Synergetic effect of CuS@ZnS nanostructures on photocatalytic degradation of organic pollutant under visible light irradiation

Abstract

Ultrafast visible light active CuS/ZnS nanostructured photocatalysts were synthesized by a hydrothermal method. The effect of the CuS concentration on the morphological, structural and optical properties of ZnS nanostructures were investigated. X-ray diffraction analysis indicated the formation of CuS/ZnS phases with good crystallinity. The presence of ZnS on CuS was confirmed by X-ray photoelectron spectroscopy, elemental mapping, scanning electron microscopy and high resolution transmission electron microscopy analyses. CuS/ZnS nanocomposites efficiently decomposed methylene blue (MB) upon irradiation with visible light. The degradation time was 3 times faster than that of bare ZnS and CuS.The scavenger analysis results revealed that photogenerated superoxide (O 2 À c) radicals were the main reactive species for the degradation of MB. The maximum degradation efficiency of 95.51% was observed within 5 min for samples of 0.050 M CuS/ZnS composites. The obtained results suggested that the enhanced photocatalytic activity was due to the formation of CuS/ZnS heterojunctions which led to the efficient separation of the photoinduced carriers.

Synthesis of CuS and ZnO/Zn(OH)2 nanoparticles and their evaluation for in vitro antibacterial and antifungal activities

“…It exhibits seven major diffraction peaks related to the diffraction angles of 32.3 ° (101), 34.3 ° (102), 37.1 ° (103), 38.2 ° (006), 56.4 ° (110), 62.2 ° (108), and 70.2 ° (116), confirming the formation of a hexagonal covellite phase (CuS) that is in good agreement with the standard XRD pattern (Joint Committee for Powder Diffraction Standards, JCPDS card No. 24–0060) . The average nanocrystalline size (D) estimated by Debeye‐Scherrer equation based on the full width at half maximum of the most intense peak (110) was estimated to be about 20 nm, which supports the nanocrystalline size obtained from TEM images.…”

Mechanistic Insights into Photodegradation of Organic Dyes Using Heterostructure Photocatalysts

“…In addition to these operational parameters, the band position and charge-carrier utilization of the photocatalysts also have an impact on the generation of reactive radicals and the subsequent photodegradation performance. To improve the carrier utilization and thereby achieve efficient reactive radical generation, heterostructure photocatalysts with enhanced photocatalytic activity are proposed and employed [18][19][20][21][22][23][24][25].…”

Morphological studies and photocatalytic degradation of methylene blue by zinc sulfide nanoparticles

“…Therefore, OH is a dominant reactive species that took part in the photodegradation of methylene blue over oleylamine-capped ZnS nanoparticles. As a result of hydroxyl radical scavenging, there is a possibility that the rate of reaction will increase due to reduction of electron-hole pair recombination [35,36].…”