38^th Global Summit on Nanoscience and Technology June 21-22, 2021 Osaka, Japan

D.K Muthee is a 27 year Old Kenyan PhD student at the University the Free State- S.A in physics department. She is a research assist at University of the free state. She published two articles during her masters and has three more under review in reputable journals.

The mixed anatase-rutile TiO2 phase compositions have attracted widespread research interest due to their superior photocatalytic activity compared to their single-phase counterparts. TiO2 properties can be improved by incorporating a dopant in the microstructures. In this observation, doping with Sn4+ ions into the lattice of TiO2 enables the phase transformation from anatase to rutile at a low temperature compared to the conventional annealing method studied in our previous work. Attention was paid to the structure, bad-gap, morphology, and photocatalytic activity of the samples. The results revealed that the Sn4+ ions entered into the TiO2 lattice by substituting the Ti4+ ions and disbursed evenly inside the matrix. The substitution triggered the lattice structure's distortion, which caused the phase transformation from anatase to rutile at a low temperature. The rutile phase increased with an increase in Sn mol %. The Sn doping leads to the bandgap's narrowing and dramatically improves the photocatalytic activity in the visible light region. Therefore, the near-contact phase junctions have been created between anatase and rutile, accounting for the effective charge separations. The mixed-phase prepared by Sn-doping shows high photoactivity in the during the oxidation of MB dye relative to the undoped TiO2. Although all Sn-TiO2 showed some degree of activity in the photocatalytic reaction, these results shows that 3.5 mol % had the highest D%. The study provides a new route for synthesizing mixed-phase TiO2 catalysts for photocatalytic applications and advances the understanding of the enhanced photocatalytic properties of anatase−rutile mixtures. Furthermore, substitutional Sn4+ doping showed significant improvement in UV photocatalysis as well as allowing for visible light activation of the catalyst.

Melaku Mekuria has completed his MSc in applied physics specializion on Laser Spectroscopy at the age of 24 years from Adama Science and Technology University school of Natural Sciences. Currently, He is working as lecturer and researcher in Hawassa university. He has also published papers.

The textile materials functionalized with nanostructures have proven to be useful for many applications, such as antimicrobial, ultraviolet (UV) light protection, and self-cleaning substrates. The objective of this research is to synthesize and characterize zinc oxide (ZnO) nanoparticles (NPs) for the applications of UV absorbers and antibacterial activities. ZnO NPs were synthesized at different temperatures and reaction media of water (S-1) and 1,2-ethanediol (S-2) using precipitation and in situ methods on the surface of cotton fabric. The average crystalline size of the ZnO NPs estimated from the Debye Scherrer formula was found to be 32 and 26 nm for S-1 and S-2, respectively. The morphology of ZnO NPs characterized by scanning electron microscope revealed that agglomerated nanostructures were homogeneously formed on the fabric surface for S-1 and S-2; on the other hand, bundle-/flower-like particles having different sizes were observed for synthesis using an in situ method. The UV protection ability of ZnO NPs coated on textiles was investigated using UV-Vis spectroscopy by measuring the UV protection factor (UPF) in the range of 280–400 nm. Higher values of UPF were obtained for ZnO NPs prepared using an in situ method. The UPF value obtained by this method was found to be 320, which demonstrates its excellent ability to block UV radiation. The antibacterial activities of ZnO NPs synthesized by the two methods possess very good bacteriostatic activity against Staphylococcus aureus and Escherichia coli bacteria demonstrated by the zone of inhibition.

Luis Ivan Serrano Corrales has obtained his master degree at the age of 26 years from Universidad de Sonora and is currently a PHD student. He has published 2 papers and has international congres participation.

Recently there have been intensive efforts in exploring innovative solar cell structures with high performance and cost effective manufacturing methods. One alternative is the use of carbon nanotubes in photoelectrochemical cells, as an effective strategy to increase the efficiency of the devices. For this purpose, in this work carbon nanotubes (CNT) we were used metal nanoparticles functionalized dioxide (TiO2) by a mechanical-thermal process, characterizing the structural, chemical and optical properties of the resulting composites. In a first step, a sintering process was applied to carbon nanotubes and at a later stage; CNTs are subjected to a mechanical process adding TiO2 nanoparticles, generating a complex nanomaterial. Characterization was carried out by Raman spectroscopy, infrared spectroscopy Fourier transform (FT-IR) spectroscopy, TEM and UV-Visible (UV-Vis). In Raman and TEM its was observed surface modifications on mwcnt by sintering process and the interaction between mwcnt and TiO2 meanwhile FTIR and UV-Vis allowed to prove that the interaction was carried by a Ti-O-C bonding.