title: Fabrication highly dispersed Fe3O4 nanoparticles on carbon nanotubes and its application as a mimetic enzyme to degrade Orange II.
abstract: Fe3O4 nanoparticles were grown in situ on carbon nanotubes (CNTs) by a solvothermal method. The Fe3O4/CNTs composites were characterised by the Brunauer-Emmett-Teller method and transmission electron microscopy. The results indicated that the Fe3O4 nanoparticles were uniformly deposited on CNTs, and the average diameter was approximately 7.0 nm. The Fe3O4/CNTs were applied as an enzyme mimetic to decompose Orange II, and the decomposing conditions were optimised. At 500 mg L(-1) of Fe3O4/CNTs in the presence of 15.0 mmol L(-1) of H2O2, at 30°C, it degraded 94.0% of Orange II (0.25 mmol L(-1), pH = 3.5), showing higher catalytic activity than pure Fe3O4 nanoparticles. The high activity was attributed to the uniform Fe3O4 nanoparticles growing on the side walls of the CNTs and the synergetic effect between Fe3O4 and CNTs. The Fe3O4/CNTs maintained their activity at temperatures as high as 65°C. The Fe3O4/CNTs presented high reusability and stability even after eight uses. These data proved that the Fe3O4/CNTs-catalysed degradation is a promising technique for wastewater treatment. Fe3O4 nanoparticles were grown in situ on carbon nanotubes (CNTs) by a solvothermal method. The Fe3O4/CNTs was applied as a mimetic enzyme to decompose Orange II. The Fe3O4/CNTs were collected after the reaction by applying an external magnetic field and can use repeatedly.
authors.affiliation: a State Joint Key Laboratory of Environment Simulation and Pollution Control, Department of Environmental Engineering, School of Environment , Tsinghua University , Beijing , People's Republic of China.|b Changsha Research Institute of Mining and Metallurgy , Changsha , People's Republic of China.
authors.forename: Jingheng
authors.initials: J
authors.lastname: Deng
authors.affiliation: a State Joint Key Laboratory of Environment Simulation and Pollution Control, Department of Environmental Engineering, School of Environment , Tsinghua University , Beijing , People's Republic of China.
authors.forename: Xianghua
authors.initials: X
authors.lastname: Wen
authors.affiliation: a State Joint Key Laboratory of Environment Simulation and Pollution Control, Department of Environmental Engineering, School of Environment , Tsinghua University , Beijing , People's Republic of China.|c Development and Reform Commission of Hunan Province , Changsha , People's Republic of China.
authors.forename: Jiaxi
authors.initials: J
authors.lastname: Li
mesh_terms: D000165:Acridine Orange / Q000032:analysis / Q000737:chemistry / Q000378:metabolism*; D040761:Biomimetic Materials / Q000737:chemistry / Q000378:metabolism; D002384:Catalysis; D006863:Hydrogen-Ion Concentration; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D013696:Temperature; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000737:chemistry / Q000378:metabolism*; D018508:Water Purification / Q000379:methods*
chemical_list: D058185:Magnetite Nanoparticles; D037742:Nanotubes, Carbon; D014874:Water Pollutants, Chemical; D000165:Acridine Orange
keywords: Fe3O4/CNTs; Orange II; catalytic activity; enzyme mimetic degradation