Rapid breakdown anodization (RBA) process was used to fabricate TiO2 sensor to measure pressure and humidity and sense gases at room temperature. This chemical process transformed Ti to its oxide (TiO2) as a powder with amorphous phase as X ray diffraction (XRD) technique confirmed.  This oxide consisted from semi spherical nanoparticles and titania nanotubes (TNTs) as Scanning electron microscope (SEM) technique showed.  TiO2 powder was deposited on Ti substrates by using electrophoretic deposition (EPD) method.   Average pressure sensitivity was 0.34 MΩ/bar and hysteresis area was 1.4 MΩ .bar. Resistance of TiO2 decreased exponentially with the increasing of relative humidity (RH%). The sensitivity% of TiO2 for RH% was greater than 70% in the range of (50-95). TiO2 was tested as a sensor for Ammonia, Ethanol and Methanol. Its sensitivity and selectivity towards Ammonia were the greatest but the shortest response and recovery times were recorded toward Methanol.

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The deposition of metal oxides powder faces several problems, including poor adhesion to the bases deposited on them, the presence of many cracks, poor thickness control, and other disadvantages. The current study gives a new and simple idea to deposit thin films using two ZnO powders with nano and microparticle sizes on glass substrates. This was done by transforming the powders to Zinc acetate and then using chemical spray pyrolysis to deposit ZnO thin films. Scanning electron microscope (SEM) images showed that the prepared film from the nanopowder (ZnONano) lost the independence of powder’s nanoparticles and became a homogeneous film with nano projections. But the deposited one from the micro powder (ZnOMicro) had both nanorods and nanoplates. The different shapes and sizes of ZnO particles in ZnOMicro powder were disappeared after the Spray process. The two deposited films were homogeneous, crack-free and there were controllable thicknesses during the deposition. X-ray spectroscopy (EDS) was used to measure weights and atomic percentages of elements for the deposited films. The structures of the deposited films were approximately identical as the X-ray diffraction (XRD) technique showed. The optical properties of these two films were studied and their parameters were measured and calculated.

An anodizing method was used to produce TiO2 nanotubes (TNTs) on Ti metal bases. These tubes were transformed into lobed nanotubes (LNTs) by heating at 6000C as scanning electron microscopy (SEM) images showed. A rapid break down anodizing (RBA) technique was utilized to produce TiO2 nanoparticles (TNPs). These particles were deposited on LNTs by the electrophoretic deposition (EPD) method. An X-ray diffraction (XRD) test revealed the polycrystalline composition of the formed LNTs and the amorphous structure of TNPs. The bioactivity of LNTs and the deposited TNPs on the LNTs were tested by immersing them in simulated body fluid (SBF) for one month. For the two samples, XRD patterns showed the appearance of small peaks of hydroxyapatite (HAp), which indicates the bioactivity of these samples. SEM images show that the HAp layer on LNTs was in the form of protrusions, while on TNPs it was in the form of crossed filaments.

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