Biocompatible FeOOH-Carbon quantum dots nanocomposites for gaseous NOxremoval under visible light: Improved charge separation and High selectivity

Yu Huang, Yunxia Gao, Qian Zhang, Yufei Zhang, Jun ji Cao, Wingkei Ho, Shuncheng Lee

Research output: Journal article publicationJournal articleAcademic researchpeer-review

87 Citations (Scopus)


Development of biocompatible photocatalysts with improved charge separation and high selectivity is essential for effective removal of air pollutants. Iron-containing catalysts have attracted extensive attention due to their low-toxicity and high natural abundance. Here, carbon quantum dots (CQDs) modified FeOOH nanocomposites fabricated using a facile hydrothermal route showed enhanced NO removal efficiency (22%) compared to pure FeOOH. Moreover, generation of toxic NO2intermediates was significantly inhibited using the nanocomposites, demonstrating high selectivity for final nitrate formation. Photo-electrochemical results showed that both charge separation and transfer efficiency were significantly improved by CQDs addition, and the lifetime of photo-generated carriers was increased eventually. Density functional theory calculations further elucidated that the suppressed recombination of photo-induced electron-hole pairs was due to enhanced electron migration from the FeOOH to CQDs. A NO degradation mechanism was proposed based on detection of the reactive oxygen species using electron paramagnetic spectroscopy. In addition, the nanocomposite showed good biocompatibility and low cytotoxity, ensuring minimal environmental impact for potential application in large-scale.
Original languageEnglish
Pages (from-to)54-62
Number of pages9
JournalJournal of Hazardous Materials
Publication statusPublished - 15 Jul 2018


  • Charge carrier separation
  • CQDs/FeOOH photocatalyst
  • Degradation mechanism
  • DFT calculation
  • NOx purification

ASJC Scopus subject areas

  • Environmental Engineering
  • Environmental Chemistry
  • Waste Management and Disposal
  • Pollution
  • Health, Toxicology and Mutagenesis

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