In situ Polymerization of Polyaniline/Samarium Oxide - Anatase Titanium Dioxide (PANI/Sm2O3-TiO2) Nanocomposite: Structure, Thermal and Dielectric Constant Supercapacitor Application Study

The effect of plasticizer on dielectric properties of poly(methyl methacrylate) (PMMA)/titanium dioxide (TiO2) composites was investigated. Propylene carbonate (PC) was used as plasticizer in the samples which were prepared with the conventional solvent casting technique. Scanning Electron Microscopy with Energy Dispersive X-Ray Analysis (SEM-EDX) and Differential scanning calorimetry (DSC) analyses and LCR Meter measurements (performed between 300 K and 400 K), were conducted to examine the properties of the composites. With the addition of plasticizer, the thermal properties have changed and the dielectric constant of the composite has increased significantly. The glass transition temperature of pure PMMA measured 121.7°C and this value did not change significantly with the addition of TiO2, however, 112°C was measured in the sample with the addition 4 ml of PC. While the dielectric constant of pure PMMA was 3.64, the ε′ value increased to 5.66 with the addition of TiO2 and reached 12.6 with the addition of 4 ml PC. These changes have been attributed to increase in amorphous ratio that facilitates polymer dipolar and segmental mobility.

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Electrophoretic Deposition of CdSe Nanocrystals for Photovoltaic Applications

MRS Proceedings ◽

10.1557/proc-1031-h13-25 ◽

2007 ◽

Vol 1031 ◽

Author(s):

Nathanael Smith ◽

Kevin J Emmett ◽

Sandra J Rosenthal

Keyword(s):

Titanium Dioxide ◽

Electrophoretic Deposition ◽

Room Temperature ◽

Tio2 Thin Film ◽

Cdse Nanocrystals ◽

Photovoltaic Devices ◽

Photovoltaic Applications ◽

Nanocrystalline Titanium ◽

Alternative Techniques

AbstractCdSe nanocrystals chemically linked to nanocrystalline titanium dioxide substrates form a promising material for nanostructured photovoltaic devices. The usual method for attaching the nanocrystals to the titanium dioxide substrate is by means of a linking molecule (such as mercaptopropionic acid) or in-situ growth. In this paper, we report the use of an alternative technique, electrophoretic deposition (EPD), to directly deposit already formed CdSe nanocrystals onto the substrate. In EPD, a voltage is established between two electrodes that are immersed in a solution of nanocrystals. At room temperature, a fraction of the nanocrystals are thermally charged, and these charged nanocrystals migrate to the electrodes and adhere to the surface. A significant advantage of EPD over the use of linking molecules is the speed with which the nanocrystals are deposited: EPD takes only a few minutes, compared to the several hours required for the alternative techniques. Additionally, we have fabricated initial photovoltaic devices based on electrophoretically deposited CdSe nanocrystals on a planar TiO2 thin film.

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Synthesis and supercapacitor performance of polyaniline-titanium dioxide-samarium oxide (PANI/TiO2-Sm2O3) nanocomposite

Chemical Papers ◽

10.1007/s11696-021-01948-6 ◽

2021 ◽

Author(s):

Zaid H. Mahmoud ◽

Reem Adham AL-Bayati ◽

Anees A. Khadom

Keyword(s):

Titanium Dioxide ◽

Samarium Oxide ◽

Supercapacitor Performance

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Investigation of the photodecomposition process of thin layers of arachidic acid on titanium dioxide coatings modified by silver nanoparticles observed in situ by atomic force microscopy

Journal of Photochemistry and Photobiology A Chemistry ◽

10.1016/j.jphotochem.2016.12.009 ◽

2017 ◽

Vol 335 ◽

pp. 239-247 ◽

Cited By ~ 3

Author(s):

Karolina Bałuszyńska ◽

Aneta Kisielewska ◽

Kaja Spilarewicz-Stanek ◽

Joanna Ginter ◽

Ireneusz Piwoński

Keyword(s):

Atomic Force Microscopy ◽

Silver Nanoparticles ◽

Titanium Dioxide ◽

Arachidic Acid ◽

Thin Layers ◽

Force Microscopy ◽

Atomic Force

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Stress Development in Low Dielectric Constant Silica Films During Drying and Heating Process

MRS Proceedings ◽

10.1557/proc-594-463 ◽

1999 ◽

Vol 594 ◽

Cited By ~ 1

Author(s):

Mengcheng Lu ◽

C. Jeffrey Brinker

Keyword(s):

Dielectric Constant ◽

Tensile Stress ◽

Sol Gel ◽

Low Dielectric Constant ◽

Heating Process ◽

Residual Tensile Stress ◽

Silica Films ◽

Stress Development ◽

Low Dielectric

AbstractLow dielectric constant silica films are made using a surfactant templated sol-gel process (K∼2.5) or an ambient temperature and pressure aerogel process (K∼1.5). This paper will present the in-situ measurement and analysis of stress development during the making of these films, from the onset of drying till the end of heating. The drying stress is measured by a cantilever beam technique; the thermal stress is measured by monitoring the wafer curvature using a laser deflection method. During the course of drying, the surfactant templated films experience a low drying stress due to the influence of the surfactant on surface tension and extent of siloxane condensation. The aerogel films first develop a biaxial tensile stress due to solidification and initial drying. At the final stage of drying where the drying stress vanishes, dilation of the film recreates the porosity of the wet gel state, reducing the residual stress to zero. For the surfactant templated films, very small residual tensile stress remains after the heat treatment is finished (∼30MPa). Aerogel film has almost no measurable stress developed in the calcination process. In situ spectroscopic ellipsometry analysis during drying and heating, and TGA/DTA are all used to help understand the stress development.

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Enhanced Antibacterial Activity of Silver Doped Titanium Dioxide-Chitosan Composites under Visible Light

Materials ◽

10.3390/ma11081403 ◽

2018 ◽

Vol 11 (8) ◽

pp. 1403 ◽

Cited By ~ 9

Author(s):

Jie Li ◽

Bing Xie ◽

Kai Xia ◽

Yingchun Li ◽

Jing Han ◽

...

Keyword(s):

Particle Size ◽

Antibacterial Activity ◽

Titanium Dioxide ◽

Visible Light ◽

Silver Ions ◽

Antibacterial Activities ◽

Nano Tio2 ◽

Inverse Emulsion ◽

Potential Applications

Nano titanium dioxide (TiO2) with photocatalytic activity was firstly modified by diethanolamine, and it was then doped with broad spectrum antibacterial silver (Ag) by in situ method. Further, both Ag doped TiO2-chitosan (STC) and TiO2-chitosan (TC) composites were prepared by the inverse emulsion cross-linking reaction. The antibacterial activities of STC composites were studied and their antibacterial mechanisms under visible light were investigated. The results show that in situ doping and inverse emulsion method led to good dispersion of Ag and TiO2 nanoparticles on the cross-linked chitosan microsphere. The STC with regular particle size of 1–10 μm exhibited excellent antibacterial activity against E. coli, P. aeruginosa and S. aureus under visible light. It is believed that STC with particle size of 1–10 μm has large specific surface area to contact with bacterial cell wall. The increased antibacterial activity was attributed to the enhancement of both electron-hole separations at the surface of nano-TiO2 by the silver ions under the visible light, and the synergetic and sustained release of strong oxidizing hydroxyl radicals of nano-TiO2, together with silver ions against bacteria. Thus, STC composites have great potential applications as antibacterial agents in the water treatment field.

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