Homojunction and defect synergy-mediated electron–hole separation for solar-driven mesoporous rutile/anatase TiO₂ microsphere photocatalysts

Abstract

Mesoporous rutile/anatase TiO2 microspheres with surface defects are fabricated and exhibit excellent solar-driven photocatalytic performance due to synergistic effect of the homojunction and surface defects favoring efficient e–h separation.

Black TiO2-Based Dual Photoanodes Boost the Efficiency of Quantum Dot-Sensitized Solar Cells to 11.7%

“…Shown in Figure 4 are the UPS spectra of anatase TiO 2 and rutile TiO 2 before and after laser treatment. Both results indicate that the top of the valence band of black TiO 2 is lower than that of pristine TiO 2 , which is consistent with previous reports [ 14 , 15 , 18 ]. From the UV–vis absorption spectra ( Figure 5 a) and diffuse reflectance spectra ( Figure S2b in the Supplementary Materials ) of the six samples it can be seen that the main absorption of the six samples occurs in the spectral range of less than 400 nm, mainly due to the inherent bandgap of TiO 2 (3.02–3.20 eV) [ 34 ].…”

“…The characteristic peaks of anatase TiO 2 and rutile TiO 2 can be observed in FTIR spectra of P25 TiO 2 and black P25 TiO 2 in Figure 2 f. In the Raman spectra ( Figure S1 in the Supplementary Materials ), it can be seen that there are no significant shifts in the Raman peak positions for the black TiO 2 , while the bands seem slightly smaller than the pristine TiO 2 in all three cases. This indicates that there is no significant difference between black TiO 2 and white TiO 2 in structure and functional groups [ 17 , 18 , 19 ].…”

“…Some researchers inferred that the color change in TiO 2 NPs may be related to the increase in the oxygen vacancy concentration, leading to a narrower bandgap and redshift in the absorption spectrum to the visible and even the infrared region [ 14 , 15 , 16 ]. In contrast, some researchers believe that the increase in oxygen vacancy concentration and the doping of other elements would not narrow the bandgap of TiO 2 , and the significant redshift in the absorption spectrum is owing to the amorphous surface state of black TiO 2 [ 17 , 18 , 19 ]. In spite of the argument around the mechanism of black TiO 2 , including the effects of oxygen vacancies, Ti 3+ , and doped elements [ 20 , 21 , 22 , 23 ], it is clear that black TiO 2 exhibits enhanced and extended light absorption, which is expected to improve the performance of QDSSCs [ 24 , 25 , 26 , 27 ].…”

Efficient non-metal based conducting polymers for photocatalytic hydrogen production: comparative study between polyaniline, polypyrrole and PEDOT

“… 7–9 Until this day, TiO 2 attracted a broad attention as a photocatalyst due to its availability, chemical stability, non-corrosive and catalytic activity. 10,11,72 However, the wide optical band gap of TiO 2 (3.2 eV) restricts its ability to harness visible light. Furthermore, it suffers from a high recombination rate of photogenerated charge carriers and low catalytic active sites with low overpotential.…”

Photocatalytic improvement of Y3+ modified TiO2 prepared by a ball milling method and application in shrimp wastewater treatment

“…17 In order to improve its photocatalytic activity and practical applications, many efforts have been made, such as element doping, semiconductor coupling and noble metal deposition. 18 Lots of researches suggest that the TiO 2 photocatalysts doping with nonmetal or metal exhibit visible light response and excellent photocatalytic activity. 19 A growing number of experimental and theoretical researches have been concentrated on rare earth metal doped TiO 2 photocatalysts recently.…”