Photocatalytic Hydrogen Production and Tetracycline Degradation Using ZnIn2S4 Quantum Dots Modified g-C3N4 Composites

Abstract

In this work, ZnIn2S4/g-C3N4 (ZIS/CN) composites were synthesized by in-situ growth method, which showed excellent photocatalytic activity in the degradation of tetracycline and hydrogen production from water under visible light irradiation. ZnIn2S4 quantum dots (ZIS QDs) tightly combined with sheet g-C3N4 (CN) to accelerate the separation and transportation of photogenerated charges for enhanced photocatalytic activity. Among the prepared nanocomposites, 20%ZnIn2S4 QDs/g-C3N4 (20%ZIS/CN) delivered the highest photocatalytic activity. After 120 min of irradiation, the degradation rate of tetracycline with 20%ZIS/CN was 54.82%, 3.1 times that of CN while the rate of hydrogen production was 75.2 μmol·g−1·h−1. According to the optical and electrochemical characterization analysis, it was concluded that the excellent photocatalytic activities of the composite materials were mainly due to the following three points: enhancement in light absorption capacity, acceleration in the charge transport, and reduction in the carrier recombination rate through the formation of S-scheme heterojunction in the composite system. The high photocatalytic activity of ZIS/CN composites provides a new idea to develop highly efficient photocatalysts.

Fe3O4@MIL-100(Fe) modified ZnS nanoparticles with enhanced sonocatalytic degradation of tetracycline antibiotic in water

“…4 b shows the XPS peak of Zn 2p. The binding energy peaks at 1021.2 and 1044.3 eV are attributed to the spin-orbital splitting of Zn 2+ corresponding to Zn 2p 3/2 and Zn 2p 1/2 , respectively [26] . In addition, a signal peak of Zn LM2 appears at 498.5 eV and is caused by the Auger electrons of Zn [27] .…”

“…6 a, it is clear that as the number of catalyst increases, the sonocatalytic removal of tetracycline first increases and then decreases. This indicates that the excessive addition of 20FM/ZnS can cause agglomeration of the catalyst, which may mask each other's active sites [26] . At the same time, the addition of excessive catalyst has a certain barrier to the propagation of sonoluminescence which reduces the catalytic activity of the catalyst itself [29] .…”

Regulating Deep and Shallow Defects of CuInS2 Quantum Dots To Enhance Photocatalytic Hydrogen Production

“…The use of fossil fuels also releases large amounts of greenhouse gases (CO 2 ), and the concentration of carbon dioxide in the atmosphere has increased from 280 ppm before preindustrial period to 413.2 ppm. , As an efficient and clean energy source, hydrogen energy has the advantages of being storable and renewable and has the highest energy density (142 MJ·kg –1 ) among all chemical fuels, which makes it a hot research topic for alleviating energy shortage and environmental pollution . Using photocatalytic decomposition of water to produce H 2 is one of the most ideal ways to fundamentally solve the energy and environmental problems and also the way to prevent the environmental pollution caused by fossil energy. − Semiconductor QDs are a widely studied new catalyst in the field of solar hydrogen production. − Recently, various semiconductor QDs have been widely studied as photoabsorbers in heterogeneous or homogeneous photocatalytic systems. − Unfortunately, early QDs maintained a low photocatalytic efficiency due to excessive electron–hole recombination, poor exciton separation efficiency, and limited active sites. Thereafter, strategies such as surface engineering, element doping, , loading cocatalyst, defect engineering, − and heterojunction have been developed to improve the photocatalytic efficiency.…”

Biogenic Preparation of ZnO Nanostructures Using Leafy Spinach Extract for High-Performance Photodegradation of Methylene Blue under the Illumination of Natural Sunlight

“…Research on the proposed project aims at enhancing photocatalysis through the development of new classes of materials or the modification of surfaces. Therefore, a great deal of research has been conducted regarding the development of active photocatalytic materials [ 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 ]. In comparison to other metal oxide semiconductors, titanium dioxide (TiO 2 ) is effective in removing dyes from water effluents, but it has been well-explored to synthesize inexpensive ZnO photocatalysts for removing synthetic organic dyes from aqueous solutions [ 32 , 33 , 34 ].…”