One-step synthesis of N-doped metal/biochar composite using NH3-ambiance pyrolysis for efficient degradation and mineralization of Methylene Blue


Mian M. M., Liu G., Yousaf B., Fu B., Ahmed R., Abbas Q., ...More

JOURNAL OF ENVIRONMENTAL SCIENCES, vol.78, pp.29-41, 2019 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 78
  • Publication Date: 2019
  • Doi Number: 10.1016/j.jes.2018.06.014
  • Journal Name: JOURNAL OF ENVIRONMENTAL SCIENCES
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.29-41
  • Keywords: Biochar-supported photocatalyst, N-TiO2-Fe3O4-biochar, NH3-ambiance pyrolysis, Methylene Blue, Photocatalysis, ENHANCED ADSORPTIVE REMOVAL, PHOTOCATALYTIC DEGRADATION, TIO2 NANOPARTICLES, AQUEOUS-SOLUTIONS, CARBON NANOTUBES, FACILE SYNTHESIS, BIOCHAR, HYBRID, CATALYSTS, IRON
  • Middle East Technical University Affiliated: No

Abstract

A series of new biochar-supported composite based on the combination of biochar and metallic nanoparticles (NPs) were produced through single-step pyrolysis of FeCl3-Ti(OBu)(4) laden agar biomass under NH3 environment. The physiochemical properties of composites were characterized thoroughly. It has found that heating temperature and N-doping through NH3-ambiance pyrolysis significantly influence the visible-light sensitivity and bandgap energy of composites. The catalytic activities of composites were measured by degradation of Methylene Blue (MB) in the presence or absence of H2O2 and visible-light irradiation. Our best catalyst (N-TiO2-Fe3O4-biochar) exhibits rapid and high MB removal competency (99.99%) via synergism of adsorption, photodegradation, and Fenton-like reaction. Continuous production of O-2 center dot(-) and center dot OH radicles performs MB degradation and mineralization, confirmed by scavenging experiments and degradation product analysis. The local trap state Ti3+, Fe3O4, and N-carbon of the catalyst acted as active sites. It has suggested that the Ti3+ and N-doped dense carbon layer improve charge separation and shuttle that prolonged photo-Fenton like reaction. Moreover, the catalyst is highly stable, collectible, and recyclable up to 5 cycles with high MB degradation efficiency. This work provides a new insight into the synthesis of highly visible-light sensitized biochar-supported photocatalyst through NH3-ambiance pyrolysis of NPs-laden biomass. (c) 2018 The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V.