The present study describes the anodic growth of TiO2 nanotube thin layer on stainless steel 304 in ethylene glycol/water/ammonium fluoride electrolyte. In this regard, pure titanium was coated on stainless steel 304 substrates by a... more
The present study describes the anodic growth of TiO2 nanotube thin layer on stainless steel 304 in ethylene glycol/water/ammonium fluoride electrolyte. In this regard, pure titanium was coated on stainless steel 304 substrates by a physical vapor deposition magnetron sputtering (PVDMS) technique. The adhesion strength of the coating to the substrate was investigated. TiO2 nanotubes were generated on the top of the Ti coated substrates by means of anodization technique at a 25 V potential and times of 20, 40, and 60 min in an ammonium fluoride electrolyte solution. The anodized Ti-coated samples were heat-treated at 280 1C, 430 1C and 620 1 Ci n aN 2 gas furnace to attain diverse phases. The mechanical properties of TiO2 nanotube arrays coated substrate were explored by a nanoindentation apparatus. The results illustrate that the Young's modulus and surface hardness of TiO2 nanotube-coated substrates are increased with increasing annealing temperatures (280 1C, 430 1C and 620 1C...
In this research we report the gas-sensing properties of TiO2-x/TiO2-based hetero-structure, which was ‘self-heated’ by current that at constant potential passed through the structure. Amperometric measurements were applied for the... more
In this research we report the gas-sensing properties of TiO2-x/TiO2-based hetero-structure, which was ‘self-heated’ by current that at constant potential passed through the structure. Amperometric measurements were applied for the evaluation of sensor response towards ethanol, methanol, n-propanol and acetone gases/vapours. The sensitivity towards these gases was based on electrical resistance changes, which were determined by amperometric measurements of current at fixed voltage applied between Pt-based contacts/electrodes deposited on the TiO2-x/TiO2-based layer. X-ray diffraction (XRD) analysis revealed the formation of TiO2-x/TiO2-based hetero-structure, which is mainly based on Ti3O5/TiO2 formed during the hydro-thermal oxidation-based sensing-layer preparation process. Additionally, photoluminescence and time-resolved photoluminescence decay kinetics-based signals of this sensing structure revealed the presence of TiO2 mainly in the anatase phase in the TiO2-x/TiO2-based hete...
In this paper, a basic electro-analytical study on the behavior of anatase TiO 2 in aqueous NaOH has been presented using cyclic voltammetry technique (CV). The study has explored the possibility of using TiO 2 as anode material for ARSBs... more
In this paper, a basic electro-analytical study on the behavior of anatase TiO 2 in aqueous NaOH has been presented using cyclic voltammetry technique (CV). The study has explored the possibility of using TiO 2 as anode material for ARSBs in presence of 5 M NaOH aqueous electrolyte. CV profiles show that anatase TiO 2 exhibits reversible sodium ion insertion/de-insertion reactions. CV studies of TiO 2 anode in aqueous sodium electrolytes at different scan rate shows that the Na + ion insertion reaction at the electrode is diffusion controlled with a resistive behavior. Proton insertion from aqueous sodium electrolytes into TiO 2 cannot be ruled out. To confirm the ion inserted and de-inserted, CV studies are done at different concentration of NaOH and it is found that at lower concentrations of NaOH, proton insertion process competes with Na + ion insertion process and as the concentration increases, the Na + ion insertion process becomes the predominant electrode reaction making it suitable anode materials for aqueous sodium batteries in 5 M NaOH.
ABSTRACT Using an organometallic precursor, TiO2 coatings were fabricated on surfaces of quartz, zircon and rutile sands. X ray Diffraction, X ray Fluorescence, UV Vis spectroscopy and surface area measurement were used to characterise... more
ABSTRACT Using an organometallic precursor, TiO2 coatings were fabricated on surfaces of quartz, zircon and rutile sands. X ray Diffraction, X ray Fluorescence, UV Vis spectroscopy and surface area measurement were used to characterise support materials. The phase composition and morphology of the coatings were characterised by laser Raman spectroscopy and SEM respectively. A packed bed reactor was used to study the inactivation of Escherichia coli in recirculating water by the supported photocatalysts. It was found that the sand grains were well coated with a homogenous layer of TiO2 and coatings were well adhered, exhibiting a mixed anatase rutile composition after firing at 850C. Photocatalytic activity was highest in coatings applied to quartz sand, although sterilisation of the recirculating water was not achieved with any of the materials investigated. The advantages of quartz as a TiO2 photocatalyst support material are likely a result of this materials higher purity and optical transmittance. Potential enhancement through Si doping cannot be ruled out.
The use of nanotechnology in conservation is a relatively new concept. Usually, classical cleanup methods take into account the use of other chemicals: On the one hand they help the environment destroying pollutants, but on the other hand... more
The use of nanotechnology in conservation is a relatively new concept. Usually, classical cleanup methods take into account the use of other chemicals: On the one hand they help the environment destroying pollutants, but on the other hand they often become new pollutants. Among the new oxidation methods called advanced oxidation processes, heterogeneous photocatalysis has appeared an emerging technology with several economic and environmental advantages. A new sol–gel method of synthesis of TiO 2 anatase is reported in this work using lithium and cobalt (II) salts. The activation energy of the doped photocatalyst was analyzed by solid-state UV–Vis spectrophotometer. The mobility of Li ions on TiO 2 NPs surface was studied by 7 Li MAS NMR spectroscopy. Use of doped nanotitania is suggested from authors for the removal of pollutants in confined areas containing goods that must be preserved from decomposition and aging phenomena.
In this work, the preparation of nano-sized TiO2 powder via sol-gel precipitation route by using hydrolysis of titanium tetraisopropoxide (Ti(OiPr)4) with ethanol and water mixture as titania source. The samples were characterized by... more
In this work, the preparation of nano-sized TiO2
powder via sol-gel precipitation route by using hydrolysis of
titanium tetraisopropoxide (Ti(OiPr)4) with ethanol and
water mixture as titania source. The samples were
characterized by XRD, SEM-EDAX, and FT-IR studies.
Surface morphological studies obtained from SEM
micrograph showed the particles with the spherical shapes are
anatase in nature. The Crystalline size of TiO2 powder has
obtained is ~6nm for anatase at 400 ºC by controlling the
acidity. In FT-IR, all the peaks observed were around 460-560
cm-1 due to stretching and bending vibrations of -OH groups
