Surface defect (Ti3+) controlling in the first step on the anatase TiO2 nanocrystal by using sol–gel technique

Properties of transition metal doped-titania electrodes: Impact on efficiency of amorphous and nanocrystalline dye-sensitized solar cells

“…Pure and selected metal transition (M)-doped TiO 2 powders, where M is Mn 2 þ , Co 2 þ , Cu 2 þ , were prepared by a sol-gel technique [21,22]. Titanium isopropoxide (Ti (OC 3 H 7 )) was used as TiO 2 precursor.…”

Preparation of Ti3+ self-doped TiO2 nanoparticles and their visible light photocatalytic activity

“…Because the degree of surface oxidization of the yellow gel was higher than that of the green gel, its content of TiH2 was lower, so pure anatase phase Ti 3+ self-doped TiO2 nanoparticles were obtained after only a short hydrothermal treatment time. Compared with the use of tetrabutyl titanate as the raw material to prepare TiO2 containing surface Ti 3+ [35,36], our adoption of a low valent titanium compound as the raw material means that during the initial stage of the reaction, the Ti 2+ ions located on the particle are converted to TiO2 contains Ti 3+ in both the lattice and surface through ion diffusion and exchange reactions, which ensures the stability of the material. Meanwhile, using H2O2 as an oxidant can guarantee the purity of the product, and controlling the degree of oxidation of TiH2 and the subsequent hydrothermal treatment conditions allows the content of Ti 3+ and Ov in the final products to be controlled to adjust their catalytic performance.…”

Ti3+ in the Surface of Titanium Dioxide: Generation, Properties and Photocatalytic Application

“…The electrons are stored in the gel network as small polarons, Ti 3+ centers, whereas the holes are stored in the liquid phase as H + ions or radicals. Some other research groups also reported the generation of Ti 3+ defects by UV irradiation [68,69] [63] reported that low-temperature vacuum annealing could create a controlled number of TSD ranging from low concentration (<3% Ti 3+ /Ti 4+ ) to high concentration (around 21% Ti 3+ /Ti 4+ ) at 323 and 573 K, respectively. Figure 3 shows the variation of the Ti 3+ to Ti 4+ ratio with vacuum annealing temperature.…”