scholarly journals Novel Blue-Wavelength-Blocking Contact Lens with Er3+/TiO2 NPs: Manufacture and Characterization

Nanomaterials ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 2190
Author(s):  
Lina Mohammed Shaker ◽  
Ahmed Alamiery ◽  
Mohd Takriff ◽  
Wan Nor Roslam Wan Isahak
Keyword(s):  
Energy Gap ◽  
Titanium Dioxide Nanoparticles ◽  
Anatase Phase ◽  
High Surface ◽  
High Surface Area ◽  
Visible Spectrum ◽  
Tio2 Nps ◽  
X Ray ◽  
Erbium Ions ◽  
Blue Wavelength

Thermally stable titanium dioxide nanoparticles (TiO2 NPs) doped with erbium ions (Er3+) are characterized by uniformity, low excitation energy, and high surface area. The impregnation methodology was used to enhance the optical properties of TiO2 NPs impregnated with various Er3+ ion contents. The synthesized Er3+/TiO2 samples were characterized by energy dispersive X-ray (EDX), metal mapping, UV–Visible spectrum, field emission scanning electron microscopy (FESEM), and X-ray diffraction (XRD). The Er3+ ions, per our findings, were well-distributed on the TiO2 surface of the anatase phase and there was an insignificant difference in particle size, but there was no change in the particle shapes of the Er3+/TiO2 NPs structure. The maximum band gap degradation occurred with 1.8 wt % of Er3+/TiO2, where the energy gap degraded from 3.13 to 2.63 eV for intrinsic TiO2. The synthesized Er3+/TiO2 samples possess predominantly finely dispersed erbium ion species on the surface. Er3+ ions agglomeration on the surface increased with increasing ions in each sample. We found that 0.6 wt/vol % of Er+3/TiO2 is the best optical coating and produced satisfying results in terms of blocking the transmittance of blue wavelength without reducing the image quality.

scholarly journals Efficient Photocatalytic Degradation of Organic Pollutant in Wastewater by Electrospun Functionally Modified Polyacrylonitrile Nanofibers Membrane Anchoring TiO2 Nanostructured

Membranes ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 785
Author(s):  
Fahad A. AlAbduljabbar ◽  
Sajjad Haider ◽  
Fekri Abdulraqeb Ahmed Ali ◽  
Abdulaziz A. Alghyamah ◽  
Waheed A. Almasry ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Dye Degradation ◽  
Anatase Phase ◽  
Organic Pollutant ◽  
High Surface ◽  
Hysteresis Loops ◽  
Scanning Electron Micrographs ◽  
Tio2 Nps ◽  
X Ray ◽  
Bare Tio2

In this study, polyacrylonitrile (PAN_P) nanofibers (NFs) were fabricated by electrospinning. The PAN_P NFs membrane was functionalized with diethylenetriamine to prepare a functionalized polyacrylonitrile (PAN_F) NFs membrane. TiO2 nanoparticles (NPs) synthesized in the laboratory were anchored to the surface of the PAN_F NFs membrane by electrospray to prepare a TiO2 NPs coated NFs membrane (PAN_Coa). A second TiO2/PAN_P composite membrane (PAN_Co) was prepared by embedding TiO2 NPs into the PAN_P NFs by electrospinning. The membranes were characterized by microscopic, spectroscopic and X-ray techniques. Scanning electron micrographs (SEM) revealed smooth morphologies for PAN_P and PAN_F NFs membranes and a dense cloud of TiO2 NPs on the surface of PAN_Coa NFs membrane. The attenuated total reflectance in the infrared (ATR-IR) proved the addition of the new amine functionality to the chemical structure of PAN. Transmission electron microscope images (TEM) revealed spherical TiO2 NPs with sizes between 18 and 32 nm. X-ray powder diffraction (XRD) patterns and energy dispersive X-ray spectroscopy (EDX) confirmed the existence of the anatase phase of TiO2. Surface profilometry da-ta showed increased surface roughness for the PAN_F and PAN_Coa NFs membranes. The adsorption-desorption isotherms and hysteresis loops for all NFs membranes followed the IV -isotherm and the H3 -hysteresis loop, corresponding to mesoporous and slit pores, respectively. The photocatalytic activities of PAN_Coa and PAN_Co NFs membranes against methyl orange dye degradation were evaluated and compared with those of bare TiO2 NPs.The higher photocatalytic activity of PAN_Coa membrane (92%, 20 ppm) compared to (PAN_Co) NFs membrane (41.64%, 20 ppm) and bare TiO2 (49.60%, 20 ppm) was attributed to the synergy between adsorption, lower band gap, high surface roughness and surface area.

scholarly journals Photocatalytic Degradation of Allura Red by MN-Ni Co-Doped Nanotitania under Visible Light Irradiation

2019 ◽  
Vol 8 (12) ◽  
pp. 650-657
Keyword(s):  
Electron Microscopy ◽  
Anatase Phase ◽  
High Surface ◽  
Sol Gel ◽  
High Surface Area ◽  
X Ray ◽  
Allura Red ◽  
Co Doping ◽  
Ft Ir ◽  
Co Doped

Photocatalyst has been extensive interest because of it’s new innovation to the reduce the contamination in the environment. A straight forward and economical procedure has been employed by sol-gel technique for the co-doping of Mn2+ and Ni2+ into TiO2 . The co-doped and undoped photocatalysts were described by X-ray diffraction (XRD), Scanning electron microscopy (SEM), Energy dispersive X-ray Spectroscopy (EDX), Fourier transform infrared spectroscopy (FT-IR), UV-Visible Diffused Reflectance Spectroscopy (UV Vis-DRS), Transmission electron Microscopy (TEM) and Brunauer-Emmett-Teller (BET). The portrayal results shows that anatase and rutile mixed phase was observed for some co-doped nanocatalysts and the remaining catalysts exhibits anatase phase only. It was observed by FT-IR that the shifting of frequency of Ti-O-Ti in the catalysts was seen due to substitutional doping of Mn and Ni by replace Ti and O, further the photocatalysts shows rough morphology, irregular shape of particle with size (6.5nm) and having high surface area (135.70 m2/g), less band energy (2.7 eV). The photocatalytic action of these materials was assessed by the degradation of Allura red (AR) as a contaminant. The results shows that AR has degraded within 60 minutes at doping concentrations 0.25 Wt% of Mn2+ion and 1.0 Wt% of Ni2+ ion in TiO2 (NMT2) at an optimum reaction parameters pH-4, catalyst dose 0.070g/L and at AR initial dye concentration 0.010g/L.

scholarly journals Non-Thermal Plasma-Modified Ru-Sn-Ti Catalyst for Chlorinated Volatile Organic Compound Degradation

Catalysts ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1456
Author(s):  
Yujie Fu ◽  
You Zhang ◽  
Qi Xin ◽  
Zhong Zheng ◽  
Yu Zhang ◽  
...  
Keyword(s):  
Plasma Treatment ◽  
Photoelectron Spectroscopy ◽  
High Surface ◽  
High Surface Area ◽  
Surface Oxidation ◽  
Treatment Method ◽  
X Ray ◽  
Chlorinated Volatile Organic Compounds ◽  
Volatile Organic ◽  
Doped Titania

Chlorinated volatile organic compounds (CVOCs) are vital environmental concerns due to their low biodegradability and long-term persistence. Catalytic combustion technology is one of the more commonly used technologies for the treatment of CVOCs. Catalysts with high low-temperature activity, superior selectivity of non-toxic products, and resistance to chlorine poisoning are desirable. Here we adopted a plasma treatment method to synthesize a tin-doped titania loaded with ruthenium dioxide (RuO2) catalyst, possessing enhanced activity (T90%, the temperature at which 90% of dichloromethane (DCM) is decomposed, is 262 °C) compared to the catalyst prepared by the conventional calcination method. As revealed by transmission electron microscopy, X-ray diffraction, N2 adsorption, X-ray photoelectron spectroscopy, and hydrogen temperature-programmed reduction, the high surface area of the tin-doped titania catalyst and the enhanced dispersion and surface oxidation of RuO2 induced by plasma treatment were found to be the main factors determining excellent catalytic activities.

scholarly journals Attached β-cyclodextrin/γ-(2,3-epoxypropoxy) propyl trimethoxysilane to graphene oxide and its application in copper removal

2017 ◽  
Vol 75 (10) ◽  
pp. 2403-2411 ◽  
Author(s):  
Zongxue Yu ◽  
Qi Chen ◽  
Liang Lv ◽  
Yang Pan ◽  
Guangyong Zeng ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
High Surface ◽  
High Surface Area ◽  
Esterification Reaction ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cavity Structure ◽  
Optimum Ph ◽  
Exchange Adsorption ◽  
Langmuir Isotherm Model

The environmental applications of graphene oxide and β-cyclodextrin (β-CD) have attracted great attention since their first discovery. Novel nanocomposites were successfully prepared by using an esterification reaction between β-cyclodextrin/γ-(2,3-epoxypropoxy) propyl trimethoxysilane grafted graphene oxide (β-CD/GPTMS/GO). The β-CD/GPTMS/GO nanocomposites were used to remove the Cu2+ from aqueous solutions. The characteristics of β-CD/GPTMS/GO were detected by scanning electron microscopy (SEM), Fourier transform infrared, X-ray diffraction (XRD), thermogravimetric analysis (TG) and energy dispersive X-ray (EDX). The dispersibility of graphene oxide was excellent due to the addition of β-CD. The adsorption isotherms data obtained at the optimum pH 7 were fitted by Langmuir isotherm model. The excellent adsorption properties of β-CD/GPTMS/GO for Cu2+ ions could be attributed to the apolar cavity structure of β-CD, the high surface area and abundant functional groups on the surface of GO. The adsorption patterns of β-CD/GPTMS/GO were electrostatic attraction, formation of host-guest inclusion complexes and the ion exchange adsorption. The efficient adsorption of β-CD/GPTMS/GO for Cu2+ ions suggested that these novel nanocomposites may be ideal candidates for removing other cation pollutants from waste water.

Facile Synthesis of Unique Bismuth Vanadate Nano-Knitted Hollow Cage and its Application in Environmental Remediation

2019 ◽  
Vol 74 (3) ◽  
pp. 259-263 ◽  
Author(s):  
M. Shamshi Hassan
Keyword(s):  
Environmental Remediation ◽  
Dye Degradation ◽  
High Surface ◽  
High Surface Area ◽  
Bismuth Vanadate ◽  
Bandgap Energy ◽  
Blue Dye ◽  
X Ray ◽  
Photodegradation Efficiency ◽  
Hollow Nanostructure

AbstractHierarchical bismuth vanadate (BiVO4) nano-knitted hollow cages have been synthesized by simple hydrothermal method and characterized by scanning electron microscopy, x-ray diffraction, energy-dispersive x-ray spectrometer, Fourier transform infrared, UV-Vis, and Raman. The photodegradation efficiency of BiVO4 nanocage for universally used methylene blue dye. The BiVO4 hollow nanostructure demonstrated better photocatalytic competence in dye degradation as compared to the commercial TiO2 powders (P25). The excellent dye degradation can be certified to the high crystallisation of monoclinic BiVO4 and hollow nanostructure, which leads to high surface area and small bandgap energy of 2.44 eV.

Hard-templating synthesis and enhanced photocatalysis of mesoporous titanium dioxides nanoparticles

2018 ◽  
Vol 11 (04) ◽  
pp. 1850077 ◽  
Author(s):  
K. L. Jin ◽  
X. J. Chen ◽  
J. C. Xu ◽  
Y. S. Huang ◽  
Y. B. Han ◽  
...  
Keyword(s):  
Surface Area ◽  
Anatase Phase ◽  
High Surface ◽  
High Surface Area ◽  
Mesoporous Structure ◽  
Photocatalytic Decomposition ◽  
Titanium Dioxides ◽  
Decomposition Efficiency ◽  
Templating Synthesis ◽  
Mb Adsorption

Mesoporous titanium dioxides nanoparticles (TiO2 NPs) were synthesized using activated carbon (AC) as templates after the decomposition of AC. All results indicated that TiO2 NPs with the small grain size presented the anatase phase structure. Mesoporous TiO2 NPs showed the high surface area and the surface area decreased with the TiO2 content. The removal of methylene blue (MB) indicated that the photocatalytic decomposition efficiency of mesoporous TiO2 NPs increased up to 92% for three-times doping with the TiO2 content, and then decreased. This should be attributed to the synergistic effect from the MB adsorption of mesoporous-structure and the photocatalysis of TiO2 NPs. Therefore, the higher MB concentration near TiO2 NPs from the mesoporous-structure increased the touch chance and the MB photocatalytic decomposition was promoted greatly.

scholarly journals Operando SAXS Study of a Pt/C Fuel Cell Catalyst with an X-ray Laboratory Source

2021 ◽  
Author(s):  
Johanna Schröder ◽  
Jonathan Quinson ◽  
Jacob J. K. Kirkensgaard ◽  
Matthias Arenz
Keyword(s):  
Fuel Cell ◽  
Background Subtraction ◽  
Stress Test ◽  
High Surface ◽  
High Surface Area ◽  
Carbon Support ◽  
Grazing Incidence ◽  
Saxs Data ◽  
X Ray ◽  
Fuel Cell Catalysts

Small angle X-ray scattering (SAXS) is a powerful technique to investigate the degradation of catalyst materials. Ideally such investigations are performed <i>operando</i>, i.e., during a catalytic reaction. An example of <i>operando </i>measurements is to observe the degradation of fuel cell catalysts during an accelerated stress test (AST). Fuel cell catalysts consist of Pt or Pt alloy nanoparticles (NPs) supported on a high surface area carbon. A key challenge of operando SAXS measurements is a proper background subtraction of the carbon support to extract the information of the size distribution of the Pt NPs as a function of the AST treatment. Typically, such operando studies require the use of synchrotron facilities. The background measurement can then be performed by anomalous SAXS (aSAXS) or in a grazing incidence con-figuration. In this work we present a proof-of-concept study demonstrating the use of a laboratory X-ray diffractometer for <i>operando </i>SAXS. Data acquisition of <i>operando </i>SAXS with a laboratory X-ray diffractometer is desirable due to the general challenging and limited accessibility of synchrotron facilities. They become even more crucial under the ongoing and foreseen restrictions related to the COVID-19 pandemic. Although, it is not the aim to completely replace synchrotron-based studies, it is shown that the background subtraction can be achieved by a simple experimental consideration in the setup that can ultimately facilitate <i>operando </i>SAXS measurements at a synchrotron facility. <br>

scholarly journals Organomineral nanocomposite carbon burial during Oceanic Anoxic Event 2

2014 ◽  
Vol 11 (5) ◽  
pp. 6815-6844
Author(s):  
S. C. Löhr ◽  
M. J. Kennedy
Keyword(s):  
Surface Area ◽  
High Surface ◽  
High Surface Area ◽  
Mineral Surfaces ◽  
Mineral Surface ◽  
X Ray ◽  
Oceanic Anoxic Event ◽  
Carbon Burial ◽  
Anoxic Events ◽  
Mineral Surface Area

Abstract. Organic carbon (OC) enrichment in sediments deposited during Oceanic Anoxic Events (OAEs) is commonly attributed to elevated productivity and marine anoxia. We find that OC enrichment in the late Cenomanian aged OAE2 at Demerara Rise was controlled by co-occurrence of anoxic bottom-water, sufficient productivity to saturate available mineral surfaces and variable deposition of high surface area detrital smectite clay. Redox indicators show consistently oxygen-depleted conditions, while a strong correlation between OC concentration and sediment mineral surface area (R2=0.92) occurs across a range of TOC values from 9–33%. X-ray diffraction data indicates intercalation of OC in smectite interlayers while electron, synchrotron infrared and X-ray microscopy show an intimate association between clay minerals and OC, consistent with preservation of OC as organomineral nanocomposites and aggregates rather than discrete, μm-scale pelagic detritus. Since the consistent ratio between TOC and mineral surface area suggests that excess OC relative to surface area is lost, we propose that it is the varying supply of smectite that best explains variable organic enrichment against a backdrop of continuous anoxia, which is conducive to generally high TOC during OAE2 at Demerara Rise. Smectitic clays are unique in their ability to form stable organomineral nanocomposites and aggregates that preserve organic matter, and are common weathering products of continental volcanic deposits. An increased flux of smectite coinciding with high carbon burial is consistent with evidence for widespread volcanism during OAE2, so that organomineral carbon burial may represent a potential feedback to volcanic degassing of CO2.

Aqueous colloidal sol–gel route to synthesize nanosized ceria-doped titania having high surface area and increased anatase phase stability

2007 ◽  
Vol 43 (3) ◽  
pp. 299-304 ◽  
Author(s):  
Pradeepan Periyat ◽  
K. V. Baiju ◽  
P. Mukundan ◽  
P. Krishna Pillai ◽  
K. G. K. Warrier
Keyword(s):  
Surface Area ◽  
Phase Stability ◽  
Anatase Phase ◽  
High Surface ◽  
Sol Gel ◽  
High Surface Area ◽  
Doped Titania

Influence of nanoparticles on the polymer-conditioned dewatering of wastewater sludges

2013 ◽  
Vol 67 (9) ◽  
pp. 2117-2123
Author(s):  
N. J. Boyle ◽  
G. M. Evans
Keyword(s):  
Activated Sludge ◽  
Titanium Dioxide Nanoparticles ◽  
Low Cost ◽  
High Surface ◽  
High Surface Area ◽  
Wastewater Sludge ◽  
Small Scale ◽  
Sludge Dewatering ◽  
Solids Content ◽  
The Impact

The effect of using small-scale, high surface area, nanoparticles to supplement polymer-conditioned wastewater sludge dewatering was investigated. Aerobically digested sludge and waste activated sludge sourced from the Hunter Valley, NSW, Australia, were tested with titanium dioxide nanoparticles. The sludge samples were dosed with the nanoparticles in an attempt to adsorb a component of the charged biopolymer surfactants present naturally in sludge. The sludge was conditioned with a cationic polymer. The dewatering characteristics were assessed by measuring the specific resistance to filtration through a modified time-to-filter testing apparatus. The solids content of the dosed samples was determined by a mass balance and compared to the original solids content in the activated sludge. Test results indicated that nanoparticle addition modified the structure of the sludge and provided benefits in terms of the dewatering rate. The samples dosed with nanoparticles exhibited faster water removal, indicating a more permeable filter cake and hence more permeable sludge. A concentration of 2–4% nanoparticles was required to achieve a noticeable benefit. As a comparison, the sludge samples were also tested with a larger particle size, powdered activated carbon (PAC). It was found that the PAC did provide some minor benefits to sludge dewatering but was outperformed by the nanoparticles. The solids content of the final sludge was increased by a maximum of up to 0.6%. The impact of the order sequence of particles and polymer was also investigated. It was found that nanoparticles added before polymer addition provided the best dewatering performance. This outcome was consistent with current theories and previous research through the literature. An economic analysis was undertaken to confirm the viability of the technology for implementation at a full-scale plant. It was found that, currently, this technology is unlikely to be favourable unless the nanoparticles can be sourced for a low cost.

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