Efficient photocatalytic inactivation of E. coli by Mn-CdS/ZnCuInSe/CuInS2 quantum dots-sensitized TiO2 nanowires

Nanotechnology. 2020 Sep 25;31(39):395602. doi: 10.1088/1361-6528/ab8d6c. Epub 2020 Apr 27.

Abstract

A novel visible light-driven photocatalyst (represented as Mn-CdS/ZCISe/CIS/TiO2) for the passivation of E. coli was prepared with TiO2 nanowires as support and using CuInS2 (CIS) and ZnCuInSe (ZCISe) quantum dots (QDs), as well as Mn-doped CdS (Mn-CdS) nanoparticles (NPs) as sensitizers. The use of CIS and ZCISe QDs and Mn-CdS NPs extends the light harvest region to visible light. The photoelectric conversion efficiency was consequently improved, with a photocurrent density of 12.5 mA cm-2, about 60 times that of pure TiO2 nanowires. The germicidal efficiency of the photocatalyst was assessed by passivation of E. coli, 96% bacteria in 50 ml 105 colony forming units (CFU) ml-1 solution were killed within 50 min. Besides the high efficiency, the composite has good stability and satisfactory recycling performance. The antibiotic mechanism was also performed by using photoluminescence and a scavenging agent of different active matter, revealing that the photo-generated holes play a major role in the sterilization process.

MeSH terms

  • Anti-Bacterial Agents / chemistry
  • Anti-Bacterial Agents / pharmacology*
  • Cadmium Compounds / chemistry
  • Catalysis
  • Copper / chemistry
  • Escherichia coli / drug effects*
  • Escherichia coli / growth & development
  • Indium / chemistry
  • Manganese / chemistry
  • Microbial Viability / drug effects
  • Nanowires
  • Photochemotherapy / methods*
  • Quantum Dots
  • Selenium / chemistry
  • Sulfides / chemistry
  • Titanium / chemistry
  • Titanium / pharmacology*

Substances

  • Anti-Bacterial Agents
  • Cadmium Compounds
  • Sulfides
  • Indium
  • cadmium sulfide
  • titanium dioxide
  • Manganese
  • Copper
  • Titanium
  • Selenium