Rapid hydrogenation of amorphous TiO2 to produce efficient H-doped anatase for photocatalytic water splitting

Photoelectrochemical characterization of anatase-rutile mixed TiO2 nanosponges

“…In this way, Figure 4 shows, for instance, the Raman spectra corresponding to the obtained nanotubes (anodized at Re = 0) and nanosponges (anodized at Re = 500), where the characteristic peaks of anatase and rutile phases are presented; i.e. the five allowed modes of anatase: 143 cm −1 (E g ), 197 cm −1 (E g ), 395 cm −1 (B 1g ), 517 cm −1 (A 2g ) and 638 cm −1 (E g ) (indicated as A in Figure 4) [32,33] and the rutile peaks: 144 cm −1 (superimposed with the 143 cm -1 peak of anatase phase) (B 1g ), 235 cm −1 (two-phonon scattering), 445 cm −1 (E g ) and 612 cm −1 (A 1g ) (indicated as R in Figure 4) [33,34] . 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 In order to explain the obtained EIS data, an equivalent electrical circuit with three RC time constants was proposed (Figure 5d).…”

One-Step Synthesis of Metal/Oxide Nanocomposites by Gas Phase Condensation

“…Conversely, at sufficiently high O 2 inlet flow (sample Ti-O_h), it is possible to achieve (almost) full oxidation of the NPs. It is well known that amorphous TiO 2 is obtained when oxidation is carried out close to room temperature, whereas oxidation above 350 °C leads to crystalline TiO 2 [29]. This suggests that NPs oxidation takes place after cool down from the evaporation temperature has taken place via thermalization with the surrounding He gas.…”

Observation of Room-Temperature Ferromagnetism Induced by High-Pressure Hydrogenation of Anatase TiO2

“…Hydrogenation was used in numerous studies to change the chemical, structural, and magnetic properties of materials to achieve carefully tailored functionalities. , In the case of TiO 2 , a well-known photocatalyst, hydrogenation induces the formation of surface-disordered and defect-rich layers TiO 2– x , termed “reduced titania” or “black TiO 2 ”. The presence of oxygen vacancies and Ti 3+ species in TiO 2– x facilitates the electrical conductivity and charge transport, suppressing the recombination of photoinduced electrons and holes, which is beneficial for photocatalytic activity and stability. , In addition, the introduction of abundant lattice disorder and defects extends the photoresponse toward the visible-light region stemming from the band-gap narrowing and the emergence of a defect energy level below the conduction band of TiO 2 , therefore, increasing the quantum efficiency. , …”

“…The presence of oxygen vacancies and Ti 3+ species in TiO 2−x facilitates the electrical conductivity and charge transport, suppressing the recombination of photoinduced electrons and holes, which is beneficial for photocatalytic activity and stability. 27,28 In addition, the introduction of abundant lattice disorder and defects extends the photoresponse toward the visible-light region stemming from the band-gap narrowing and the emergence of a defect energy level below the conduction band of TiO 2 , therefore, increasing the quantum efficiency. 29,30 There are several experimental and theoretical studies on DIM in hydrogenated anatase TiO 2 .…”