Gentle way to build reduced titanium dioxide nanodots integrated with graphite-like carbon spheres: From DFT calculation to experimental measurement

Abstract

Extending the ultraviolet response of anatase TiO 2 into visible light range and effectively decreasing the recombination rate of photo-generated carriers are vital to promote the practical applications in the fields of hydrogen generation and water pollutant treatment of TiO 2-based photocatalysts. Here we present a mild way to build composite of partial reduced TiO 2 nanodots coated graphite-like carbon spheres (g-CS@TiO 2-X) via a green solvothermal approach with relative low temperature. The chemical structure and electronic property of 3D g-CS@TiO 2-X composites have been investigated by DFT. Our DFT calculation results indicates that some mid-levels are formed between the CB and VB of TiO 2-X , which is beneficial to its visible absorption ability. The calculation results also show that bridge of Ti-O-C formed between g-CS and TiO 2-X may let the composite possesses superior charge separation property. The experimental results demonstrate that the obtained 3D g-CS@TiO 2-X can serve as an effective visible-light-driven photocatalyst for hydrogen production and organic pollutants degradation. The good visible light absorption introduced by Ti 3+ and 3D g-CS, the well-known electron transfer capability of g-CS, the matched electron structures of TiO 2-X and g-CS, and perfect interface between TiO 2-X and g-CS (Ti-O-C bridge), efficiently boost visible light photocatalytic performance via one-level electron transfer process.

Efficient Degradation of Phenol and 4‐Nitrophenol by Surface Oxygen Vacancies and Plasmonic Silver Co‐Modified Bi2MoO6 Photocatalysts

“…Recent results revealed that higher intensity means ah igher rate of photogenerated electron-and-hole recombination. [57] Clearly, 2%A/BMO-SOVs-375 exhibits the lowest PL signal in comparison with BMO and BMO-SOVs-375, suggestingt hat the recombination rate of photoinduced electron-hole pairs was efficiently inhibited by the modification of SOVs and metallicA gn anoparticles on the surfaceo fB MO. This effect is furtherc onfirmed by the time-resolved photoluminescence (TR-PL) analysis.…”

“…To investigate the generation, transfer, and recombination of photogenerated electron–hole pairs on the semiconductor, photoluminescence (PL) emission spectra were recorded, and the results are shown in Figure a. Recent results revealed that higher intensity means a higher rate of photogenerated electron‐and‐hole recombination . Clearly, 2 %A/BMO‐SOVs‐375 exhibits the lowest PL signal in comparison with BMO and BMO‐SOVs‐375, suggesting that the recombination rate of photoinduced electron–hole pairs was efficiently inhibited by the modification of SOVs and metallic Ag nanoparticles on the surface of BMO.…”

TiO2 as a Photocatalyst for Water Splitting—An Experimental and Theoretical Review

“…Experimental studies shown in Figure 6 c confirmed these findings. By using graphite carbon spheres on TiO 2 Jiang et al introduced isolated energy levels between the VBM and the CBM [ 103 ]. These intermediate bandgaps increase the number of electrons that could be excited from the VB to the CB.…”

Boosted Charge Transfer Efficacy of an All‐Solid‐State Z‐Scheme BiOI‐CD‐CdS Photocatalyst for Enhanced Degradation of 4‐Nitrophenol and Oxidation of Benzyl Alcohol under Visible Light**

“…Low PL emission intensity indicates good separation efficiency of charge carriers. [48] PL spectra of BiOI display a strong emission peak at around 542 nm and CdS exhibits a broad emission peak at around 565 nm at an excitation wavelength of 375 nm. PL intensity for 10 wt% BiOI-CdS and 10 wt % BCC gets significantly reduced compared to both BiOI and CdS.…”