Synthesis of silver nanoparticles deposited on silica by
                    <i>γ</i>
                    -irradiation and preparation of PE/Ag nano compound masterbatches

Dang

Adv. Nat. Sci: Nanosci. Nanotechnol.

et al. 2014

Self Cite

Porous ceramic candle filters (PCCF) were prepared by sintering silica from rice husk with silver nanoparticles (AgNPs)/zeolite A at about 1050 °C to create bactericidal PCCF/AgNPs for water disinfection. The silver content in PCCF/AgNPs was of 300-350 mg kg −1 determined by inductively coupled plasma-atomic emission spectroscopy (ICP-AES) and the average pore size of PCCF/AgNPs was of 50-70 Å measured by Brunauer-Emmett-Teller (BET) method. The bactericidal activity and silver release of PCCF/AgNPs have been investigated by flow test with water flow rate of 5 L h −1 and initial inoculation of E. coli in inlet water of 10 6 CFU/100 mL. The volume of filtrated water was collected up to 500 L. Results showed that the contamination of E. coli in filtrated water was <1 CFU/100 mL and the content of silver released from PCCF/AgNPs into filtrated water was <1 μg L −1 , it is low, far under the WHO guideline of 100 μg L −1 at maximum for drinking water. Based on the content of silver in PCCF/AgNPs and in filtrated water, it was estimated that one PCCF/AgNPs could be used to filtrate of ∼100 m 3 water. Thus, as-prepared PCCF/AgNPs releases low content of silver into water and shows effectively bactericidal activity that is promising to apply as point-of-use water treatment technology for drinking water disinfection.

Section: Characteristics Of Agnps/zeolitementioning

confidence: 57%

Bactericidal activity and silver release of porous ceramic candle filter prepared by sintering silica with silver nanoparticles/zeolite for water disinfection

Dang

Adv. Nat. Sci: Nanosci. Nanotechnol.

et al. 2014

Self Cite

“…The amount of Ag needs to be controlled to get the optimal number of active sites and an even distribution of Ag is needed so that the Ag/SiO 2 composites have consistent performance. Many attempts have been devoted to realising it, including spray [48], deposition [49][50], sol-gel [51][52][53], impregnation [54], coating [55], and irradiation methods [56].…”

Section: Introductionmentioning

confidence: 99%

Structure and Properties of Silver-Silica Composite Prepared From Rice Husk Silica and Silver Nitrate

Sembiring¹

2022

Ceramics - Silikaty

This research characterises the structure and physical properties of silver/silica (Ag/SiO 2 ) composites using silver nitrate (AgNO 3 ) and rice husk silica sols as precursors. The Ag/SiO 2 composites were produced with different AgNO 3 concentrations (0.3-0.8 M) heated to a temperature of 850 °C. All the composites were fully characterised in the solid state via various techniques; Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Scanning Electron Microcopy/ Energy Dispersive Spectroscopy (SEM/EDS), Thermal Gravimetry Analysis/Differential Thermal Analysis (TGA/DTA) were used to investigate the effects of changes in the sol concentration on the crystalline of Ag/SiO 2 composites. In addition, a Particle Size Analysis (PSA) and a UV-visible technique were used to measure the particle size distribution and band gap energy, respectively. The X-ray diffraction (XRD) showed cristobalite and Ag face-centre-cubic (fcc) structures, indicating the deposition of the Ag particles on the SiO 2 surfaces. The particle size distributions were found to be in a range of 0.01-0.42 µm and 0.49-3.43 µm, followed the band gap energies in a range of 1.97 to 2.17 eV, and 3.63 to 3.57 eV. As a result, the Ag/SiO 2 composite promises to be a great biomedical material degrading high antibacterial properties.

“…Gamma irradiation induces ionization and excitation of the water molecules, generating radiolytic molecular and radical species such as solvated electrons, hydroxyl radicals, and hydrogen atoms. The solvated electrons and hydrogen atoms reduce the metal ions to metal atoms, which coalesce to form more nanoparticles [ 52 ].…”

Section: Resultsmentioning

confidence: 99%

Silver-titanium polymeric nanocomposite non ecotoxic with bactericide activity

2022

Graphical Abstract In view of the intense interest in applications of silver nanoparticles in products for the medical field and in food preservation packaging due to their antimicrobial properties, the ecotoxicology of silver nanocomposites was evaluated in films. Test with the sea urchin Echinometra lucunter , to evaluate embryonic development and contamination by the action of silver and titanium nanoparticles in polyethylene nanocomposite films presents new results. The silver nanoparticle’s stability in polymeric materials can be enhanced by adding carriers, such as titanium dioxide and montmorillonite clay (MMT) without to producing one unfriendly material. For this research, low-density polyethylene (LDPE)/linear low-density polyethylene (LLDPE) were used processed in a twin-screw extruder, followed by gamma irradiation with 25 kGy and characterized by ecotoxicology assays, field emission scanning electron microscopy (FESEM), scanning electron microscopy and energy dispersive spectroscopy (SEM–EDX), differential scanning calorimetry (DSC), thermogravimetric analysis (TG), Raman spectroscopy (SERS) and mechanical properties. The antibacterial properties of the LDPE films were investigated against Escherichia coli and Staphylococcus aureus . The gamma irradiation had an important effect in the synthesis of silver nanoparticles resulting in bactericidal activity and the death of 100% of the tested bacteria. The evaluation of the environment was considered with the ecotoxicological investigation carried out. The results indicated that the polymeric films with silver nanoparticles and TiO 2 do not contaminate the environment and neither interfere with the larval development of Echinometra lucunter . The obtained materials can be used in various applications with antimicrobial properties.