Low Temperature Preparation and Characterization of N-doped and N-S-codoped TiO2 by Sol–gel Route

Abstract

This paper reports a new method to prepare the N-doped and N-S-codoped anatase TiO 2 photocatalysts at 100°C. The as-prepared photocatalysts were characterized by means of XRD, Raman spectra, TEM, BET, UV-Vis diffuse reflectance spectra (DRS) and XPS. The results showed that the N-doping and N-S-codoping extended the absorbance spectra of TiO 2 into visible region with different extent. The BET surface area of the N-S-codoped TiO 2 photocatalysts was high up to 245 m 2 g -1 . The results of degradation of methyl orange (MO) solution showed that the N-doped and N-S-codoped TiO 2 photocatalysts exhibited higher photocatalytic activity than that of Degussa P-25 and the as-prepared pure TiO 2 under visible irradiation. This property can be attributed to the results of synergetic effects of absorption in the visible light region, red shift in adsorption edge, good crystallization and large surface area of the as-prepared N-doped or N-S-codoped TiO 2 .

Degradation of organophosphorus flame retardant tris (1-chloro-2-propyl) phosphate (TCPP) by visible light N,S-codoped TiO2 photocatalysts

“…This observation displayed that N,S co-doping could efficiently inhibit grain growth, which is in agreement with the results reported in previous reports [14,13,15,21,25]. Based on previous studies, N,S-codoped TiO 2 catalysts prepared with different TiO 2 and N,S dopant precursors showed a progressive decrease of crystallite size as the N,S-doping increased with crystallite sizes within 5-9 nm [26,54] which are very close to the obtained crystallite sizes in the present study.…”

Preparation, Characterization and Photocatalytic Activity of N doped TiO2

“…Usually amorphous-anatase transformation may complete in the temperature range 250-400 o C. The peak positions are same and no extra peaks except for anatase TiO 2 was observed, suggesting that the structure of TiO 2 is not changed [9]. No peak was observed for dopants, may be due to the low amount of doped nitrogen so that it cannot be detected by XRD.…”

“…The materials show a very high degree of crystallinity of fully anatase phase. The crystallite size of the sample are in arrange of 11-13, which is promising since nanocrystalline anatase is considered as the more photoactive form of titania [9,10].…”

“…N doping can extend the wavelength response range to the visible region and increase the number of photogenerated electrons and holes to participate in the photocatalytic reaction, which would enhance the photocatalytic activity of TiO 2 . However there is no direct relation between light absorption and photocatalytic activity of samples, that stronger absorption of visible light does not mean the higher degradation of pollutants [9,13]. The band gap of N doped titania(U2) is 2.25eV corresponding to 550 nm.…”

Preparation and catalytic activity research of the Sr2MgSi2O7:Eu2+, Dy3+/TiO2 composite catalyst

“…However, only about 5 % of sunlight in the UV region is absorbable for TiO 2 , which greatly limits TiO 2 's practical applications [3,4]. Although various modifications have been devoted to TiO 2 to extend the absorption edge into the visible light in order to enhance the visible light responsive photocatalytic activity [5][6][7][8][9][10][11][12][13], TiO 2 is still useless in dark environments. Thus, some attention has recently been paid to the light resource problem [14].…”