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Abstract. The incorporation of cadmium sulfide (CdS) into TiO2 nanoparticle thin films was investigated. The nanoparticle TiO2 thin film onto an indium dopedtin oxide (ITO) substrate was deposited by Electron Beam Deposition (EBD) combined with thermal process. Then a CdS thin film was vacuum-deposited onto the pre-deposited TiO2 film by a thermal evaporation technique. The obtained TiO2/CdS was characterized by X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM). The TiO2/CdS nanocomposite film was used in a photoelectrochemical (PEC) cell as a working electrode and a platinum electrode as a counter electrode. The electrolyte solution contains 1 M KCl and 0.1M Na2S. The results show that the cell with TiO2/CdS composite film electrode has significantly improved photoelectric capability in comparison with that of the pure TiO2 thin films.

Sodium manganese oxide (Na x MnO 2 ) has attracted much attention as cathode materials for alkaline ion battery due to the ability of the fast charge and discharge of Na + , in particular in nanoscale. We report on the synthesis of Na x MnO 2 nanowires via hydrothermal synthesis route from Mn 2 O 3 and NaOH solution. The morphological observation indicates that the obtained Na 0.44 MnO 2 nanowires with diameters of about 20 nm -30 nm, length up to several micrometers were formed by this process. The electrochemical properties of fabricated materials were investigated by means of cyclic voltammetry technique and show that sodium manganese oxide (Na x MnO 2 ) is a promising material used for the alkaline ion battery.

In this work, TiO\(_{2}\) nanocrystalline thin films were obtained through evaporating Ti films by Electron Beam Deposition (EBD) followed by thermal treatment. The deposition speed of Ti thin fims was carried out at 0.15 nm/s and 1 nm/s. The results show that after annealing at 450\(^\circ\)C for 8 h, the obtained TiO\(_{2}\) thin films have nanoparticle structure with grain size of 20 nm for the Ti thin film deposited at the rate of 1nm/s, whereas at the a deposition rate of 0.15 nm/s, the TiO\(_{2}\) has a nanorod structure with the rod length of 300 -- 400 nm. At 700\(^\circ\)C for 8 h, the rutile phase was formed. At annealing temperature of 450\(^\circ\)C, all the samples are close to the stress free TiO\(_{2}\). The band gap of TiO\(_{2}\) thin films decreased with annealing temperature in both doposition rate of Ti thin films. The response of the films annealed at 450\(^\circ\)C presented a faster rise and fall in photocurrent under UV illumination on and off interval. Nanoporous structure TiO\(_{2}\) shows photoelectronic property better than that of nanorod structure. The obtained TiO\(_{2}\) films were characterized by X-ray diffraction (XRD) and a field emission scanning electron microscope (FE-SEM). The TiO\(_{2}\) films were used in a photo-electrochemical (PEC) cell as a working electrode and a platinum electrode as a counter electrode. The electrolyte solution contains 1 M KCl and 0.1 M Na\(_{2}\)S.

In this work, NaNi0.5Ti0.5O2 cathode materials of sodium ion batteries were synthesized by a pre-milling combined with solid-state reaction method using sodium hydroxide (NaOH), nickel (II) acetate (2(CH3COO)Ni.4H2O), and titanium dioxide (TiO2) as the precursors. Results of X-ray diffraction analysis of the materials obtained after the milling and calcination processes revealed that the increment of the pre-milling time improved the reactivity of NaOH and TiO2, thereby significantly reduced the content of NiO impurity in the NaNi0.5Ti0.5O2 product. The as-synthesized cathode material possessed an excellent electrochemical performance with 77% capacity (compared to the second cycle) retained after 50 cycles of charge/discharge, and 60% capacity retention when the rate of charge/discharge increased from 0.5 to 8 C.

Ni-substitution spinel LiNixMn2−xO4 (x = 0, 0.1, 0.2) materials were synthesized by the sol--gel method. The structure and  morphology of the samples were characterized by the X-ray diffraction (XRD)  and the scanning electron microscopy. The ac conduction of the materials was  investigated by electrochemical impedance spectroscopy (EIS) measurements.  The refinement results showed that the substitution of Ni decreased the  lattice constant and Mn--O distance, while increased Li--O bond length and  16c octahedral volume. The EIS results confirmed the decrease of  conductivity with increasing Ni substitution content. Based on XRD and EIS  results, the relationship between the crystal structure and electrochemical  behavior of the materials was discussed and explained.

Abstract. In this work, TiO2 nanocrystalline thin films were obtained through evaporating Ti films by Electron Beam Deposition (EBD) followed by thermal treatment. The deposition speed of Ti thin fims was carried out at 0.15 nm/s and 1 nm/s. The results show that after annealing at 450˚C for 8 h, the obtained TiO2 thin films have nanoparticle structure with grain size of 20 nm for the Ti thin film deposited at the rate of 1nm/s, whereas at the a deposition rate of 0.15 nm/s, the TiO2 has a nanorod structure with the rod length of 300 -400 nm. The influence of thermal annealing on structure of TiO2 films have been investigated and indicated that when annealed at 450˚C for 8 hours, all the Ti films were completely oxidized to form TiO2 films with anatase phase. Whereas, at 700˚C the rutile phase was formed. The band gap of TiO2 thin films decreased with annealing temperature in both doposition rate of Ti thin films. The response of the films annealed at 450˚C presented a faster rise and fall in photocurrent under UV illumination on and off interval. Nanoporous structure TiO2 shows photoelectronic property better than that of nanorod structure. The TiO2 films were used in a photo-electrochemical (PEC) cell as a working electrode and a platinum electrode as a counter electrode. The electrolyte solution contains 1 M KCl and 0.1 M Na2S.