Nd가 도핑된 TiO2 광촉매의 제조와 특성

초록

TiO2 is widely used as phocatalyst because of its optical and electronic properties, low cost, chemical stability and non-toxicity. Due to its band gap energy, TiO2 utilizes only a very small fraction of the solar spectrum and thus doping with metal ion has been employed to shift the light absorption to the visible region. In the present study, titania doped powder doped by the Neodymium was characterized by XRD, SEM, UV-Visible spectrometer. The photoactivity of the doped photocatalyst is characterized by photocatalytic decomposition of dichlorobenzene (DCB) in suspended aqueous solution. Neodymium doped TiO2 powder as a photocatalyst were prepared by sol-gel process. The determined amount of titanium isopropoxide (Ti(OC3H7)4) and neodymium nitrate was dissolved in isopropanol under stirring to form precursor solution. Glacial acetic acid as a catalyst was added into the solution and acetylacetone was added into the solution to stabilized it. The precursor solution was heated at 120 ℃ in the oven to remove solvent and some organic matters. Thus dry powders were obtained. The dried powders calcined at temperature from 500-900℃ for 2 hours in the furnace. X-ray diffraction and scanning electron microscopy were applied for microstructural studies. Optical properties of the doped TiO2 powders were studied by UV-Visible-Spectrometer. Photocatalytic activity of each doped TiO2 was characterized in terms of the degradation of a dichlorobenzene. XRD analysis indicated that the doping of neodymium suppress the phase transition of TiO2 from anatase to rutile. The sample heat-treated at 500℃ exhibited anatase phase, while anatase phases were remained in the samples heat-treated over 700℃. Diffuse reflectance spectra showed that a strong absorption at visible region is attributed to the absorption of neodymium by nature. Also Nd-doped TiO2 powders exhibited better photocatalytic active than the undoped TiO2.