A novel 3D/2D CdIn₂S₄ nano-octahedron/ZnO nanosheet heterostructure: facile synthesis, synergistic effect and enhanced tetracycline hydrochloride photodegradation mechanism

Abstract

In this work, 3D CdIn2S4 nano-octahedron/2D ZnO nanosheet heterojunctions (CIS/ZO-x) were fabricated for the first time via a facile and green impregnation-hydrothermal method, where three-dimensional (3D) CdIn2S4 nano-octahedra densely anchor onto both sides of 2D ZnO nanosheets to form an embedded nanostructure with intimate interfacial contacts. Various characterization techniques were adopted to measure the morphologies, structures and optical properties of the as-prepared CIS/ZO-x heterojunctions in detail. The photocatalytic performance of the as-prepared CIS/ZO-x was evaluated via the photodegradation of tetracycline hydrochloride (TCH) under visible light irradiation, and the result shows that the hybridization of ZnO nanosheets with CdIn2S4 nano-octahedra significantly enhances the photocatalytic activity of heterojunctions. The highly stable and reusable sample CIS/ZO-2 possesses the highest photocatalytic activity (94.04%), and its rate constant (k = 0.06357 min-1) is about 4.96 and 22.31 times as high as those of pure CdIn2S4 and ZnO. Interestingly, the removal efficiency of TCH and the rate constant are also much higher than those of numerous previously reported composite photocatalysts. The synergistic effect and the unique 3D/2D hybrid structure with intimate interfacial contacts are primarily responsible for the enhanced photocatalytic activity. A possible photocatalytic mechanism for the TCH photodegradation over the CIS/ZO sample is also proposed. This work provides a novel 3D/2D composite photocatalyst for the efficient removal of antibiotic pollutants and will be helpful for designing other 3D/2D heterojunctions.

Study on the Photocathodic Protection of Q235 Steel by CdIn2S4 Sensitized TiO2 Composite in Splash Zone

“…As a narrow band gap (2.1 eV) semiconductor material, CdIn 2 S 4 is an ideal material for improving the visible light response of semiconductor composites [24][25][26][27][28][29]. The conduction band (−0.76 eV) of CdIn 2 S 4 is more negative than that of TiO 2 (−0.29 V versus NHE), which could cause the negative shift of the Fermi level of TiO 2 .…”

Constructing CuBi2O4/Ag3PO4 Photocatalyst with Improved Photocatalytic Performance for the Degradation of Tetracycline under Visible‐Light Irradiation

“…In recent years, photocatalytic technology has been paid more attention by researchers due to its simple, lowcost and high efficiency to dispose organic pollutants from water. [5][6][7][8] Among, CdS, [9] ZnSe, [10] BiVO 4 , [11,12] Bi 2 WO 6 , [13,14] g-C 3 N 4 [15][16][17] and other materials [18][19][20][21] can be used as photocatalysts to degrade TC or pollutants in solution. Nevertheless, it is unable to meet the large-scale practical application of TC treatment due to low visible-light photocatalytic activity, photo-corrosion, instability, incompatible with earthly life.…”

Photocatalytic Degradation of Tetracycline by ZnO/γ-Fe2O3 Paramagnetic Nanocomposite Material

“…Although numerous studies on the removal of tetracyclines from water using ZnO as catalyst have already been reported [ 21 , 22 , 23 , 24 ], in this work, we propose the synthesis of a new nanocomposite material based on zinc oxide and paramagnetic iron oxide, in particular an oxide of Fe(III) in gamma phase (γ-Fe 2 O 3 ), employed as catalyst to induce TC degradation in aqueous solutions. The obtained nanocomposite catalyst (ZnO/γ-Fe 2 O 3 ) has the advantage of being easily separated from water after the photocatalytic process by means of the application of a weak external magnetic field, so the presence of paramagnetic γ-Fe 2 O 3 nanoparticles in the ZnO/γ-Fe 2 O 3 allows a very simple recovery of catalyst and its possible reuse in other degradation cycles.…”