Graphitic carbon nitride/xylene soot metal-free nanocomposites for photocatalytic degradation of organic compounds

Abstract

Graphitic carbon nitride and soot (g-C3N4/soot) metal-free nanocomposites were synthesized by a simple one-pot thermal synthesis from mixtures of dicyandiamide with different volumes of xylene. The soot nanoparticles of 17.7 ± 1.7 nm in size were observed on the g-C3N4 surface.

The band gap energies of the synthesized nanocomposites decreased from 2.65 eV to 2.53 eV with the increasing content of soot nanoparticles. The photocatalytic activity of the g-C3N4/soot nanocomposites to degrade phenol, ofloxacin, and ampicillin under the LED irradiation of 420 nm was investigated. Time-resolved photoluminescence measurements, electrochemical impedance spectroscopy, and trapping experiments indicated that photoinduced electrons were accumulated in the soot particles, reacted with oxygen forming superoxide radicals, which decomposed the organic compounds. The degradation efficiency decreased in the sequence ofloxacin > ampicillin > phenol. The g-C3N4/soot nanocomposites were investigated for the photocatalytic degradation of organic compounds for the first time.