Effect of Transition Metal (Fe, Co) Ion Doping on TiO2 Nano Particles.

Abstract

Keywords: Growth from solution, Nanomaterials, Oxides, Photocatalytic, Sol-Gel method, DMS. . we report the growth of [Fe, Co]xTiO2 (x=0.01, 0.02 & 0.04) Nano quantum dots prepared by Sol-Gel technique, followed by freeze-drying treatment at -30°C temperature for 12hrs. The obtained Gel was thermally treated at different temperature like 200,400,600, 800°C. The crystalline size of 4 to 40 nm is achieved. X-ray diffraction pattern of samples show anatase phases of TiO2, up to 600°C. At 800°C, the phase is Rutile. Figure 1 shows the XRD patterns acquired from different samples heated at different temperatures. The diffraction peak at 25.22°, 25.49°and 25.6° observed from the XRD pattern of the Fe, Co doped TiO2 shows that the main crystal phase is anatase, and the peak at 27.47° indicates the presence of the rutile phase. All the peaks in the XRD patterns of the sample calcined at 200°C, 400°C and 600°C of TM doped TiO2 can be designated to the anatase phase (most active phase) without any indication of other crystalline phases such as rutile or brookite . As a variant valence metal cation, Fe, Co ions can react with Ti4+ on the surface of TiO2, and Ti4+ is reduced to Ti3+ which inhibits the transformation of anatase to rutile [1]. It leads to the reduction in the oxygen vacancies on the TiO2 surface and suppresses the crystallization of other phases by adsorbing onto the surface of the TiO2 particles [2]. The photocatalytic degradation of formaldehyde has been successfully demonstrated using a 250 V UV lamp with TM doped TiO2 nano powder in a specific experimental setup. The degradation rate increases linearly with dopant content increases. This indicates that the photocatalytic reaction in this experiment was effected by dopant concentration. The results obtained in this research contribute to the understanding of binary doped transition metal ions in TiO2 nanoparticles can lead the efforts of enhancing their environmental application. Study of Magnatic proprty has been carried out by using VSM. The magnetic susceptibility of the Fe, Co doped TiO2 nanopowder increases with increase in doping concentration. Fe, Co doped TiO2 exhibits ferromagnetism at room temperature. Figure 1