Preparation of anatase F doped TiO2 sol and its performance for photodegradation of formaldehyde

Effect of Electronegativity and Charge Balance on the Visible-Light-Responsive Photocatalytic Activity of Nonmetal Doped Anatase TiO2

“…It is apparent that the impurity states induced by N and F doping locate in different range of the valence band, which can be ascribed to their unique electronegativities as we discussed above. Obviously, the absorption edge of new band in the visible light originated from the doped N atoms rather than doped F atoms, consistent with the former studies [36,37]. Furthermore, the impurity states are fully filled with the electrons at the ground state, which can be attributed to the fact that the doped F − ion compensates the charge of N 3− ion.…”

“…When the nonmetallic elements are brought to the bulk TiO 2 , charges will redistribute until the electrochemical potentials of the compound reach equilibrium. To unravel the inherent relationship of the electronic properties induced by different doping species, which possessed unique electronegativity, the total density of state (TDOS) and projected density of state (PDOS) for the doped TiO 2 are calculated and displayed in Figure [36,37]. It is noticed that the electronegativity mainly determines the properties of the outermost atomic orbitals, which simultaneously influence the impurity states induced by F doping.…”

Semiconducting Materials

“…More recently, increased adsorption capacity of F-TiO 2 due to the larger number of acid sites in the doped material was reported (Li et al 2005;Huang et al 2007). The higher electronegativity of fluorine makes the neighboring titanium atom more "positively charged" acting as Lewis acidic sites and improving the interaction with polar organic compounds.…”

“…The higher electronegativity of fluorine makes the neighboring titanium atom more "positively charged" acting as Lewis acidic sites and improving the interaction with polar organic compounds. The effect of F/Ti atomic ratio on the crystallinity of the material and photodegradation rate of formaldehyde was evaluated (Huang et al 2007). It was observed that a F:Ti ¼ 0.03 was optimal for degradation, whereas the crystallinity of the materials was increased linearly with dopant concentration.…”

Synergistic Effects of Phosphorus and Cobalt Binary Doping on Visible Light Activity of TiO2 by Sol-Gel Method and Evaluation of Photocatalytic Efficiency

“…To obtain the visible light active TiO2 many attempts has been made to get visible light activity by many researches has been carried out by doping with metals [3][4][5][6][7], non-metal [8][9][10][11][12][13][14][15], and codoping [16] with metal-metal and metal-nonmetal. Among these codoping combinations metal-nonmetal codoping shows improved the photocatalytic activity of TiO2 in visible light due to enhancing the electron-hole pairs separation, reduced electron recombination processes, decrease in grain size and active under visible light irradiation.…”