Unravelling the promotional roles of MoS2 in enhancing photo-activity of ZnCdS for photo-treatment of wastewater containing tetracycline (TC)

Ng KH 1 , Hamza M 2 , Lai SY 3 , Imanuella N 4 , Tan LS 5 , Liu CL 6 Show all authors , Wu HT 4

Affiliations 

  • 1 Department of Chemical Engineering, Ming Chi University of Technology, New Taipei, 24301, Taiwan; R&D Center of Biochemical Engineering Technology, Ming Chi University of Technology, New Taipei, Taiwan; Center for Environmental Sustainability and Human Health, Ming Chi University of Technology, New Taipei City, 24301, Taiwan; Battery Research Center of Green Energy, Ming Chi University of Technology, New Taipei, 24301, Taiwan. Electronic address: kimhoong.ng@mail.mcut.edu.tw
  • 2 Department of Chemical Engineering, Ming Chi University of Technology, New Taipei, 24301, Taiwan; R&D Center of Biochemical Engineering Technology, Ming Chi University of Technology, New Taipei, Taiwan; Center for Environmental Sustainability and Human Health, Ming Chi University of Technology, New Taipei City, 24301, Taiwan
  • 3 School of Energy and Chemical Engineering, Xiamen University Malaysia, Selangor Darul Ehsan, 43900, Malaysia
  • 4 Department of Chemical Engineering, Ming Chi University of Technology, New Taipei, 24301, Taiwan
  • 5 Malaysia - Japan International Institute of Technology, Universiti Teknologi Malaysia, Kuala Lumpur, Malaysia
  • 6 Department of Chemical Engineering, Ming Chi University of Technology, New Taipei, 24301, Taiwan; R&D Center of Biochemical Engineering Technology, Ming Chi University of Technology, New Taipei, Taiwan
Environ Res, 2025 Mar 19;275:121402.
PMID: 40118320 DOI: 10.1016/j.envres.2025.121402

Abstract

MoS2 is frequently reported as an effective photocatalytic promoter; however, its explicit roles in improving photo-activity are rarely discussed. In this regard, current study aims to unravel the promotional roles of MoS2, specifically to ZnCdS in degrading tetracycline (TC) under visible light irradiation. ZnCdS/MoS2 derived from photo-deposition approach manifested a large interface with ZnCdS-encapsulating-MoS2 architecture. Alongside MoS2-deposition, the photocatalytically-inert oxide phases of ZnCdS were concurrently eliminated, enabling better photo-responsiveness to visible light. This comes with the closure of energy gap of ZnCdS (evidenced experimentally and theoretically); however, did not weaken its reductive capability due to its unaltered conduction band position. On the other hand, though the valence band of ZnCdS would slightly elevate with MoS2-embedment, its oxidative power is still adequate for direct oxidation of TC. This, therefore, explains TC removal which predominantly assisted by photo-holes and •OH radical (produced from O2-reductive pathway). Electronically-speaking, MoS2 embedment helps in lowering the impedance of ZnCdS, facilitating charges separation while lengthening their lifetimes in photoreaction. Meanwhile, MoS2-modification could also improve TC adsorption onto ZnCdS; this helps in improving utilization of photo-charges while facilitate TC degradation. These benefitting attributes of MoS2, therefore, permitted 458% activity improvements to ZnCdS, realizing 40.93 × 10-5 ppm min-1 TC removal under visible light.

* Title and MeSH Headings from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

Similar publications