Photocatalytic Bacterial Inactivation by a Rape Pollen-MoS2 Biohybrid Catalyst : Synergetic Effects and Inactivation Mechanisms

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review

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Author(s)

  • Kemeng Xiao
  • Tianqi Wang
  • Aamir Hanif
  • Qinfen Gu
  • Bingbing Tian
  • Zhifeng Jiang
  • Bo Wang
  • Hongli Sun
  • Po Keung Wong

Detail(s)

Original languageEnglish
Pages (from-to)537-549
Journal / PublicationEnvironmental Science and Technology
Volume54
Issue number1
Online published12 Dec 2019
Publication statusPublished - 7 Jan 2020

Abstract

A novel and efficient 3D biohybrid photocatalyst, defective MoS2 nanosheets encapsulated carbonized rape pollen, was fabricated and applied to water disinfection. The rape pollen-MoS2 (PM) biohybrid showed excellent dispersibility, high stability, and efficient charge-carrier separation and migration ability, resulting in the highly enhanced photocatalytic inactivation performance toward various waterborne bacteria under different light sources. The inactivation mechanisms were systematically investigated. Reactive species (RSs), including electrons, holes, and reactive oxygen species (- and OH), played major roles in inactivating bacteria. The antioxidant system of bacteria exhibited a self-protection capacity by eliminating the photogenerated RSs from PM biohybrid at the early stage of inactivation. With the accumulation of RSs, the cell membrane and membrane-associated functions were destroyed, as suggested by the collapse of cell envelope and subsequent loss of cell respiration and ATP synthesis capacity. The microscopic images further confirmed the destruction of the bacterial membrane. After losing the membrane barrier, the oxidation of cytoplasmic proteins and lipids caused by invaded RSs occurred readily. Finally, the leakage of DNA and RNA announced the irreversible death of bacteria. These results indicated that the bacterial inactivation began with the membrane rupture, followed by the oxidation and leakage of intracellular substances. This work not only provided a new insight into the combination of semiconductors with earth-abundant biomaterials for fabricating high-performance photocatalysts, but also revealed the underlying mechanisms of photocatalytic bacterial inactivation in depth.

Citation Format(s)

Photocatalytic Bacterial Inactivation by a Rape Pollen-MoS2 Biohybrid Catalyst : Synergetic Effects and Inactivation Mechanisms. / Xiao, Kemeng; Wang, Tianqi; Sun, Mingzhe; Hanif, Aamir; Gu, Qinfen; Tian, Bingbing; Jiang, Zhifeng; Wang, Bo; Sun, Hongli; Shang, Jin; Wong, Po Keung.

In: Environmental Science and Technology, Vol. 54, No. 1, 07.01.2020, p. 537-549.

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review