Carrier Transfer and Capture Kinetics of the TiO2/Ag2V4O11 Photocatalyst

Abstract

In this paper, TiO2/Ag2V4O11 nanoheterojunctions have been synthesized by hydrothermal methods, which show enhanced photocatalytic activity compared to TiO2 under visible light. Moreover, the TiO2/Ag2V4O11 nanoheterojunction with set molar ratio of 2:1, referred to as TA2, show the highest visible light photocatalytic activity, which could decompose about 100% RhB molecules within 80 min of irradiation with visible light. Specially, the time-resolved photoluminescence spectrum of TA2 demonstrates that the free exciton recombination occurs in approximately 1.7 ns, and the time scale for Shockley–Read–Hall recombination of photogenerated electrons and holes is prolonged to 6.84 ns. The prolonged timescale of TA2 compared to TiO2 and Ag2V4O11 can be attributed to the carrier separation between nanojunctions and the carrier capture by interfacial defects. Furthermore, the enhanced photocatalytic activity of TiO2/Ag2V4O11 nanoheterojunctions also benefits from the synergistic effect of the broadened absorption region, higher photocarrier generation, longer carrier lifetime, and quicker collection dynamics.

TiO2 Doped with Noble Metals as an Efficient Solution for the Photodegradation of Hazardous Organic Water Pollutants at Ambient Conditions

“…This phenomenon is widely documented in the literature [5,7,43] and occurs on the portion of the surface accessible for the irradiation and adsorption, where the adsorbed pollutant easily interacts with the active oxidizer radicals issued from the interaction between the water molecules and promoted electrons, thus enhancing the photocatalytic performance of the doped catalyst. Indeed, Zhou et al (2020) [50] reported that the redox reactions occurring on the catalyst surface complete the charge carrier recombination, maintaining the photocatalytic activity.…”

Troubleshooting the Limited Zn2+ Storage Performance of the Ag2V4O11 Cathode in Zinc Sulfate Electrolytes via Favorable Synergism with Reduced Graphene Oxides

“…The X-ray powder diffraction (XRD) patterns of as-synthesized Ag 2 V 4 O 11 and Ag 2 V 4 O 11 @rGO-90 samples are shown in Figure a. The XRD pattern demonstrates the crystalline nature of the fabricated materials and matches well with the JCPDS card number 20-1386, corresponding to layered monoclinic Ag 2 V 4 O 11 with the C 2/ m space group. − The crystal structure consists of V 4 O 16 units built from VO 6 distorted octahedral sharing their apexes, which contain infinite V 4 O 16 quadruple strings, and these quadruple strings are further linked by the corner-shared oxygen atoms and thus form [V 4 O 11 ] n layers separated by AgO 5 trigonal bipyramid layers. ,, In the XRD pattern of the composites, no characteristic GO peak at 2θ of ∼10.2° was found, whereas a small hump at 2θ of ∼25.4° appeared, which indicates the reduction of the GO to rGO during the hydrothermal process. The Raman spectra of both Ag 2 V 4 O 11 and Ag 2 V 4 O 11 @rGO-90 showed some identical peaks at ∼209, ∼314, ∼495, ∼673, ∼775, ∼896, and ∼946 cm –1 , respectively, corresponding to Ag 2 V 4 O 11 material (Figure b).…”

Bio-based Au Doping with Dominant Oxygen Vacancies and Ti3+ Defects on Photocatalytic Functionalities of TiO2

“…Compared to Au 0.00 /TiO 2 (bare), τ 2 of Au 1.00 /TiO 2 (bio) was increased from 5.01 to 12.84 ns, which implies delayed Shockley-Read-Hall (SRH) recombination of holes with trapped electrons. A small increment in τ 1 of Au 1.00 /TiO 2 (bio) epitomized the PL of free excitons. , …”

“…A small increment in τ 1 of Au 1.00 /TiO 2 (bio) epitomized the PL of free excitons. 50,51 3.7. Electron Paramagnetic Resonance (EPR).…”