Green Synthesis of Silver Nanoparticles by Tannic Acid with Improved Catalytic Performance Towards the Reduction of Methylene Blue

NANO ◽  
2018 ◽  
Vol 13 (01) ◽  
pp. 1850003 ◽  
Author(s):  
Yueyue Hao ◽  
Nan Zhang ◽  
Jing Luo ◽  
Xiaoya Liu
Keyword(s):  
Methylene Blue ◽  
Particle Size ◽  
Silver Nanoparticles ◽  
Catalytic Activity ◽  
Tannic Acid ◽  
Molar Ratio ◽  
High Catalytic Activity ◽  
Ag Nps ◽  
Environmental Friendly ◽  
Vis Spectroscopy

In this work, a facile, environmental-friendly and cost-effective method was developed to prepare silver nanoparticles (Ag NPs) in aqueous solution at room temperature. In our approach, tannic acid was employed as the reducing agent and stabilizer simultaneously, avoiding the usage of any toxic agent. The tannic acid derived silver nanoparticles (TA-Ag NPs) were fully characterized by UV-Vis spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and thermogravimetric analyzer (TGA). The particle size of the synthesized TA-Ag NPs is tunable from 6.5[Formula: see text]nm to 19.2[Formula: see text]nm with narrow distribution by varying the molar ratio of TA to silver precursor. Efficient reduction of methylene blue (MB) catalyzed by TA-Ag NPs was observed, which was dependent upon the particle size of TA-Ag NPs or the TA concentration used for synthesis. By optimizing the TA concentration, complete reduction of MB was accomplished by TA-Ag NPs within 8[Formula: see text]min. The high catalytic activity of TA-Ag NPs was attributed to their nanosize and good dispersity as well as the electrostatic interaction between TA and MB which induces rapid enrichment of MB towards TA-Ag NPs, creating a locally concentrated layer of MB. Considering the facile and environmental-friendly preparation procedure and excellent catalytic activity, TA-Ag NPs are green, efficient and highly economical candidates for the catalysis of organic dyes and extendable of other reducible contaminants as well.

On the Influence of Silver Nanoparticles Size in the Electrical Conductivity of PEDOT: PSS

2010 ◽  
Vol 644 ◽  
pp. 85-90 ◽  
Author(s):  
Rebeca G. Melendez ◽  
Karla J. Moreno ◽  
Ivana Moggio ◽  
Eduardo Arias ◽  
Arturo Ponce ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Particle Size ◽  
Silver Nanoparticles ◽  
Reducing Agent ◽  
Molar Ratio ◽  
Plasmon Band ◽  
Vis Spectroscopy

In this paper, we studied the influence of the silver nanoparticles size on the electrical conductivity of PEDOT:PSS in Ag(PEDOT:PSS) films. The silver nanoparticles were synthesized in presence of PEDOT:PSS by varying the molar ratio between AgNO3 and the reducing agent (NaBH4). Both the particle size determined by TEM and the plasmon band obtained by UV-Vis spectroscopy were found to be strongly dependent on the reducing agent concentration. The electrical conductivity increases inversely with the concentration of reducing agent from 5.24 x 10-4 up to 1.63 S/cm; three orders of magnitude higher than pristine PEDOT:PSS.

scholarly journals Photo-induced chemical reduction of silver bromide to silver nanoparticles

2011 ◽  
Vol 9 (6) ◽  
pp. 982-989 ◽  
Author(s):  
Agnieszka Król-Gracz ◽  
Ewa Michalak ◽  
Piotr Nowak ◽  
Agnieszka Dyonizy
Keyword(s):  
Silver Nanoparticles ◽  
Chemical Reduction ◽  
Silver Bromide ◽  
Molar Ratio ◽  
Efficient Production ◽  
Ag Nps ◽  
Transmission Electron ◽  
Vis Spectroscopy ◽  
Nanoparticle Suspensions ◽  
Actinic Radiation

AbstractThis paper discusses the experimental results of the production of nanocolloidal silver using photoreduction method. Ultrafine crystalline gelatine-stabilised aqueous suspensions of silver bromide were used as a substrate for the synthesis of silver nanoparticles (Ag NPs). The influences of the reductant to substrate molar ratio, the medium’s pH, the type of the source of actinic radiation and the time of exposure to the efficient production of the Ag NPs were studied. A typical reaction was suggested, which involves the photo-induced reduction of silver bromide nanocrystals in the presence of ascorbic acid under specified physicochemical conditions. The properties of resultant silver particles were examined using UV-Vis spectroscopy and Dynamic Light Scattering (DLS). In addition, Transmission Electron Microscopy (TEM) was used for imaging the silver nanoparticle suspensions.

Controlled synthesis of monodisperse silver nanoparticles supported layered double hydroxide catalyst

RSC Advances ◽  
2015 ◽  
Vol 5 (17) ◽  
pp. 13239-13245 ◽  
Author(s):  
D. A. Islam ◽  
D. Borah ◽  
H. Acharya
Keyword(s):  
Silver Nanoparticles ◽  
Catalytic Activity ◽  
Layered Double Hydroxide ◽  
Layered Double Hydroxides ◽  
Alcohol Oxidation ◽  
High Catalytic Activity ◽  
Controlled Synthesis ◽  
Ag Nps ◽  
Double Hydroxide ◽  
Double Hydroxides

Monodisperse silver nanoparticles supported layered double hydroxides (Ag NPs–LDH) were preferentially deposited on the outer surfaces of pillared LDH offered a high catalytic activity on alcohol oxidation.

A novel silver nanoparticle embedded mesoporous polyaniline (mPANI/Ag) nanocomposite as a recyclable catalyst in the acylation of amines and alcohols under solvent free conditions

RSC Advances ◽  
2014 ◽  
Vol 4 (80) ◽  
pp. 42670-42681 ◽  
Author(s):  
Usha Mandi ◽  
Anupam Singha Roy ◽  
Biplab Banerjee ◽  
Sk. Manirul Islam
Keyword(s):  
Silver Nanoparticles ◽  
Acetic Acid ◽  
Catalytic Activity ◽  
Silver Nanoparticle ◽  
Solvent Free ◽  
Organic Polymer ◽  
High Catalytic Activity ◽  
Ag Nps ◽  
Solvent Free Conditions ◽  
Highly Dispersed

Highly dispersed silver nanoparticles (Ag NPs) have been embedded into a mesoporous organic polymer (mPANI) and the material showed high catalytic activity in the acylation of amines and alcohols using acetic acid.

Simple Way for Ag-NPs Preparation based on Starch Macromolecule

2021 ◽  
Vol 18 ◽  
Author(s):  
H.M. Fahmy ◽  
A.A. Ali ◽  
A. Abou-Okeil
Keyword(s):  
Particle Size ◽  
Antibacterial Properties ◽  
Particle Size Analysis ◽  
Molar Ratio ◽  
Size Analysis ◽  
Ag Nps ◽  
Stabilizing Agent ◽  
Oxidized Starch ◽  
Vis Spectroscopy ◽  
The Mean

: Finding a sustainable, inexpensive way for Ag-NPs synthesis is considered as one of the most important requirements for industrial application. Oxidized starch was prepared using sodium periodate. Oxidized starch (DAS) was characterized by measuring aldehyde content and using FTIR spectroscopy. DAS was used as reducing and stabilizing agent for the preparation of Ag nanoparticles (Ag-NPs). Factors that may affect the preparation of Ag-NPs include pH, AgNO3/DAS molar ratio, temperature and time were studied. UV-Vis. spectroscopy and particle size analysis showed that DAS can act as reducing and stabilizing agent for the preparation of Ag-NPs and the mean particle size was 19 nm. The so prepared AgNPs were used as antibacterial agent for cotton fabric using the pad dry cure method. The results of antibacterial test showed that the presence of Ag-NPs enhanced the antibacterial properties of the treated cotton fabrics.

Comparative Photocatalytic Degradation of Organic Dyes Using Silver Nanoparticles Synthesized from Padina tetrastromatica

2017 ◽  
Vol 14 (1) ◽  
pp. 71-75
Author(s):  
Clara Gnana Selvi Barnabas ◽  
Jayaraman Theerthagiri ◽  
Amutha Santhanam
Keyword(s):  
Methylene Blue ◽  
Silver Nanoparticles ◽  
Catalytic Activity ◽  
Acridine Orange ◽  
Metallic Nanoparticles ◽  
Dye Degradation ◽  
Time Interval ◽  
Active Components ◽  
Ag Nps ◽  
Padina Tetrastromatica

Background: Seaweeds, being abundant sources of active components have attained much interest in recent times. The seaweeds are routinely used in life science research and are well known for their biological applications. In addition to that, the synthesis of metallic nanoparticles from these natural resources has its own attraction in drug delivery and was observed by using 2 mL of Ag NP colloids. Objective: In this study, the synthesis of silver nanoparticles (Ag NPs) using Padina tetrastromatica has been evaluated for their catalytic activity in the degradation of organic dye. Method: The catalytic activity of the biosynthesized Ag NP colloid was studied for the degradation of Methylene blue (MB) and Acridine orange (AO) dye. The degradation of methylene blue and acridine orange was observed at regular time interval by using UV-vis absorption spectra at 664 nm and 490 nm respectively. Results: The percentage of dye degradation increased in the presence of NaBH4. It was observed that 80.09% of MB dye reduction was observed by using 2 mL of Ag NP colloids. The acridine orange dye showed reduction of 83.06%. The rate constants for the reduction of Methylene blue (MB) and acridine orange (AO) dye using 2 mL Ag NPs colloids are 0.077 and 0.090 min-1, respectively.

Green Synthesis of Silver Nanoparticles with Exceptional Colloidal Stability and its Catalytic Activity Toward Nitrophenol Reduction

NANO ◽  
2016 ◽  
Vol 11 (04) ◽  
pp. 1650046 ◽  
Author(s):  
Manisha Sharma ◽  
Amit Mishra ◽  
Vinod Kumar ◽  
Soumen Basu
Keyword(s):  
Silver Nanoparticles ◽  
Catalytic Activity ◽  
Colloidal Stability ◽  
Ag Nps ◽  
Step Process ◽  
Synthesis Parameters ◽  
Salt Addition ◽  
Nitrophenol Reduction ◽  
Vis Spectroscopy ◽  
One Step

Silver nanoparticles (Ag NPs) were synthesized by one-step process in the presence of kollicoat as capping, reducing and stabilizing mediator. The synthesized NPs were characterized by using FTIR, TEM, DLS, XRD, EDS and UV-Vis spectroscopy. The resulting Ag NPs had an incomparable colloidal stability against the salt addition and change of pH. The effect of different synthesis parameters and the catalytic property of the NPs were examined.

scholarly journals Single-Step Green Synthesis of Highly Concentrated and Stable Colloidal Dispersion of Core-Shell Silver Nanoparticles and Their Antimicrobial and Ultra-High Catalytic Properties

Nanomaterials ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 1007
Author(s):  
Azam Ali ◽  
Mariyam Sattar ◽  
Fiaz Hussain ◽  
Muhammad Humble Khalid Tareen ◽  
Jiri Militky ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Green Synthesis ◽  
Tannic Acid ◽  
Rate Constant ◽  
Catalytic Properties ◽  
Colloidal Dispersion ◽  
Alkaline Condition ◽  
Core Shell ◽  
Average Particle ◽  
Ag Nps

The versatile one-pot green synthesis of a highly concentrated and stable colloidal dispersion of silver nanoparticles (Ag NPs) was carried out using the self-assembled tannic acid without using any other hazardous chemicals. Tannic acid (Plant-based polyphenol) was used as a reducing and stabilizing agent for silver nitrate in a mild alkaline condition. The synthesized Ag NPs were characterized for their concentration, capping, size distribution, and shape. The experimental results confirmed the successful synthesis of nearly spherical and highly concentrated (2281 ppm) Ag NPs, capped with poly-tannic acid (Ag NPs-PTA). The average particle size of Ag NPs-PTA was found to be 9.90 ± 1.60 nm. The colloidal dispersion of synthesized nanoparticles was observed to be stable for more than 15 months in the ambient environment (25 °C, 65% relative humidity). The synthesized AgNPs-PTA showed an effective antimicrobial activity against Staphylococcus Aureus (ZOI 3.0 mM) and Escherichia coli (ZOI 3.5 mM). Ag NPs-PTA also exhibited enhanced catalytic properties. It reduces 4-nitrophenol into 4-aminophenol in the presence of NaBH4 with a normalized rate constant (Knor = K/m) of 615.04 mL·s−1·mg−1. For comparison, bare Ag NPs show catalytic activity with a normalized rate constant of 139.78 mL·s−1·mg−1. Furthermore, AgNPs-PTA were stable for more than 15 months under ambient conditions. The ultra-high catalytic and good antimicrobial properties can be attributed to the fine size and good aqueous stability of Ag NPs-PTA. The unique core-shell structure and ease of synthesis render the synthesized nanoparticles superior to others, with potential for large-scale applications, especially in the field of catalysis and medical.

scholarly journals Green synthesis of silver nanoparticles: Characterization and its potential biomedical applications

2021 ◽  
Vol 10 (1) ◽  
pp. 412-420
Author(s):  
Mona S. Alwhibi ◽  
Dina A. Soliman ◽  
Manal A. Awad ◽  
Asma B. Alangery ◽  
Horiah Al Dehaish ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Aloe Vera ◽  
Inhibition Zone ◽  
Biologically Active ◽  
Noble Metal Nanoparticles ◽  
Biological Synthesis ◽  
Ag Nps ◽  
Mouse Melanoma ◽  
Therapeutic Benefits ◽  
Vis Spectroscopy

Abstract In recent times, research on the synthesis of noble metal nanoparticles (NPs) has developed rapidly and attracted considerable attention. The use of plant extracts is the preferred mode for the biological synthesis of NPs due to the presence of biologically active constituents. Aloe vera is a plant endowed with therapeutic benefits especially in skincare due to its unique curative properties. The present study focused on an environmental friendly and rapid method of phytosynthesis of silver nanoparticles (Ag-NPs) using A. vera gel extract as a reductant. The synthesized Ag-NPs were characterized by transmission electron microscopy (TEM), UV-Vis spectroscopy, Fourier transform infrared (FTIR), and dynamic light scattering (DLS). TEM micrographs showed spherical-shaped synthesized Ag-NPs with a diameter of 50–100 nm. The UV-Vis spectrum displayed a broad absorption peak of surface plasmon resonance (SPR) at 450 nm. The mean size and size distribution of the formed Ag-NPs were investigated using the DLS technique. Antibacterial studies revealed zones of inhibition by Ag-NPs of A. vera (9 and 7 mm) against Pseudomonas aeruginosa and Escherichia coli, respectively. Furthermore, the antifungal activity was screened, based on the diameter of the growth inhibition zone using the synthesized Ag-NPs for different fungal strains. Anticancer activity of the synthesized Ag-NPs against the mouse melanoma F10B16 cell line revealed 100% inhibition with Ag-NPs at a concentration of 100 µg mL−1. The phytosynthesized Ag-NPs demonstrated a marked antimicrobial activity and also exhibited a potent cytotoxic effect against mouse melanoma F10B16 cells. The key findings of this study indicate that synthesized Ag-NPs exhibit profound therapeutic activity and could be potentially ideal alternatives in medicinal applications.

The Influence of Fe/Al Molar Ratio on Microreactor-Based Catalyst Preparation and Carbon Nanotube Preparation

2021 ◽  
Vol 1036 ◽  
pp. 130-136
Author(s):  
Ting Qun Tan ◽  
Lei Geng ◽  
Yan Lin ◽  
Yan He
Keyword(s):  
Carbon Nanotubes ◽  
Catalytic Activity ◽  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Small Diameter ◽  
High Specific Surface Area ◽  
Detection Methods ◽  
Molar Ratio ◽  
High Catalytic Activity

In order to prepare carbon nanotubes with high specific surface area, small diameter, low resistivity, high purity and high catalytic activity, the Fe-Mo/Al2O3 catalyst was prepared based on the microreactor. The influence of different Fe/Al molar ratios on the catalyst and the carbon nanotubes prepared was studied through BET, SEM, TEM and other detection methods. Studies have shown that the pore structure of the catalyst is dominated by slit pores at a lower Fe/Al molar ratio. The catalytic activity is the highest when the Fe/Al molar ratio is 1:1, reaching 74.1%. When the Fe/Al molar ratio is 1:2, the catalyst has a higher specific surface area, the maximum pore size is 8.63 nm, and the four-probe resistivity and ash content of the corresponding carbon nanotubes are the lowest. The higher the proportion of aluminum, the higher the specific surface area of the catalyst and the carbon nanotubes, and the finer the diameter of the carbon nanotubes, which gradually tends to relax. The results show that when the Fe/Al molar ratio is 1:2, although the catalytic activity of the catalyst is not the highest, the carbon nanotubes prepared have the best performance.

Sign in / Sign up

Export Citation Format

Share Document