BiVO4/TiO2 nanocrystalline heterostructure: A wide spectrum responsive photocatalyst towards the highly efficient decomposition of gaseous benzene

Composite photocatalyst films have been fabricated by depositing BiVO4 upon TiO2 via a sequential ionic layer adsorption reaction (SILAR) method. The photocatalytic materials were investigated by XRD, TEM, UV/Vis diffuse reflectance, inductively coupled plasma optical emission spectrometry (ICP-OES), XPS, photoluminescence and Mott-Schottky analyses. SILAR processing was found to deposit monoclinic-scheelite BiVO4 nanoparticles onto the surface, giving successive improvements in the films' visible light harvesting. Electrochemical and valence band XPS studies revealed that the prepared heterojunctions have a type II band structure, with the BiVO4 conduction band and valence band lying cathodically shifted from those of TiO2 . The photocatalytic activity of the films was measured by the decolourisation of the dye rhodamine 6G using λ>400 nm visible light. It was found that five SILAR cycles was optimal, with a pseudo-first-order rate constant of 0.004 min(-1) . As a reference material, the same SILAR modification has been made to an inactive wide-band-gap ZrO2 film, where the mismatch of conduction and valence band energies disallows charge separation. The photocatalytic activity of the BiVO4 -ZrO2 system was found to be significantly reduced, highlighting the importance of charge separation across the interface. The mechanism of action of the photocatalysts has also been investigated, in particular the effect of self-sensitisation by the model organic dye and the ability of the dye to inject electrons into the photocatalyst's conduction band.

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“…This structure is in agreement with that described recently by Hu et al 52 , Sun et al 53 , and Sun et al 31 for BiVO4-TiO2 heterojunctions.…”

Section: Band Structuresupporting

confidence: 91%

BiVO₄‐TiO₂ Composite Photocatalysts for Dye Degradation Formed Using the SILAR Method

Odling

Robertson

2016

ChemPhysChem

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“…36,37 However, in these later cases m-BiVO 4 has been considered. Taking into account mBiVO 4 conduction and valence bands position with respect to TiO 2 , it is clear that an unfavourable situation is taking place.…”

Section: 35mentioning

confidence: 99%

A ternary Er3+-BiVO4/TiO2 complex heterostructure with excellent photocatalytic performance

Obregón

Colón

2014

RSC Adv.

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Ternary erbium doped BiVO 4 /TiO 2 complexes are synthesized by means of a simple impregnation method with good photoactivities under sun-like excitation for the degradation of phenol. From the structural and morphological characterization it has been stated that the presence of Er 3+ induces a slight stabilization of the tetragonal phase probably due to its incorporation in the BiVO 4 lattice. Therefore a ternary heterostructured material has been obtained. The best photocatalytic performance was attained for the samples with 1 wt% of Er 3+ -doped BiVO 4 content with respect to TiO 2 . The occurrence of a complex structural mixture with the adequate band position leads to effective charge pair separation which induces higher photocatalytic activities.

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“…Figure 6c,d shows the UV-vis absorption spectral changes of the MB solution by OH-TiO2 and F-TiO2, respectively. According to previous research, two processes can cause the discoloration of MB: oxidative degradation and two-electron reduction to leuco-MB which can be detected by the UVvis absorption at 256 nm [43,44]. From Figure 6d, a blue-shift from 665 to 625 nm and an absorbent peak at 256 nm emerged in the spectral change of MB with irradiation on OH-S0.…”

Section: Photocatalytic Activitymentioning

confidence: 99%

Low Temperature Synthesis of Nest-Like Microsphere with Exposed (001) Facets and Its Enhanced Photocatalytic Performance by NaOH Alkalization

2018

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Abstract:In this study, we completed a simple low-temperature synthesis of nest-like titanium oxide (TiO 2 ) microspheres with exposed (001) facets. For the first time, the photocatalytic performance was enhanced by sodium hydroxide (NaOH) alkalization. The characterization of as-synthesized F-TiO 2 and OH-TiO 2 were analyzed by field emission scanning electron microscopy, high-resolution transmission electron microscopy, X-ray diffraction, fourier transform infrared spectroscopic analysis, ultraviolet-vis diffuse reflection spectra and Raman spectroscopy. The photocatalytic activity of the as-prepared catalyst was evaluated through the photocatalytic degradation of methylene blue (MB) and Rhodamine B (RhB) under simulated solar light. The results showed that modification using NaOH can lead to an increase in the percentage of (001) facets from 27.8% for F-TiO 2 to 39.2% for OH-TiO 2 . OH-TiO 2 showed superior catalytic photoactivity toward MB. The mechanism of NaOH on TiO 2 is also discussed.

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BiVO4/TiO2 nanocrystalline heterostructure: A wide spectrum responsive photocatalyst towards the highly efficient decomposition of gaseous benzene

Cited by 295 publications

References 27 publications

BiVO₄‐TiO₂ Composite Photocatalysts for Dye Degradation Formed Using the SILAR Method

BiVO₄‐TiO₂ Composite Photocatalysts for Dye Degradation Formed Using the SILAR Method

A ternary Er3+-BiVO4/TiO2 complex heterostructure with excellent photocatalytic performance

Low Temperature Synthesis of Nest-Like Microsphere with Exposed (001) Facets and Its Enhanced Photocatalytic Performance by NaOH Alkalization

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BiVO4/TiO2 nanocrystalline heterostructure: A wide spectrum responsive photocatalyst towards the highly efficient decomposition of gaseous benzene

Cited by 295 publications

References 27 publications

BiVO4‐TiO2 Composite Photocatalysts for Dye Degradation Formed Using the SILAR Method

BiVO4‐TiO2 Composite Photocatalysts for Dye Degradation Formed Using the SILAR Method

A ternary Er3+-BiVO4/TiO2 complex heterostructure with excellent photocatalytic performance

Low Temperature Synthesis of Nest-Like Microsphere with Exposed (001) Facets and Its Enhanced Photocatalytic Performance by NaOH Alkalization

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Product

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BiVO₄‐TiO₂ Composite Photocatalysts for Dye Degradation Formed Using the SILAR Method

BiVO₄‐TiO₂ Composite Photocatalysts for Dye Degradation Formed Using the SILAR Method