Facile Synthesis of g-C3N4/TiO2/Hectorite Z-Scheme Composite and Its Visible Photocatalytic Degradation of Rhodamine B

Abstract

A novel g-C3N4/TiO2/hectorite Z-scheme composites with oxygen vacancy (Vo) defects and Ti3+ were synthesized by so-gel method and high temperature solid phase reaction. This composite exhibited high visible photo-catalytic degradation of rhodamine B (RhB). The apparent rate constant of g-C3N4/TiO2/hectorite was 0.01705 min−1, which is approximately 5.38 and 4.88 times that of P25 and g-C3N4, respectively. The enhancement of photo-catalytic efficiency of the composites can be attributed to the great light harvesting ability, high specific surface area and effective separation of electrons(e−) and holes(h+). The F element from Hectorite causes the formation of Vo and Ti3+ in TiO2, making it responsive to visible light. The effective separation of e− and h+ mainly results from Z-scheme transfer of photo-produced electrons in g-C3N4/TiO2 interface. The composites can be easily recycled and the degradation rate of the RhB still reached 84% after five cycles, indicating its good reusability.

Synthesis of CdS/g‐C3N4/Vermiculite Heterostructures with Enhanced Visible Photocatalytic Activity for Dye Degradation

“…On the other hand, natural minerals have high adsorption capacity, high thermochemical stability, low cost, convenient recycling, and rich content, which are good choices for the construction of macrosystems, such as kaolinite, [20] montmorillonite, [21] or zeolite. [22,23] Among them, vermiculite is a phyllosilicate mineral montmorillonite similar, which means a layer of the tetrahedral and octahedral ratio of 2 : 1 arrangement of composition, a thickness of about 1 nm or so, between the cell layer 2 is a layer of water molecules.…”

One-Pot Synthesis of TiO2/Hectorite Composite and Its Photocatalytic Degradation of Methylene Blue

“…It can be observed that hectorite has low crystallinity and small particle size from the widened peaks. Some weak peaks of 2θ appear at 29.0, 32.0, 38.7, 48.9, and 54.7 • , which may be attributed to the residual starting materials and some intermediate products, such as lithium fluoride, lithium, and silicate [10]. Mx[LixMg6−xSi8O20(OH)yFz] ( M = Na , Li) [10,11].…”

“…Some weak peaks of 2θ appear at 29.0, 32.0, 38.7, 48.9, and 54.7 • , which may be attributed to the residual starting materials and some intermediate products, such as lithium fluoride, lithium, and silicate [10]. Mx[LixMg6−xSi8O20(OH)yFz] ( M = Na , Li) [10,11]. Hectorite can facilitate the separation of composites and improve the recycling of catalysts [12].…”

“…Some weak peaks of 2θ appear at 29.0, 32.0, 38.7, 48.9, and 54.7°, which may be attributed to the residual starting materials and some intermediate products, such as lithium fluoride, lithium, and silicate [10]. , which correspond to the diffraction planes of (101), (004), ( 200), ( 105), (211), and (204) [10]. The same diffraction peaks are found for the TiO 2 /hectorite photocatalysts with different molar ratios of Li, Mg, and Si.…”

“…The interlayer cations in the composite clays tend to capture electrons and oxidize the holes, thus reducing the charge recombination rate and improving the photocatalytic performance. Hectorite belongs to 2:1-type layered clay composed of a Si-O tetrahedron and a Mg-O octahedron arranged in 2:1 order in the vertical direction, and its molecular structure is M x [Li x x Si 8 O 20 (OH) y F z ] ( M = Na, Li) [10,11]. Hectorite can facilitate the separation of composites and improve the recycling of catalysts [12].…”