Biocompatible FeOOH-carbon quantum dots nanocomposites for gaseous NOₓ removal under visible light: Improved charge separation and high selectivity

Yu HUANG, Yunxia GAO, Qian ZHANG, Yufei ZHANG, Jun-Ji CAO, Wing Kei HO, Shun Cheng LEE

Research output: Contribution to journalArticlespeer-review

69 Citations (Scopus)

Abstract

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 NO₂ intermediates 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. Copyright © 2018 Elsevier B.V. All rights reserved.
Original languageEnglish
Pages (from-to)54-62
JournalJournal of Hazardous Materials
Volume354
Early online dateApr 2018
DOIs
Publication statusPublished - 2018

Citation

Huang, Y., Gao, Y., Zhang, Q., Zhang, Y., Cao, J.-J., Ho, W., & Lee, S. C. (2018). Biocompatible FeOOH-carbon quantum dots nanocomposites for gaseous NOₓ removal under visible light: Improved charge separation and high selectivity. Journal of Hazardous Materials, 354, 54-62. doi: 10.1016/j.jhazmat.2018.04.071

Keywords

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

Fingerprint Dive into the research topics of 'Biocompatible FeOOH-carbon quantum dots nanocomposites for gaseous NOₓ removal under visible light: Improved charge separation and high selectivity'. Together they form a unique fingerprint.