rate of norfloxacin (NFL), 2-Hydroxynaphthalene (2-HNP) and phenol over the binary composite catalyst could reach 100 % only after 8, 5 and 16 min of visible light irradiation respectively, and the apparent rate constants of which were 15.3, 9.6 and 19.7 times higher than that of the pure Ag3PO4 respectively. The analyses of LC–MS and 3D EEMs showed that the 2-HNP and NFL mainly degraded into short-chain carboxylic acids. The results of free radical quenching experiment and ESR characterization suggested that all kinds of active species worked in the degradation process, while the photogenerated holes and superoxide radicals played a dominant role. The novel addition of γ-G and the construction of electrons transfer layer in photocatalysts provide a new strategy for the design of efficient environmental remediation catalysts.

Photocatalytic performances of heterojunction catalysts of silver phosphate modified by PANI and Cr-doped SrTiO3 for organic pollutant removal from high salinity wastewater

In this work, Ag3PO4/PANI/Cr:SrTiO3 photocatalysts were designed to effectively eliminate organic pollutants including Rhodamine B and phenol from high salinity wastewater under visible light. The phase composition, optical properties, and morphology of powders were studied, and the effects of inorganic salts on removal performance of the as-prepared particles were also tested. Results showed that the photocatalytic activities of Ag3PO4/PANI/Cr:SrTiO3 composites for Rhodamine B and phenol reached 100% within 10 min and 18 min, respectively. The reaction rate of pure Ag3PO4 was 7 times less than that of the ternary composite with the adding of PANI and Cr:SrTiO3. The activity of Ag3PO4/PANI/Cr:SrTiO3 remained at 92.25% after five cycles, so the photocatalytic and recyclable performance of ternary composite was greatly improved. In addition, when there was SO42− with a content of ranging from 1% to 21%, the degradation activity of the ternary catalyst under visible light was not changed for Rhodamine B, which indicated that the ternary catalyst exhibited the excellent sulfate resistance ability. Results from ESR and radical trapping experiments showed that O2− and h+ made an important contribution to visible-light photocatalytic activities.

A promising inorganic-organic Z-scheme photocatalyst Ag3PO4/PDI supermolecule with enhanced photoactivity and photostability for environmental remediation

Silver orthophosphate (Ag3PO4) based semiconductor photocatalysis have been widely investigated for environmental purification due to its strong oxidation ability. Yet, its poor photostability and low photoactivity hamper its extensive applications. Here, an inorganic-organic Z-scheme photocatalytic system for antibiotic degradation demonstrated high photoactivity and stability through the use of Ag3PO4/Perylene diimide organic supermolecule (PDIsm). The apparent rate constant of tetracycline hydrochloride (TC-H) degradation with Ag3PO4/PDIsm was 1.5 times that of Ag3PO4 and 8 times that of PDIsm. The photocatalytic activity of Ag3PO4/PDIsm toward TC-H still kept 65 % after four reuses, while pure Ag3PO4 only kept 22 %. We revealed that this high photoactivity and photostability arisen from the efficient carriers separation and the formation of direct Z-scheme junction. Importantly, this Z-scheme electron transfer pathway was confirmed by thorough experimental study and density functional theory (DFT) calculation. This work demonstrated the significant potential of Ag3PO4-based inorganic-organic Z-scheme photocatalyst in environmental remediation.

Адсорбция наночастиц серебра на моно-и полифиламентных волокнах

The adsorption of Ag-containing solutions and gel compositions on modern natural and artificial fibers, as well as polyfilament yarns with different coatings, was evaluated. It is determined that the fibers of natural origin are characterized by the highest degree of adsorption. In addition, the developed gel composition based on silver nanoparticles also demonstrates high adsorption on the combined suture material with a chemically inert coating (for example, silicone). The distribution of silver nanoparticles on the suture material “Polyester” was accompanied by a significant predominance (up to 76%) of their sizes in the range from 1 to 5 nm. It was also found that silver nanoparticles that are part of the “Argogel” preparation can be effectively adsorbed by various suture materials, especially when they are exposed to “Sabfil” (up to 36%) and “Dexon” threads (up to 38%). The use of synthesized Ag-gel containing silver nanoparticles obtained by the method of cavitation-diffusion photochemical reduction allows, after 1 hour of exposure, to achieve a significant (up to 14%) degree of absorption of these nanoparticles on the surface of the suture material, including “Catgut” and “Dexon”, with a decrease in the subsequent aggregation of sorbed nanoparticles. It has been determined that although the components of the suture material do not lead to the inactivation of silver ions, there is still a high probability of their binding to various ions with the formation, above all, of insoluble silver chloride and phosphates in the wound discharge.

The carboxylate magnetic – Zinc based metal-organic framework heterojunction: Fe3O4-COOH@ZIF-8/Ag/Ag3PO4 for plasmon enhanced visible light Z-scheme photocatalysis

In this work, magnetic nanoparticles (MNPs) grafted with carboxylic acid (Fe3O4-COOH MNPs) were successfully prepared from incorporation of glutaric anhydride as a functional group on the surface of the ferrite NPs. The MNP was used as a template to induce the growth of ZIF-8 metal–organic framework (MOF) on its surface. The Fe3O4-COOH@ZIF-8 core-shell was incorporated with silver phosphate (Ag3PO4) and Ag nanoparticles (Ag NPs) to develop a visible light active Fe3O4-COOH@ZIF-8/Ag/Ag3PO4 photocatalyst. The materials were characterized using a range of techniques. The photocatalytic activity was investigated systematically by degrading an organo-phosphorus pesticide, diazinon under visible light irradiation. Among synthesized samples, the Fe3O4-COOH@ZIF-8/Ag/Ag3PO4 heterostructured system exhibited highest photocatalytic activity and improved stability compared to others for the degradation of diazinon under visible light. The superior activity and improved stability of this heterostructured photocatalyst was attributed to the synergistic effects from surface plasmon resonance (SPR) of Ag NPs and sequential energy transfer via Z-scheme mechanism, for effective separation of electron-hole pairs. Radical-trapping experiments demonstrate that holes (h+) and O2− are primary reactive species involved in photocatalytic oxidation process. Moreover, the Fe3O4-COOH@ZIF-8/Ag/Ag3PO4 photocatalyst did not show any obvious loss of photocatalytic activity during five cycle tests, which indicate that the heterostructured photocatalyst was highly stable and can be used repeatedly. Therefore, the work provides new insights into the design and fabrication of metal-organic frameworks (MOFs) for use as a visible light photocatalyst for degrading organic contaminants.

Photodegradation of organic pollutants in wastewater with different morphologies of silver phosphate nanocatalysts

Photocatalyst can use the sunlight to photodegrade the environmental pollutants. In this article, AgNO3 and Na2HPO4 were used as raw materials to prepare different morphology Ag3PO4 nanocatalyst with different methods. They are solid phase method, hydrothermal method, conversion precipitation method and direct precipitation method. Four kinds of photocatalysts are donated as Ag3PO4-GX, Ag3PO4-SR, Ag3PO4-ZJ and Ag3PO4-ZH, respectively. The obtained materials were characterized by XRD, UV-VIS DRS, SEM and BET.XRD analyse results showed that the Ag3PO4 prepared by four methods have good crystallinity form sharp diffraction peak. UV-VIS DRS results showed that the band gap of four samples are 1.66 eV (Ag3PO4-GX), 1.91eV (Ag3PO4-ZJ), 2.13 eV (Ag3PO4-ZH) and 3.37 eV (Ag3PO4-SR), respectively. SEM results showed that the samples prepared by direct precipitation method and hydrothermal method make Ag3PO4 particles more uniform and the samples have better morphology, more porous and uniform distribution of particles. The surface area of the samples prepared by the four methods is in the range of 20-35 m2/g. The photocatalytic capacity of four Ag3PO4 were investigates by methyl orange, methyl blue and ofloxacin. The photodegradation experiment showed that the Ag3PO4 photocatalyst prepared by direct precipitation method exhibited best degradation efficiency under the visible light irradiation. The mechanism of the remarkable photocatalysis was also explored by determining the role of active radicals. The results showed that h+ was the main active oxidation species in the presence of aerobic degradation of levofloxacin, while ⋅OH active species had little effect on the degradation of pollutants.