Photothermal-assisted activation of peroxymonosulfate with FeO_<i>x</i> nanoparticles anchored on carbon nitride for degradation of RhB

Abstract

Photothermal-assisted activation of peroxymonosulfate (PMS) is an effective way to promote the advanced catalytic oxidation performance. However, leaching of metal ions is a drawback for currently used metal-based catalysts, which limits their applications for water treatment. Therefore, it is important to develop high-efficient non-metal catalysts for photothermal-assisted PMS activation. Carbon nitride(CN) loaded with FeOx nanoparticles (FeOx/CN) were synthesized by the gelation-pyrolysis method. The as-prepared FeOx/CN catalysts were used to eliminate Rhodamine B (RhB) using the Fenton-like reaction by photothermal-assisted PMS activation. The crystalline structures, morphologies and light adsorption properties of the obtained nanocomposites were analyzed by using X-ray diffractometer, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, N2 adsorption-desorption and UV-vis spectrophotometer. The results show that the removal rate of RhB by CN/FeOx/PMS system can reach 98.0% under the condition of near neutral (pH=6) and photothermal(40 ℃ water bath and λ>420 nm visible-light irradiation) synergistic auxiliary reaction for 30 min. The trapping experiments demonstrate that holes (h+) and hydroxyl radicals (OH·) are major active species during the PMS activation process.

Keywords

• iron oxide
• photothermal-assisted activation
• peroxymonosulfate
• fenton-like reaction
• dye removal
• degradation